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Ultimate Guide for Cine EI on the Sony PXW-FS7

advertise-here-275 Ultimate Guide for Cine EI on the Sony PXW-FS7

Ultimate Guide to CineEI on the PXW-FS7 (Updated May 2016).

 

INTRODUCTION:

This guide to Cine-EI is based on my own experience with the Sony PXW-FS7. There are other methods of using LUT’s and CineEI. The method I describe below, to the best of my knowledge, follows standard industry practice for working with a camera that uses EI gain and LUT’s.

If you find the guide useful, please consider buying me a beer or a coffee. It took quite a while to prepare this guide and writing can be thirsty work.


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Through this guide I hope to help you get the very best from the Cine EI mode on the PXW-FS7.

The camera has two very distinct shooting mode, Cine EI and Custom Mode. In custom mode the camera behaves much like any other traditional video camera where what you see in the viewfinder is what’s recorded on the cards. In custom mode you can change many of the cameras settings such as gamma, matrix, sharpness etc to create the look you are after in-camera. “Baking-in” the look of your image in camera is great for content that will go direct to air or for fast turn around productions. But a baked-in look can be difficult to alter in post production. In addition it is very hard to squeeze every last drop of the picture information that the sensor can capture in to the recordings in this mode.

The other mode, Cine-EI, is primarily designed to allow you to record as much information about the scene as possible. The footage from the camera becoming, in effect a “digital negative” that can then be developed in post production and the final, highly polished look of the film or video created in post. In addition the Cine-EI mode mimics the way a film camera works giving the cinematographer the ability to rate the camera at different ISO’s to those specified by Sony. This can be used to alter the relative noise levels in the footage or to help deal with difficult lighting situations.

One further “non-standard” way to use Cine-EI is to use a LUT (Look Up Table) to create an in-camera look that can be baked in to the footage while you shoot. This offers an alternative to custom mode. Some users will find it easier to create a specific look for the camera using a LUT than they would by adjusting camera settings such as gamma and matrix.

MLUT’s and LOOK’s (both are types of Look Up Tables) are only available in the Cine-EI mode.


 

THE SIMPLIFIED VERSION:

Before I go through all the “why’” and “hows” first of all let me just say that actually, CineEI is easy. I’ve gone in to a lot of extra detail here so that you can fully master the mode and the concepts behind it.

But in it’s simplest form, all you need to do is to turn on the MLUT’s. Choose the MLUT that you like the look of, or is closest to the final look you are after. Expose so that the picture in the viewfinder or on your monitor looks how you want and away you go.

Then in post production bring in your S-log footage. Apply the same LUT as you used when you shot and the footage will look as shot. Or just grade the footage as desired without a LUT, it is not essential to use a LUT in post production.  As the footage you have shot is either raw or Slog you have a huge range of adjustment available to you in post.

THAT’S IT! If you want, it’s that simple (well almost).

If you want to get fancy you can create your own LUT and that’s really easy too (see the end of the document). If you want less noise in your pictures use a lower EI. I shoot using 800EI on my FS7 almost all the time.

Got an issue with a very bright scene and strong highlights, shoot with a high EI (this should only ever be a last resort, try to avoid using an EI higher than 2000EI).

Again, it’s really simple.

But anyway, lets learn more about it and why it works the way it works.

LATITUDE AND SENSITIVITY.

The latitude and sensitivity of the PXW-FS7, like most cameras is primarily governed by the latitude and sensitivity of the sensor. The latitude of the sensor in the FS7 is around 14 stops. Adding different amounts of conventional camera gain or using  different ISO’s does not alter the sensors actual sensitivity to light, only how much the signal from the sensor is amplified. This is like turning up or down the volume on a radio, the sound level gets higher or lower, but the strength of the radio signal is just the same. Turn it up loud and not only does the music get louder but also any hiss or noise, the ratio of signal to noise does not change, so BOTH the noise and the music get louder. Turn it up too loud and it will distort. If you don’t turn it up loud enough, you can’t hear it, but the radio signal itself does not change. It’s the same with a video cameras sensor. It always has the same sensitivity, With a conventional camera, or when the FS7 is in Custom Mode we can add or take away gain (volume control?) to make the pictures brighter or darker (louder?) but the noise levels will go up and down too.

NATIVE ISO:

Sony’s native ISO rating for the FS7 of 2000 ISO has been chosen by Sony to give a good trade off between sensitivity, noise and over/under exposure latitude. In general the native ISO will give excellent results. But there may be situations where you want or need different performance. For example you might prefer to trade off a little bit of over exposure headroom for a better signal to noise ratio, giving a cleaner, lower noise picture. Or you might need a very large amount of over exposure headroom to deal with a scene with lots of bright highlights.

The Cine EI mode allows you to change the effective ISO rating of the camera, without altering the dynamic range.

With film stocks the film manufacturer will determine the sensitivity of the film and give it an Exposure Index which is normally the equivalent of the films measured ASA/ISO.  It is possible for a skilled cinematographer to rate the film stock with a higher or lower ISO than the manufacturers rating to vary the look or compensate for filters and other factors. You then adjust the film developing and processing to give a correctly exposed looking image. This is a common tool used by cinematographers to modify the look of the film, but the film stock itself does not actually change it’s base sensitivity, it’s still the same film stock with the same base ASA/ISO.

Sony’s Cine EI mode and the EI modes on Red and Arri cameras are very similar. While it has many similarities to adding conventional video camera gain, the outcome and effect can be quite different. If you have not used it before it can be a little confusing, but once you understand the way it works it is very useful and a great way to shoot. Again, a key thing to remember that the actual sensitivity of the sensor itself never changes.


CONVENTIONAL VIDEO CAMERA GAIN.

Increasing conventional camera gain will reduce the cameras dynamic range as something that is recorded at maximum brightness (109%) at the native ISO or 0db would be pushed up above the peak recording level and we can’t record a signal larger than 109%. But as the true sensitivity of the sensor does not change, the darkest object the camera can actually detect remains the same. Dark objects may appear a bit brighter, but there is still a limit to how dark an object the camera can actually see and this is governed by the sensors noise floor and signal to noise ratio (how much noise there is in the image coming from the sensor).

Any very dark picture information will be hidden in the sensors noise. Adding gain will bring up both the noise and darkest picture information, so anything hidden in the noise at the native ISO (or 0db) will still be hidden in the noise at a higher gain or ISO as both the noise and small signal are amplified by the same amount. So adding gain does not extend the the ability to see further into the shadows, but does decrease the ability to record bright highlights. The net result of adding gain is a decrease in dynamic range.

Using negative gain or going lower than the native ISO may also reduce the dynamic range as picture information very close to black will be shifted down below black when you subtract gain or lower the ISO. At the same time there is a limit to how much light the sensor can deal with before the sensor itself overloads. So even though reducing the ISO or gain may make the picture darker, the sensors clipping/overload point remains the same, so there is no change to the upper dynamic range, just a reduction in recording level. The net result is you loose shadow information, don’t gain any highlight information, this again means a reduction in dynamic range.

See also this article on gain and dynamic range.

As Sony’s Slog2 and Slog3 are tailored to capture the cameras full 14 stop range this means that when shooting with Slog2 or Slog3 the gamma curve will ONLY work as designed and deliver the maximum dynamic range when the camera is at it’s native ISO. At any other recording ISO or gain level the dynamic range will be reduced. IE: If you were to use SLog2 or SLog3 with the camera in custom mode and not use the native ISO by adding gain or changing the ISO away from 2000, you will not get the full 14 stop range that the camera is capable of delivering.

 

EXPOSURE LEVELS FOR DIFFERENT GAMMA CURVES AND CONTRAST RANGES.

It’s important to understand that different gamma curves with different contrast ranges will require different exposure levels. The TV system that we use today is currently based around a standard known as Rec-709. This standard specifies the contrast range that a TV set or monitor can show and which recording levels represent which display brightness levels. Most traditional TV cameras are also based on this standard. Rec-709 does have some serious restrictions, the brightness and contrast range is very limited as these standards are based around TV standards and technologies developed 50 years ago. To get around this issue most TV cameras use methods such as a “knee” to compress together some of the brighter part of the scene in to a very small recording range.

A traditional TV camera with a limited dynamic range compresses only a small highlight range.

 

Slide2 Ultimate Guide for Cine EI on the Sony PXW-FS7
A traditional TV camera with a limited dynamic range compresses only a small highlight range.

As you can see in the illustration above only a very small part of the recording “bucket” is used to hold a moderately large compressed highlight range. In addition a typical TV camera can’t capture all of the range in many scenes anyway. The most important parts of the scene, from black to white, is captured more or less “as is”. This leaves just a tiny bit of space above white to squeeze in a few highly compressed highlights. The black to white range represents about 5 stops, these are the most important stops as the majority of things that are important fall in this range. Faces, skin tones, plants, buildings etc all fall within the black to white range. Anything brighter than white must be a direct light source such as the sky, a reflection or lamp.

The signal from the TV camera is then passed directly to the TV and as the shadows, mid range and skin tones etc are all at more or less the same level as captured the bulk of scene looks OK on the TV/Monitor. Any highlights or other brighter than white direct light sources may look a little “electronic” due to the very large amount of compression used.

But what happens if we want to record more of the scenes range or compress the highlights less? As the size of the recording “bucket”, the codec etc, does not change, in order to capture a greater range and fit it in to the same space, we have to re-distribute how we record things.

Recording a greater dynamic range into the same sized bucket.

Slide3 Ultimate Guide for Cine EI on the Sony PXW-FS7
Recording a greater dynamic range into the same sized bucket.

Above you can see instead of just compressing a small part of the highlights we are now capturing the full dynamic range of the scene. To do this we have altered the levels that everything is recorded at. Blacks and shadows are recorded lower, greys and mids are lower and white is a lot lower. By bringing all these levels down, we make room in our recording bucket for the highlights and the really bright stuff without them being excessively compressed.

The problem with this though is that when you output the picture to a monitor or TV it looks odd. It will lack contrast as the really bright stuff is displayed at the same brightness as the conventional 709 highlights. White is now darker then faces would be with a conventional TV camera.

This is how S-Log works:

This is how Slog works. By re-distributing the recording levels we can squeeze a much bigger dynamic range into the same size recording bucket. But it won’t look right when viewed directly on a standard TV or monitor. It may look dark and certainly a bit washed out. This is because the cameras gamma curve now no longer matches the monitors gamma curve.

I hope you can also see from this that whenever the cameras gamma curve does not match that of the TV/Monitor, the picture might not look quite right. Even when correctly exposed, white may be at different levels, depending on the gamma being used, especially if the gamma curve has a greater range than the normal Rec-709 used in old school TV cameras.

 


 

THE CORRECT EXPOSURE LEVELS FOR SLOG-2 and SLOG-3.

Before we go any further lets just look at the correct exposure levels for SLog-2 and SLog-3 as recommended by Sony. As these gamma curves have a very large dynamic range the recording levels that they use are very different to the levels used by the normal 709 gamma curve used for conventional TV. As a result when correctly exposed, Slog looks dark and low contrast on a conventional monitor or in the viewfinder. The table below has the correct levels for middle grey (grey card) and 90% reflectance white (a white card) for the different types of Slog.

log-exposure-1024x190 Ultimate Guide for Cine EI on the Sony PXW-FS7
Correct exposure levels for Sony’s Slog.

Correct exposure levels for Sony’s Slog.

The white level in particular is a lot lower than we would normally use for TV gamma. This is done to give extra space above white to fit in the extended range that the camera is capable of capturing, all those bright highlights, bright sky and clouds and other things that cameras with a smaller dynamic range struggle to capture.

SETTING THE CORRECT EXPOSURE.

Let’s now take a look at how to set the correct starting point exposure for SLog-3. You can use a light meter if you wish, but if you do want to use a light meter I would first suggest you check the calibration of the light meter by using the grey card method below and comparing what the light meter tells you with the results you get with a grey or white card.

The most accurate method is to use a good quality grey card and a waveform display. For the screen shots seen here I used a Lastolite EzyBalance Calibration Card. This is a pop up grey card/white card that fits in a pocket but expands to about 30cm/1ft across giving a decent sized target. It has middle grey on one side and 90% reflectance white on the other. With the MLUT’s off, set the exposure so that the grey card is exposed at the appropriate level (see table above). If the firmware in your camera is up to date (at least version 3.0) you can set the zebras to 32% or 41% to do this or use an external monitor with a waveform display. The FS7’s built in waveform display is very had to use as it is so small and has no scale. I also recommend the use of a DSC Labs “One Shot” chart. The front of the chart has a series of color references that can be used in post production to set up your base color correction while the rear of the chart has both a large middle grey and 90% white square.

 

USING THE FS7’s WAVEFORM MONITOR OR ZEBRAS TO SET THE CORRECT BASE S-LOG3 EXPOSURE.

IMPORTANT NOTE: If you use a LUT, The Zebras measure the viewfinder image, so if a LUT is on for the the viewfinder, then the zebras measure the LUT. If there is no viewfinder LUT then the zebras measure the S-Log.

The Waveform Monitor and Histogram measure the SDI2 levels. So if you have a LUT on for SDI2 then the LUT levels are measured. If there is no LUT on SDI2 then the S-Log levels are measured.

See this video for more information on the Waveform, Histogram and Zebras:

The internal waveform display settings are found in the menu under:

VF: Display On/Off: Video Signal Monitor.

LUT-middlegrey41 Ultimate Guide for Cine EI on the Sony PXW-FS7
Setting the correct exposure for Slog-3 using a grey card. Middle grey should be 41%

Setting the correct exposure for Slog-3 using a grey card. Middle Grey should be 41%

If you don’t have access to a better waveform display you can use a white card or grey card and zebras. When using zebras I prefer to use white as the reference as it is easier to see the zebras on a white target than a grey one. By setting up the Zebras with a narrow aperture window of around 3% you can get a very accurate exposure assessment for white. For SLog-3 set the Zebras to 3% aperture and the level at 61%.  For Slog-2 set the zebra level to 59%. To be honest, if you were to set the zebras to 60% this is going to work for both S-Log2 and S-Log3, a 1% error is too small to make any difference and variations in lighting or the white target will be greater than 1% anyway.

Setting up the Zebras to measure S-Log3 exposure of white card (90% reflectance white card).

zebras61 Ultimate Guide for Cine EI on the Sony PXW-FS7
Setting up the Zebras to measure S-Log3 exposure of white card (90% reflectance white card).

Correct exposure for S-Log3 when using a 90% reflectance white target.

LUT-white61 Ultimate Guide for Cine EI on the Sony PXW-FS7
Correct exposure for S-Log3 when using a 90% reflectance white target.

The image above shows the use of both the Zebras and Waveform to establish the correct exposure level for S-Log3 when using a 90% reflectance white card or similar target. Please note that very often a piece of white paper or a white card etc will be a little bit brighter than a calibrated 90% white card. If using typical bleached white printer paper I suggest you add around 4% to the white values in the above chart to prevent under exposure.

This will get you to the base exposure recommended by Sony, without using a LUT. But very often we want to expose brighter than this to improve the signal to noise ratio.

See also the video below for information on how to setup and use S-Log2 and S-Log3 in the CineEI mode:

 

USING LUTS’s and CINE EI:

SO HOW DOES CINE-EI WORK?

FS7-CineEI-seletion-page-1024x576 Ultimate Guide for Cine EI on the Sony PXW-FS7
Selecting Cine EI in base settings on the PXW-FS7

Cine EI is selected in the Base Settings page. It works in YPbPr, RGB and Raw main operation modes.

Cine-EI (Exposure Index) works differently to conventional camera gain. It’s operation is similar in other cameras that use Cine-EI or EI gain such as the F5, F55, F3, F65, Red or Alexa. You enable Cine-EI mode in the camera menus Base Settings page. On the F5 and F55 it works in YPbPr, RGB and RAW modes.

IMPORTANT: In the Cine-EI mode the ISO of the recordings remains fixed at the cameras native ISO (unless baking in a LUT,  more on that later). By always recording at the cameras native ISO you will always have 14 stops of dynamic range.

YOU NEED TO USE A LUT FOR CINE EI TO WORK:

You can only use LUT’s in the CineEI mode. In addition in order to be able to have LUT’s on for the Viewfinder, HDMI / SDI2, but NOT on the SD1 & Internal Rec you cannot set the HDMI to output 4K, you can only use HD or 2K.

FS7-Output-Settings-1024x576 Ultimate Guide for Cine EI on the Sony PXW-FS7
PXW-FS7 output options.

So for most applications you will want to set your SDI and HDMI outputs to HD/2K in order to ba able to use the LUT system as designed for CineEI. For reference (2-3PD) means 2-3 pull down is added for 24p footage, so the output will be 60i with 24p footage sgown using pull down. PsF means progressive segmented frame which is the normal HDSDI standard for progressive output. Any of the HD or 2K output modes will allow the use of LUT’

 

Important: For Cine-EI mode to work as expected you MUST monitor your pictures in the viewfinder or via the SDI/HDMI output through one of the cameras built in MLUT’s (Look Up Table), LOOK’s or User3D LUT’s. So make sure you have the MLUT’s turned on. If you don’t have a LUT then it won’t work as expected because the EI gain is applied to the cameras LUT’s.

At this stage just set the MLUT’s to on for the Sub&HDMI output and the Viewfinder out.

 

FS7-LUT-settings-1024x576 Ultimate Guide for Cine EI on the Sony PXW-FS7
PXW-FS7 Lut selection settings.

The LUT’s are then turned on in the VIDEO: Monitor LUT: settings page of the menu. You will normally want to turn ON LUT’s for SDI2, HDMI and the VIEWFINDER (not seen in the image above, simply scroll down to the bottom of the page to see the VIEWFINDER option). For normal CinEI use you should leave SD1 & Internal Rec OFF as we don’t want to record the LUT, just monitor via the LUT.

EXPOSING VIA THE LUT/LOOK.

When viewing or monitoring via a LUT you should adjust your exposure so that the picture in the viewfinder looks correctly exposed. If the LUT is correctly exposed then The S-Log recording will also be correctly exposed. As a point of reference, middle grey for Rec-709 and the 709(800) LUT should be at, or close to 44% and white will be 90%. Skin tones and faces will be at the normal TV level of around 65-70%. As these levels are waht we are used to seeing with a conventional video camera, this makes judging exposure easy.

This is really quite simple, generally speaking when using a Rec709  LUT, if it looks right in the viewfinder, it probably is right. However it is important to note that different LUT’s will have slightly different optimum exposure levels. For example the 709(800) LUT is designed to be a very close match to the 709 gamma curve used in the majority of monitors, so this particular LUT is really simple to use because if the picture looks normal on the monitor then your exposure will also be normal. The included 709(800) LUT is the most accurate LUT for exposure as this matches the gamma used in the majority of monitors. This LUT produces a nice contrasty image that is easy to focus. It is not meant to be pretty! It is a tool to help you get accurate exposure simply and easily.

Correct exposure of Middle Grey for the 709(800) MLUT. Middle Grey should be 44%. 90% white (a white piece of paper) will be 90% and skin tones will be around 65-70%.

Correct exposure of the 709(800) LUT using a 90% white card, white will be 90%. You can use zebras at 90% to check this level (remember zebras etc measure the LUT exposure level when LUT’s are turned on).

LUT-middlegrey42 Ultimate Guide for Cine EI on the Sony PXW-FS7
Correct exposure of Middle Grey for the 709(800) MLUT. Middle Grey should be 42%. 90% will be 90%.
LUT-white90 Ultimate Guide for Cine EI on the Sony PXW-FS7
Correct exposure of the 709(800) LUT using a 90% white card, white will be 90%. You can use zebras at 90% to check this level.

The above images show the correct exposure levels for the 709(800) LUT. Middle grey should be 44% and 90% white is… well 90%. Very simple and you can easily use zebras to check the white level by setting them to 90%. As middle grey is where it normally is on a TV or monitor and white is also where you would expect to see it, when using the 709(800) LUT, if the picture looks right in the viewfinder then it generally is right. This means that the 709(800) LUT is particularly well suited to being used to set exposure as a correctly exposed scene will look “normal” on a 709 TV or monitor. SIMPLE!

I don’t recommend the use of any of the other LUT’s to set exposure because all of the other LUT’s have brightness ranges that are different to Rec-709. As a result the LUT has to be exposed at non standard levels to ensure the S-Log is exposed correctly. You can use any of the other LUT’s or LOOK if you really wish, but you will need to figure out the correct exposure levels for each LUT.

The LC709-TypeA Look is very popular as a LUT for the FS7 as it closely mimics the images you get from an Arri Alexa (“type A” = type Arri).

The “LC” part of the Look’s name means Low Contrast and this also means – big dynamic range. Whenever you take a big dynamic range (lots of shades) and show it on a display with a limited dynamic range (limited shades) all the shades in the image get squeezed together to fit into the monitors limited range and as a result the contrast gets reduced. This also means that middle grey and white are also squeezed closer together. With conventional 709 middle grey would be 42% and white around 80-90%, but with a high dynamic range/low Contrast gamma curve white gets squeezed closer to grey to make room for the extra dynamic range. This means that middle grey will remain close to 42% but white reduces to around 72%. So for the LC709 Looks in the FS7 optimum exposure is to have middle grey at 42% and white at 72%. Don’t worry too much if you don’t hit those exact numbers, a little bit either way does little harm.

Correct white level for the LC709 LOOK’s. White should be around 72%

LUT-white72 Ultimate Guide for Cine EI on the Sony PXW-FS7
Correct white level for the LC709 LOOK’s. White should be around 72%

 

Top Tip: Not sure how many people are aware of this function and how it works, but it’s a great way to get around the inability to easily turn the LUT’s on and off in the CineEI mode.

Assign the Hi/Low Key option to one of your assignable buttons. So when using the 709(800) LUT (or any other LUT for that matter) the first press of the button darkens the VF image so you can see what highlights beyond the range of the LUT are doing exposure wise. This allows you to check for clipping that may be present in the much wider range S-log recordings. Press it again and you will see the image brighten allowing you to see further into the shadows so you can see the darkest things being captured by the S-log recordings. The Hi/Low Key function is a great way of seeing your full available exposure range without needing to turn the LUT on and off.

LUT EXPOSURE LEVELS FOR THE OTHER LUTS.

Here are some white levels for some of the built in LUT’s. The G40 or G33 part of the HG LUT’s is the recommended value for middle grey. Use these levels for the zebras if you want to check the correct exposure of a 90% reflectance white card. I have also include an approximate zebra value for a piece of typical white printer paper.

709(800) = Middle Grey 42%. 90% Reflectance white 90%, white paper 92%.

HG8009(G40) = Middle Grey 40%. 90% Reflectance white 83%, white paper 86%.

HG8009(G33) = Middle Grey 33%. 90% Reflectance white 75%, white paper 80%.

The “LC709” LOOK’s = Middle Grey 42%. 90% Reflectance white 72%, white paper 77%.

DONT PANIC if you don’t get these precise levels! I’m giving them to you here so you have a good starting point. A little bit either way will not hurt. Again, generally speaking if it looks right in the viewfinder or on your monitor screen, it is probably close enough not to worry about it.

BUT, again I would suggest sticking to the 709(800) LUT for setting exposure. It’s not the prettiest LUT, but is the only one of the included LUT’s that gives the correct, normal, brightness and contrast range on a conventional monitor, viewfinder or TV. If you want to keep things simple and accurate use 709(800).

USING EI OR EXPOSURE INDEX.

What is EI? EI stands for Exposure Index. This is NOT the same thing as ISO.

ISO is the sensitivity of the camera. ISO is the sensitivity that the camera records at.

EI is the sensitivity of the LUT. EI is the brightness at which the LUT displays the scene.

The FS7 has a native ISO of 2000 and the camera always records at 2000 ISO in the Cine EI mode.

But the EI of the LUT can be varied to make the LUT brighter and darker. the only thing EI changes is the brightness of the LUT. But when exposing via the LUT, if the LUT is made darker, to compensate for the dark looking LUT you open the aperture to let in more light. This will make the LUT look correct again. It will also result in a recording that is brighter than normal as we have opened the aperture.

CHANGING THE EI.

Latitude Indication.

At the native 2000 EI you have 6 stops of over exposure latitude and 8 stops of under exposure latitude (6 stops above middle grey and 8 stops below middle grey). This is how much headroom your shot has. Your over exposure latitude is indicated whenever you change the EI level. In the image below you can see the EI 2000EI followed by a 6.0E the 6.0E is the over exposure latitude.

FS7-EI-indication-2-1024x576 Ultimate Guide for Cine EI on the Sony PXW-FS7
The EI and Lattitude indication on the FS7.

The EI gain is altered by changing the cameras gain switch and the EI levels assigned to each of the Hi/Mid/Low switch positions can be changed in the camera menu. I recommend setting the EI steps to H 2000, M 1000 and L 500 as this allows you to select the native EI plus 1 stop and 2 stops down (each time you halve the ISO you are shifting the exposure one stop down).

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The PXW-FS7 EI settings for the gain switch.

REDUCING THE EI.

So what happens when you halve the EI gain to 1000EI?  1 stop of gain/ISO will subtracted from the LUT. As a result the picture you see via the LUT becomes one stop darker (a good thing to know is that 1 stop of exposure is the same as 6db of gain or a doubling or halving of the ISO). So the picture in the viewfinder gets darker. But also remember that the camera will still be recording at the native ISO (unless baking-in the LUT).


 

Why does this happen and what’s happening to my pictures?

First of all lets take a look at the scene, as seen in the cameras viewfinder when we are at the native 2000 EI and then with the EI changed one stop down so it becomes 1000EI. The native ISO on the left, the one stop lower EI on the right.

VF-side-by-side Ultimate Guide for Cine EI on the Sony PXW-FS7
2000EI and 1000EI as seen in the viewfinder with NO exposure change.

2000EI and 1000EI as seen in the viewfinder with NO exposure change.

So, in the viewfinder, when you lower the EI by one stop (halving the EI) the picture becomes darker by 1 stop. If using an external monitor with a waveform display connected to SDI2 or the HDMI output this too would get darker and the waveform levels decrease by one stop.

As a camera operator, what do you do when you have a dark picture? Well most people would normally compensate for a dark looking image by opening the iris to compensate. As we have gone one stop darker with the EI gain, making the LUT 1 stop darker, to return the viewfinder image back to the same brightness as it was at the native EI you would open the iris by one stop.

So now, after reducing the EI by one stop and then compensating by opening the iris by 1 stop, the viewfinder image is the same brightness as it was when we started.

But what’s happening to my recordings?

Remember the recordings, whether on the XQD card (assuming the SD1 & Internal Rec LUT is OFF) are always at the cameras native 2000 ISO, no matter what the EI is set to. As a result, because you will have opened the iris by 1 stop to compensate for the dark viewfinder image the recording will have become 1 stop brighter. Look at the image below to see what we see in the viewfinder alongside what is actually being recorded. The EI offset exposure with aperture correction as seen in the viewfinder (left hand side) looks normal, while the actual native ISO recording (right hand side) is 1 stop brighter.

At 1000EI the Viewfinder image on the left is 1 stop darker than the actual recorded image (on the right) which is recorded at the native 2000 ISO.

VF-and-Internal Ultimate Guide for Cine EI on the Sony PXW-FS7

How does this help us, what are the benefits?

When you take this brighter recorded image in to post production the colorist will have to bring the levels back down to normal as part of the grading process. As he/she will be reducing the levels in post production by around 1 stop (6db) any noise in the picture will also be reduced by 6db. The end result is a picture with 6db less noise than if shot at the native EI. Another benefit may be that as the scene was exposed brighter you will be able to see more shadow information.

Is there a down side to using a low EI?

Because the actual recorded exposure is brighter by one stop you have one stop less headroom. However the PXW-FS7 has an abundance of headroom so the loss of one stop is often not going to cause a problem. I find that going between 1 and 1.5 EI stops down rarely results in any highlight issues. But when shooting very high contrast scenes and using a low EI it is worth toggling the LUT on and off to check for clipping in the SLog image.

It’s also worth noting the S-Log does not have a highlight roll off. Each stop above middle grey is recorded with the same amount of data, so exposing brighter by a stop or two does not alter the contrast as it would with a standard gamma. So over exposing log is NOT a bad thing. It is in fact in most cases highly beneficial.

Log gamma curves have very little picture information in the shadows, so if we can expose brighter our shadows will look much better. 

What is happening to my exposure range?

What you are doing is moving the mid point of your exposure range up in the case of a lower EI (up because you are opening the aperture, thus making the recordings brighter). This allows the camera to see deeper into the shadows increasing the under exposure latitude, but reduces the over exposure latitude. The reverse is also possible. If you use a higher EI you shift your mid point down. This gives you more headroom for dealing with very bright highlights, but you won’t see as far into the shadows and the final pictures will be a little noisier as in post production the overall levels will have to be brought up to compensate for the darker overall recordings.

Cine-EI allows us to shift our exposure mid point up and down.  Lowering the EI gain gives you a darker VF image so you compensate by opening the aperture which results in brightly exposed footage. This reduces over exposure headroom but increases under exposure range (and improves the signal to noise ratio). Adding EI gain gives a brighter Viewfinder image which makes you expose the recordings darker, which gives you more headroom but with less underexposure range (and a worse signal to noise ratio).

When shooting with almost any CineEI camera I will use an EI that is between 1 and 2 stops darker than the base settings. So on the FS7 I normally set the EI to 800 EI. It’s very rare to get any highlight problems at 800 EI and the improvement this low EI brings to the noise levels in the image is very nice.

Slide01 Ultimate Guide for Cine EI on the Sony PXW-FS7

Post Production.

When shooting raw information about the EI gain is stored in the clips metadata. The idea is that this metadata can be used by the grading or editing software to adjust the clips exposure level in the edit or grading application so that it looks correctly exposed (or at least exposed as you saw it in the viewfinder via the LUT). The metadata information is recorded alongside the XAVC footage when shooting SLog2/3. However, currently few edit applications or grading applications use this metadata to offset the exposure, so S-Log2/3 material may look dark/bright when imported into your edit application and you may need to add a correction to return the exposure to a “normal” level. You can use a correction LUT to move the exposure up and when I provide LUT sets on this website I will always try to include LUT’s for over and under exposure. Another way to deal with brightly exposed log footage in post production is to first apply an “S” curve using the luma curve tool to the log. Then a simple gain adjustment will shift the exposure.

See this video for detailed information on how to expose using CineEI:

 


 WHAT IF YOU ARE SHOOTING USING HFR (High Frame Rate) AND LUT’S CANT BE USED.

In HFR you can either have LUT’s on for everything including internal recording, or all off, no LUT’s at all. This is not helpful if your primary recordings are internal S-Log.

So for HFR in many cases you will have to just work viewing the native S-log. If you set zebras to 70% and expose a white card at 70% this will result in S-Log footage that is 1.2 – 1.5 stops over exposed. This is the same as shooting at 800 EI and I highly recomend this approach for HFR (slow motion) shooting as it will help clean up the additional noise that you see when shooting HFR.

 

BAKING IN THE LUT/LOOK.

When shooting using a high or low EI, the EI gain is added or subtracted from the LUT or LOOK, this makes the picture in the viewfinder or monitor fed via the LUT brighter or darker depending on the EI used. In Cine-EI mode you want the camera to always actually record the S-log at the cameras native 2000 ISO. So normally you want to leave the LUT’s OFF for the internal recording. Just in case you missed that very important point: normally you want to leave the LUT’s OFF for the internal recording!

FS7-Lut-settings-2-1024x576 Ultimate Guide for Cine EI on the Sony PXW-FS7
You need to turn ON the SD1 and Internal Rec LUT t “Bake In” a LUT. Normally leave this OFF.

Just about the only exceptions to this might be when shooting raw or when you want to deliberately record with the LUT/Look baked in to your XQD recordings. By “baked-in” I mean with the gamma, contrast and color of the LUT/Look permanently recorded as part of the recording. You can’t remove this LUT/look later if it’s “baked-in”.

No matter what the LUT/Look settings, if you’re recording raw on an external raw recorder, recorder the raw is always recorded at 2000 ISO.  But the internal XQD recordings are different. It is possible, if you choose, to apply a LUT/LOOK to the XQD recordings by setting the “SDI1 & Internal Rec” LUT to ON. The gain of the recorded LUT/LOOK will be altered according to the CineEI gain settings. This might be useful to provide an easy to work with proxy file for editing, with the LUT/LOOK baked-in while shooting raw. Or as a way to create an in-camera look or style for material that won’t be graded. Using a baked-in LUT/LOOK for a production that won’t be graded or only have minimal grading is an interesting alternative to using Custom Mode that should be considered for fast turn-around productions.

In most cases however you will probably not have a LUT applied to your primary recordings. If shooting in S-Log you must set LUT – OFF for “SDI1 & Internal Rec” See the image above. With “SDI1 & Internal Rec” Off the internal recordings, without LUT, will be SLog2 or Slog3 and at 2000 ISO.

You can tell what it is that the camera is actually recording by looking in the viewfinder. At the center right side of the display there is an indication of what is being recorded on the cards. Normally for Cine-EI this should say either SLog2 or Slog3. If it indicates something else, then you are baking the LUT in to the internal recordings.

LUT-Slog3-indication Ultimate Guide for Cine EI on the Sony PXW-FS7
The internal recording gamma is shown on the right of the VF. This is recording SLog-3
LUT-LUT709-indication Ultimate Guide for Cine EI on the Sony PXW-FS7
The indication here shows that the 709(800) LUT is being baked-in to the internal recordings.

CINE-EI SUMMARY:

CineEI allows you to “rate” the camera at different ISO.

You MUST use a LUT for CineEI to work as designed.

A low EI number will result in a brighter exposure which will improve the signal to noise ratio giving a cleaner picture or allow you to see more shadow detail. However you will loose some over exposure headroom.

A high EI number will result in a darker exposure which will improve the over exposure headroom but decrease the under exposure range. The signal to noise ratio is worse so the final picture may end up with more noise.

A 1D LUT will not clip and appear to overexpose as readily as a 3D LOOK when using a low EI, so a 1D LUT may be preferable.

When viewing via a 709 LUT you expose using normal 709 exposure levels. Basically if it looks right in the viewfinder or on the monitor (via the 709 LUT) it almost certainly is right.

When I shoot with my FS7 I normally rate the camera at between 800 and 1000EI. I find that 5 stops of over exposure range is plenty for most situations and I prefer the decrease in noise in the final pictures. But please, test and experiment for yourself.


 

QUICK GUIDE TO CREATING YOUR OWN LOOK’s (Using DaVinci Resolve).

It’s very easy to create your own 3D LUT for the FS7 using DaVinci Resolve or just about any grading software with LUT export capability. The LUT should be a 17x17x17 or 33x33x33 .cube LUT. This is what Resolve creates by default and .cube LUT’s are the most common types of LUT in use today.

First simply shoot some test Slog3 clips at 2000EI. In addition you should also use the same color space (S.Gamut or S.Gamut3.cine) for the test shot as you will when you want to use the LUT. I recommend shooting a variety of clips so that you can asses how the LUT will work in different lighting situations.

Import and grade the clips from the test shoot in Resolve creating the look that you are after for your production or as you wish your footage to appear in the viewfinder of the camera. Then once your happy with the look of the graded clip, right click on the clip in the timeline and “Export LUT”. Resolve will then create and save a .cube LUT.

Then place the .cube LUT file created by the grading software on an SD card in the PMWF55_F5 folder. You may need to create the following folder structure on the SD card. So first you have a PRIVATE folder, in that there is a SONY folder and so on.

PRIVATE   :   SONY   :    PRO   :   CAMERA   :    PMWF55_F5

Put the SD card in the camera, then go to the “File” menu and go to “Monitor 3D LUT” and select “Load SD Card”. The camera will offer you a 1 to 4 destination memory selection. Choose 1,2,3 or 4, this is the memory location where the LUT will be saved. You should then be presented with a list of all the LUT’s on the SD card. Select your chosen LUT to save it from the SD card to the camera.

Once loaded in to the camera when you choose 3D User LUT’s you can select between user LUT memory 1,2,3 or 4. Your LUT will be in the memory you selected when you copied the LUT from the SD card to the camera.

 

90 thoughts on “Ultimate Guide for Cine EI on the Sony PXW-FS7”

  1. Do you shoot Cine EI for all work? For example, if you were doing run and gun shooting, moving indoors (with only available light) to outdoors- would you shoot in a Custom profile to allow for proper exposure in the viewfinder or continue to shoot in Cine EI and then push the “negative” in post? (And I’m referring only to the XQD recordings not RAW)

  2. Mr. Chapman,

    What a terrific article! Anyone buying an FS7 would be well served reading it. Thank you for your efforts.

    Bob

  3. Great article thanks. Just for my clarification, you can set correct exposure levels for S-Log3 EITHER with grey or white levels, right? OR, you can set exposure levels using an 709 LUT at proper white or grey levels. Any of the above options work, right? You don’t need to check both?
    Thanks

  4. Wow, thanks for this guide. really informative and helpful.

    We are making the switch from DSLR’s to big boy cameras with the FS7. I am super excited and intimidated, and this guide helped a ton in understanding the science behind it all (even if it mostly went over my head).

    Thanks again!

  5. Hi Alister, and thanks for this wonderful guide !

    I would like to ask you a question. You say : “The idea is that this metadata can be used by the grading or editing software to adjust the clips exposure level in the edit or grading application so that it looks correctly exposed “.

    Is Adobe Premiere CC2014 one of this few editing software that can correct automatically exposure according to metadata, when filming in low EI ?

    If it is, is there anything that needs to be done to make it work ?

    1. At the moment there is no software that adjusts the exposure of the S-Log footage. It’s not just a case of applying different gain, you need to use a different LUT for different exposure ranges and Sony have only released a single set of LUT’s for the native ISO.

  6. Hi Alister,

    I just bought you a cocktail – I took delivery of my brand spanking new FS7 yesterday, and your website is the first place I went to to help me get a grip on its features and shooting in cine-ei.

    Many thanks for all the work you do and that you so generously share.

    Regards
    Gil

  7. Hello Alister: First off, thank you for generously sharing your extensive expertise on the shooting on SLog and using LUTs. This whole process is very new to me and as I gain knowledge I hope to be able to implement (or at least understand) much of what you have shared. I recently purchased the Sony PXW-FS7. Coming from a long career as a commercial sports still-photographer, I have moved into video in the past year using the Canon 5D and shooting ProRes via the Atomos Ninja2. I’ve gotten good results and for most of my work I am able to get quality results for my projects, but the inability to shoot higher frame rates for slomo was frustrating. Hence the FS7 purchase.

    I am thrilled with the results of my early testing, but since I don’t have a background in color grading and working with LUTs, I am a bit stuck. I am getting good quality results in Custom mode (mostly using the Standard #5 STD5 709 gamma), but of course I realize I am not utilizing the camera to it’s potential by not shooting in Cine El mode.

    I have become proficient doing my simple grading in Adobe Premiere Pro and have used Speedgrade some, but usually just use the tools within Premiere. I have used your LUTs in Premiere but can’t get my clips shot in Cine El/SLog-3 to look nearly as good (accurate, pleasing, not noisy, etc..) as the clips I have shot using the above setting in Custom mode. I realize that I have much to learn (or at least turn what I shoot over to someone more qualified), but for now I am just wondering if I am being foolish to shoot in the Custom mode. It seems the files are still better than what was I am used to coming out of the Canon/Ninja, but I hate to be not maximizing the quality of what I’m shooting. My concern is that if I shoot in Cine/SLog right now, I won’t get my clips to look as good as they would if I had just shot in Custom.

    Are any of the gamma setting in Custom mode better than other to preserve more dynamic range/color information?

    Also, I can’t seem to get your LUTs to load into the FS7 even though I have read your comments expensively assisting others with the same issue.

    Any advise is greatly appreciated. I have purchased you a Singapore Beer to offset my guilt for creating such a long post.

    Cheers!

    Tim

    1. I don’t understand the problems some people have loading LUT’s. It appears to work fine for most people, but some people do struggle.

      I would suggest learning how to use DaVinci Resolve. The Lite version is free and comes with an excellent tutorial that will get you going quite quickly. The results you will get from resolve will almost certainly be far superior to those from Premier.

  8. Just updating that I sorted out the issue loading the LUTs. I had assumed the final name would be “FXW-FS7” instead of “PMWF55_F5” (makes sense doesn’t it?). Now that I made the change, was able to load the LUT and have some nice tests to experiment with. Already, well ahead of where I was a few hours ago, so don’t worry about a reply at this point. Now your article will make much more sense. Thanks!

  9. Hi Alister, thanks for your time in putting this together. I rented an FS7 for a job a couple of weeks ago and reading through your guide before shooting was really helpful. As a stills photographer using film in a former life, this way of working is really exciting!

  10. Hi Alister, thanks for the article I’m using it to set up my FS7.
    One frustrating point: Under monitor LUT, when turning either SDI2 and/or viewfinder MLUT On I loose my waveform in the both right; even though the video signal monitor in Display on/off is selected to Waveform.
    Any idea why I’m loosing it?

    1. It’s a limitation of the image processing in the FS7. It can only add the Waveform when ALL outputs are set the same way as there is only one image processor handling this task.

  11. i am having troubles loading my LUTs as well….followed the file structure instructions (incl the change to FS7) but still only get a list of “No File”….any ideas anyone?

    either way, thanks for putting this together, i bought you a latte…

  12. ok….i got it….bizarre but i got it…it seems like the folder structure has to be as described in the article:
    PRIVATE:SONY:PRO:CAMERA:PMWF55_F5
    if the last folder is replaced with FXW_FS7 it won’t work….

  13. Thanks for the guide, a Singapore beer is yours :)) !

    One thing I don’t understand. Why is it not recommended to bake in the S-log lut internally so I don’t have to change my exposure later in the grading session ?
    I mean if I put the s-log LUT in the viewfinder and in on the cards (internal) and shoot at 1000ISO instead of 2000 won’t it be the same as what the colorist does to the image in post…darkening it one stop ?
    Doesn’t the Alexa actually do this internally as well ? I know it changes the latitude above and below middle gray similarly to what the CINE EI mode does but it always shows you the result, in the viewfinder and in the grading software ? Or does it just use metadata better ?
    Many Thanks.

    1. If you use the S-Log LUT and then use 1000EI you will see a reduction in your dynamic range. This is exactly the same as using negative gain in a conventional camera. If you subtract 1 stop (6db) from your full signal range anything near black will be reduced in level by 6db and will be lost. There will be no change to the maximum highlight range as this is limited by the sensor so no gain in highlight range. The net result is a loss of around one stop in the shadow range and no change to the high range, so the total dynamic range is reduced by one stop to 13 instead of 14. As you are opening the iris by an additional stop this will help compensate for the loss of shadow recording range, but as you are one stop more open you may encounter highlight clipping earlier.

      This isn’t in many cases a big deal, but you are sacrificing one stop of dynamic range for little benefit as you are still going to need to grade you material. Why not just record at the native ISO and gain that extra stop of shadow information?

      In raw the F5/F55/FS7 and Alexa are all exactly the same as the raw metadata includes the exposure shift which gets included during the raw de-bayer. As a result it always looks “correctly” exposed. But with Log you need a different LUT for each exposure range so you will see these differences in post.

  14. Thanks very much for the guide,
    I have one issue, I can’t turn on the Viewfinder LUT it’s greyed out and says cannot proceed when I try to select it… I don’t have the HDMI set to 4k or anything.
    Any suggestions?
    Cheers
    Brian

  15. So I don’t have an external monitor. I’m stuck with the annoying fact that I don’t have a waveform monitor when viewing the 709 LUT.
    So this is my setup
    SLOG3
    using 708 (800%) LUT
    EI (iso?) at 1000
    Trying to expose with 90% reflectance white card with zebra’s
    What should I set my zebra’s to expose properly?
    With the ei at 2000 and my zebras set to 90% and popping up with they are 90% makes sense, but when I us 1000ei shouldn’t the zebras be different? less? more?

    Thanks in advance!

    1. Zebras should be exactly the same for all EI’s. You are using EI to deliberately offset the exposure of the recordings. If you changed the zebras to compensate for the different EI you would not have the exposure offset in the recording.

  16. Gotcha. Makes sense.

    Shot this way yesterday and I am loving the results!

    Thanks for the extremely helpful info, Alister!

  17. Alister. When filming in SLog 3 cine and rating the camera at 2000EI should we over expose by a stop or two?

  18. Hello Alister, first time my post didn’t work, so I just try it again.
    What you think about rating your Camera at 3000iso, using Rec709 Lut on your viewfinder and telling your post to process the footage like material shot with 1000iso.
    It’s my run ‘n gun approach to get cleaner footage out of my FS7.
    All the best,
    Tobias Corts

  19. This was a god-send in helping me understand how LUTs really work, and how to use them effectively with my new fs7. Thank you so much for taking the time to explain it!

  20. Alister, quick question.

    I can only seem to be able to enable LUTs on the SDI-2 feed when the output setings are set to “Edge Crop”. When “Letterbox” is enabled the SDI-2 feed immediately reverts back the slog. Thoughts?

    1. Yes, this is a limitation of the cameras hardware. It can’t do the LUT processing and Letterbox function (which is an image zoom) at the same time. Edge crop is easy, just don’t use the outer pixels.

  21. Hi!
    As fresh owner of fs7, good explanation from reputable and well known cameraman is very welcome. Am longtime follower of Yor blog, from my ex1 times, as always ..well written and composed article..Thnx!
    Regards
    Raul Rooma

  22. Hello Alistair,
    this article has been incredibly insightful.
    If I can enquire about the post production process of ingesting FS7 rushes in to my grading application and applying LUT.

    I have understood rightly or wrongly that if the footage were shot in Cine El mode with SLOG3 and MLUT 709 (800) option selected. I would be required to apply the same LUT in post to correctly expose the log footage, thus ‘reverting’ it back to what was viewed on the monitor during filming.

    I cannot however seem to locate an LUT file with the 709 (800) name. Would Sony’s SGamut3CineSLog3_To_Cine+709 LUT work? Or would one of your own like the Slog3709-to-709-800-NORMAL.cube be appropriate?

    Please bear in my mind that my grading software would be Apple Color, bundled with FCP7. It does not have to my knowledge the LUT 709 (800) as pre-set.

    I apologise if this has already been raised before.

    Kind Regards,

    Bryn

  23. Thanks, Alister. Awesome article, super helpful and way better than anything from anywhere else on the internet.
    Do I get to chose if you have a beer or a coffee? I’d kind of suggest a beer, but I’ll understand if you go for coffee if it’s pre-lunch.

  24. Thanks Alister.

    As a beginner in the video world moving over from hobby 5D MK III photography to the FS7 this has been so helpful for me.

    You ever come to Thailand, please allow me to buy you more beers.

    Thanks again.

  25. Thank you so much for this tutorial, what a great guidance for beginners!

    One question, is it possible to use the zebra or waveform
    Just by looking at the image without any cards? Like you did on a dslr where you protected the important parts of the image from zebras?

    1. You can but one of the important things with this kind of workflow is consistency. If you use the 709(800) LUT then you should be OK without a white or grey card. If your exposure varies form shot to shot you will create a lot of extra work in post production.

  26. Great work Alister many thanks and enjoy the beer. I’ll study the full article in depth later this week but I have a shoot tomorrow with the FS7 and have a quick question if that’s ok. Right at the top of the article in ‘simplified’ you mention choosing an MLUTs you like in the viewfinder or monitor. As I understand it this process is as follows – (1) shoot in cine EI mode (2) select an MLUT that looks good in the viewfinder or monitor. (3) Turn that MLUT off and shoot in s-log. (4) In post drop that LUT back on to the s-log footage. Is that correct? BUT how does one drop the LUT directly on to the footage in the timeline? Thanks for your time.

    1. You don’t need to turn the LUT off while you are shooting if you only have the LUT selected for the VF. Adding the LUT in post depends on the software you are using. FCPX requires a plugin, Premiere it is done with the Lumetri color panel, Resolve it’s done by right clicking on a clip while in the color room.

  27. Thank you Alister for this complete guide and also for the presentation in Amsterdam for the FS5!
    I told you with a cocktail thank you and was surprised that no thanks came from you.

  28. HI Alister,
    Thanks for the wonderful guide that you have provided. I just have one question for you. How do I download the 709 MLUT that I used in camera so I can apply it in my color correction? I shot on CineEI Mode with the 709 MLUT and I want to apply that LUT to the footage in post, per your instruction.
    Thanks

  29. Great article. I’m confused over the exposure levels. You always describe getting white or gray levels at certain percentages, but when does your iris or shutter come into play? Does it not matter what your iris is at? I guess I don’t understand what is meant by gain vs. general exposure settings (iris, shutter). And I get further confused by the sensor always recording the same thing regardless of what your VF image looks like. Thanks for you help.

    1. With a video camera you can measure the exposure with a waveform display or zebras. Using these measurements you can then set the shutter and iris for the correct exposure which will vary depending on the brightness of the scene.

      In Cine EI the cameras recording sensitivity is fixed, even when you change the EI which only changes the LUT sensitivity.

  30. Thank you for this great article as o have used this many times over the past year for reference. Quick questions what would be proper skin tones when viewing in LC709typeA? Ire. Thanks so much

      1. Hello and thank you.

        Please, if I bake in the LC709typeA, would the correct exposure for skin tones still be 55% ?

        Also, what would be the maximum acceptable exposure for those skin tones ?

  31. Thanks Alistair. I bought your guide a few months back. I’ll buy a fs5 version if you write one too. 😉
    Can you tell me please, does rating the ISO at 800-1000, produce the same result as exposing a 90% white card at 75% (cineEI). This is Doug Jensen’s recommendation.

    1. On a FS7 if you expose S-log3 at 67% that is about 1000 EI. 75% is about 600 EI. My recommendation for 90% white is 70%.

  32. Dear Alister
    I have a quesiton ,what if i exposing in SLOG3 with LUT 709(800),and set the zerbas in 90%.but the FS7 actually recoding the slog3 flie wiht out the lut,is that meaning my scene is over exposure? cuz in cording to you sadi that slog3 correct exposure is like 61% zebras,THX

    1. It’s all, like, in the guide like. Coz u ave different exposures levels for the LUT’s as dey av diff gamma to de log like.

      1. thx, but i wanna know that will lost my highlight data of slog3 file in 709lut ’s correct exposure of highlight ?for example ,my lut already ETTR n the data are really close to the right,,is that mean the slog already over to the right(over exposure)? and thx for your patience for my poor english

        1. Don’t use LUT’s and then expose to the right. Use the LUT to expose correctly, then use the correct EI to get the appropriate exposure range. Also with log you need to learn not to worry about your highlights. It is the shadows you need to worry about. Expose the mid range correctly and highlights and shadows will fall into place correctly too. Highlights that may look over exposed when shooting will normally grade nicely (assuming you have your workflow properly setup) if the mid range has been correctly exposed.

          My advice is to use 709(800) LUT, set the EI to 800 EI and expose so the LUT’d image looks right, not over, not under. Don’t worry about the highlights.

          1. thx alot :p 1 more question ,i hear that the 709(800)lut can not display all dynamic range ,it just display 8stops(hilight and shadow data will be cut)
            and the LOOKS will show all dynamic range. its that ture? what if that ture,why we should expose in LUT?
            THX

    1. Oh okay.. good to know. I will be shooting an independent feature film next week with this camera and working with the Odyssey 7Q+ and shooting RAW. I did a test and it appears that I must really avoid anything over EI 640 (with the REC 709 (800) LUT in my viewfinder). There was virtually no noisy shadows when I looked at it with a professional colorist. The image quality was very nice. When I brought the EI to 1000 and 2000, the noise in the shadows became noticeable. Another note: my colorist and I also found that if working WITHOUT an Odyssey 7Q and recording internally with the XVAC codec, S-Log 3 / S Gamut, 4K… there was always objectionable noise (with blue artifacts) in shadow areas even when exposed properly. Even though it was acceptable for viewing on a television monitor, I had to keep in mind that this image would be viewed on a large screen at festivals and screenings. So while I love this camera, I have to shoot RAW in order to avoid potential issues in the shadows. Thank you for the info Alister.

  33. Thank you for this info, Alister! Very helpful. Question: You mentioned that working with the S-log 3/ S Gamut3.cine is easier to grade than JUST working with S-log3 (even though the S-log3 gives you the most color range of the sensor). Is that assuming one is grading this as a non-professional colorist? Is that ALSO true of working in a color suite with a professional colorist with all the tools available to him? I’d prefer to shoot my footage in a way that gets the MOST out of my sensor but don’t want it to be difficult for my colorist. Thank you.

    1. There is not normally anything to be gained by using S-Gamut3 over S-Gamut3.cine with an FS7 as the sensor cannot see any colours beyond S-Gamut3.cine so using S-Gamut3 will not give you any extra color range.

      1. Oh okay.. good to know. I will be shooting an independent feature film next week with this camera and working with the Odyssey 7Q+ and shooting RAW. I did a test and it appears that I must really avoid anything over EI 640 (with the REC 709 (800) LUT in my viewfinder). There was virtually no noisy shadows when I looked at it with a professional colorist. The image quality was very nice. When I brought the EI to 1000 and 2000, the noise in the shadows became noticeable. Another note: my colorist and I also found that if working WITHOUT an Odyssey 7Q and recording internally with the XVAC codec, S-Log 3 / S Gamut, 4K… there was always objectionable noise (with blue artifacts) in shadow areas even when exposed properly. Even though it was acceptable for viewing on a television monitor, I had to keep in mind that this image would be viewed on a large screen at festivals and screenings. So while I love this camera, I have to shoot RAW in order to avoid potential issues in the shadows. Thank you for the info Alister.

  34. Alister, would love your help in setting up my Sony FS5 for shooting Slog3 in 1080p HD. At the moment I only have the camera and no access to external monitors for things like false color, waveforms, etc. So I am sticking to zebras. What settings should I put in my Zebra 1 and Zebra 2 slot? Would appreciate the help! Thank you

      1. The zebras on the FS5 measure the actual recording level, then the gamma assist is applied over the top. I tend not to use gamma assist as it forces you to expose at the base level which is too low in my opinion. My recommendation is to set Zebra 1 to 70% and expose a white card or flat white object such as a T shirt at 70%.

  35. Hi Alister,
    Thank you very much for a great guide on Cine EI settings.
    Question: Sony FS7 Firmware update 3.0 features Support for Noise Suppression setting in Cine EI mode. If I use your guidelines described on this website (800EI or 1000EI), would you also recommend using the Noise Suppression feature and if so, which setting?
    Best regards,
    Antti

    1. No, I do not recommend the use of in camera noise reduction if you intend to grade the footage. Noise reduction works to some degree by averaging out values across areas of the image. This can result in banding in the image that only becomes noticeable after grading. It’s better to expose brightly to get a better signal to noise ratio and then if needed apply noise correction in post where you have much more control and can see the final result.

  36. Hello and thank you for this amazing article. It’s been a HUGE help!

    Just a quick question about the 709(800) LUT.

    If I am rating the FS7 at 800 ISO, thus exposing my s-log image about a stop and a third brighter to get a cleaner signal to noise ratio, do I still set my skin tones to 65-70% when viewing that LUT.

    According to Alister, it is recommended to expose S-Log 3 on the FS7 about a stop or two brighter to get the most of out of it. But, seeing as I am already doing that by rating down my camera to 800 ISO and then compensating by opening up the aperture, do I still expose skin tones at 65%? Wouldn’t that be overexposing my image 2x more than what I want to overexpose it by? Or do I still expose the 800 LUT regardless of how I rate the camera?

    Thank you!

    1. If you are using CineEI and 800EI then expose the 709(800) LUT as you would normally. The use of 800EI will give you log that is recorded 1.5 stops over base.

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