Category Archives: Shooting Tips

How I shoot the Northern Lights

460x150_xdcam_150dpi How I shoot the Northern Lights

Every year as many of my regular readers will know  I run tours to the very north of Norway taking small groups of adventurers well above the arctic circle in the hope of seeing the Aurora Borealis or Northern Lights. I have been doing this for around 20 years and over the years as cameras have improved it’s become easier and easier to video the Aurora in real time so that what you see in the video matches what you would have seen if you had been there yourself.

In the past Aurora footage was almost always shot using long exposures and time lapse sometimes with photo cameras or with older video cameras like the Sony EX1 or EX3 which resulted in greatly sped up motion and the loss of many of the finer structures seen in the Aurora. I do still shoot time lapse of the Aurora using still photos, but in this video I give you a bit of behind the scenes look at one of my trips with details of how I shoot the Aurora with the Sony FX3 in real time and also with the FX30 using S&Q motion. The video was uploaded in HDR so if you have an HDR display you should see it in HDR, if not it will be streamed to you in normal standard dynamic range. The cameras used are Sony’s FX3 and FX30. The main lenses are the Sony 24mm f1.4 GM and 20mm f1.8 G but when out and about on the snow scooters I use the Sony 18-105 G power zoom on the FX30 for convenience.

I used the Flexible ISO mode in the cameras to shoot S-Log3 with the standard s709 LUT for monitoring. I don’t like going to crazy high ISO values as the images get too noisy, so I tend to stick to 12,800 or 25,600 ISO on the FX3 or a maximum  of 5000 ISO on the FX30 (generally on the FX30 I stay at 2500). If the images are still not bright enough I will use a 1/12th shutter speed at 24fps. This does mean that pairs of frames will be the same, but at least the motion remains real-time and true to life.

If that still isn’t enough rather than raising the ISO still further I will go to the cameras S&Q (slow and quick) mode and drop the frame rate down to perhaps 8fps with a 1/8th shutter, 4fps with a 1/4 shutter or perhaps all the way down to 1fps and a 1 second shutter.  But – once you start shooing at these low frame rates the playback will be sped up and you do start to loose many of the finer, faster moving and more fleeting structures within the aurora because of the extra motion blur. 

So much of all of this will depend on the brightness of the Aurora. Obviously a bright Aurora is easier to shoot in real time than a dim one. This is where patience and perseverance pays off. On a dark arctic night if you are sufficiently far north the Aurora will almost always be there even if very faint. And you can never be sure when it might brighten. It can go from dim and barely visible to bright and dancing all across the sky in seconds – and it can fade away again just as fast. So, you need to stay outside in order to catch the those often brief bright periods. On my trips it is not at all unusual for the group to start the evening outside watching the sky, but after a couple of hours of only a dim display most people head inside to the warm only to miss out when the Aurora brightens. Because of this we do try to have someone on aurora watch.

During 2024 we should be at the peak of the suns 11 year solar cycle, so this winter and next winter should present some of the best Aurora viewing conditions for a long time to come. My February 2024 Norway trip is sold out but I can run extra trips or bespoke tours if wanted so do get in touch if you need my help. There is more information on my tours here: https://www.xdcam-user.com/northern-lights-expeditions-to-norway/

Don’t forget I also have information on filming in cold weather here: https://www.xdcam-user.com/2023/12/filming-in-very-cold-weather/

I will be back in Norway from the 1st of February, keep an eye out for any live streams, I will be taking an Accsoon SeeMo to try to live stream the Aurora.

Filming in very cold weather

It’s that time of year again where for those of us that live in the more northern parts of  Northern Hemisphere the weather really starts to turn cold. So, once again I have updated my guide to filming in the cold which can be found by clicking here. 

I will be off to Norway again in January to shoot the Northern lights, something I do every lear and over the years I’ve worked in temperatures down to -45c. 

Super simple FX30 time-lapse.

Those of you that follow me on facebook will know that recently I have been travelling a lot. A couple of days ago I arrived in Dubai and I have been staying on a pretty high floor of the  Dusit Thani hotel. I didn’t ask for a room with a view, but I got one. From my bedroom window I could see the iconic Burj Kahlifa tower and parts of one of Dubai’s major roads.  I also had my FX30 with me, so I felt I should take advantage of this view and shoot a time-lapse going from day to night.

Easy Peasy Lemon Squeezy!

Fortunately this is a pretty easy thing to do with the FX30. I didn’t use the cameras video modes, instead I used it in the “P” program auto photo mode. In this mode the camera automatically sets the aperture and shutter speed to suit the available light levels. As the light level decreases the aperture will open up until it can’t open any more and then the shutter speed will become longer. 

So, all YOU need to do is determine the ISO at which you want to shoot. I chose 125 ISO (I used picture profile 11 – S-Cinetone) as this will give the lowest possible noise level and in addition for shots at night it will force the shutter speed to become quite long as the light levels fall. The longer shutter will then cause the lights of any cars on the roads to become blurred and form pleasing trails. 

To shoot the sequence of still frames that would ultimately be turned into a video clip I used the FX30’s built in time-lapse photo mode (Menu – Shooting – Drive Mode – Interval Shoot Function). I set the start time to 1 sec which is the minimum and means the the camera will start shooting the sequence 1 second after you press the shutter release. I set the shooting interval to 3 seconds and the number of shots to 3000 as this would cover the full duration of the day to night shot that I wanted (about 2.5 hours).

To power the camera for a couple of hours I used my Macbook Pro’s power supply with a USB-C cable going to the FX30’s USB-C port. As an alternative you could also use a  powerbank that has a USB-C PD port (USB-C Power Deliver). 

To position the camera I used a soft pillow (I didn’t have a tripod with me). I used manual focus and double, triple checked the focus with the lens wide open to ensure it was sharp.

A common issue when shooting through a window is reflections of objects inside the room or light from in the room falling on the often dirty window. Unless the rooms curtains are black, closing the curtains doesn’t help as the outside light tends to reflect back off the curtains onto the window. To prevent this I used a couple of black T-Shirts wrapped around the camera and lens to block any light from reflecting off the window and kept the room lights off.

All that was then left was to press the shutter release and allow the camera to take the  images that would make up the sequence. I shot both raw an jpeg. The jpegs would allow me to very quickly preview the end result (and in fact the jpegs were used for the video linked here). The raw frames can be used when you need the very highest quality and will give you greater grading flexibility compared to the 8 bit jpegs.

Once the sequence was shot I then dropped the jpegs into a DaVinci Resolve project, Resolve will bring in sequentially numbered jpeg and tiff files as a single video clip, so editing and grading is easy. I haven’t yet worked on the raw files, but my workflow with these normally involves using Photoshop to adjust and grade a single frame and then use Adobe Bridge to batch process and then export all the frames as tiff files using the same grading settings.

All in all it took me about 15 to 20 minutes to set the camera up. Most of that was time spent figuring out how to best place the black shirts to prevent reflections. Then I went out for diner while the camera shot the sequence over a couple of hours and finally I spent about 45 minutes doing a bit of an animation and a few colour tweaks in Resolve. Because the FX30 still frames are 6.2K x 4.1K there is plenty of resolution to crop in a bit and create a move within the image, even when delivering in 4K.  So, for very little actual time spent, I got a quite nice little time-lapse sequence.

The Sony FX30 is really growing on me. I also own the FX3, the FX6 and the FX9. But when I am travelling the FX30 is now my go-to camera. When combined with the 18-105 power zoom lens you have a low cost and lightweight package that really does deliver great looking images. The 6K oversampled to 4K recordings have a texture and quality to them that I find really pleasing. In the Venice workshop we did here in Dubai we put my FX30 side by side with the Venice and the audience members were quite shocked by how close they are. But then this is the whole point of the cinema line – to provide a range of cameras to suit all budgets and a vast range of applications that all look more or less the same.

Of course the Venice image is that bit better, the 16 bit encoding and X-OCN makes the footage a delight to grade and the textures in the deepest shadows are clearer and finer. The way Venice handles highlights is just that little bit better. All around there are very subtle things about the Venice image that are better. But the FX30 really does produce a remarkably good image for very little money.

Not all ND filters are created equal.

Over the last 2 weeks I have been shooting some tests for a major feature film. The tests involved a special process that involves the use of  Infrared light and shooting outdoors. 

On the test day we had some fairly bright light levels to deal with. So as you would normally do we added some ND filtration to reduce the light levels. Most of the equipment for the shoot was on hire from Panavision, the main cameras being Panavised Sony Venices with PV70 mounts and Panavison lenses. But for reasons I can’t go into yet, we were unable to use the Venice internal ND filters, so we had to use external ND’s.

The first ND’s we used were circular Tiffen IRND’s that were the correct size for the PV lenses. But much to my surprise these made very little difference to the amount of IR reaching the camera. For our application they were absolutely no good. Fortunately, I had a set of Formatt Hitech IRND’s in my camera bag and when we tried these we got an equal visible and infrared cut. So, the Tiffen’s were put back in their boxes and the Formatt filters used instead.

Back at Panavision we did some further testing and found that both the Tiffen and Schnieder IRND’s that we tested had very little IR cut. But the Formatt Hitech and Panavision IRND’s that we tested cut the IR by a very similar amount to the visible light. In addition we were able to test the Venice built in ND filters and found that these too did a very good job at cutting both IR and visible light by similar amounts.

So, my recommendation is – if you are ever concerned about infrared light contaminating  your images use a Venice 2 with it’s built in ND’s, Panavision or Formatt Hitech IRND’s.

Zebras and Log – Use a narrower window/range.

If you are using Zebras to measure the exposure of a log gamma curve you should consider using a narrower Zebra window.

Why?

From middle grey to white (50% to 90%) in the world of standard dynamic range Rec-709 each stop occupies approximately 16% of the recording range. Typically the default zebra window or zebra range used by most cameras is 10% (often +/- 5%). So, when Zebras are set to 70% they will appear at 65% and go away at 75%. For Rec-709 and most conventional SDR gammas this window or range is around 3/4 of a stop, so less than 1 full stop and generally reasonably accurate.

But if using most Cineon based log curves, such as Sony’s S-Log3, between middle grey and white (41% to 61%) each stop only occupies around 8% of the recording range, half the range used by Rec-709. As a result if you use a default 10% zebra window, zebras will appear over a 1.2 stop range, this is excessive and introduces a large margin of exposure error. Compared to Rec-709 the zebras will only be half as precise, especially if you are trying to measure the brightness of a grey card or white card.


I recommend reducing the width of the Zebra window to 6% when using Zebras to measure skin tones within the S-Log3 image (if measuring a Rec-709 LUT there is no need to change the window). This will then give a similar range and accuracy to a 10% window in 709. If you are using zebras to measure a white card or grey card then consider bringing the zebra window down to 2%  to gain a more accurate reading of the white/grey card.

fx-cameras-zebras_4.32.1-scaled Zebras and Log - Use a narrower window/range.
FX6(left) and FX3 (right) zebras set to measure S-Log3 white card exposure.


The zebra window or range can normally adjusted in the cameras menu under the zebra settings. On the Sony Alpha’s and and FX3/FX30 you can adjust the range of the C1 and C2 custom zebras.

Microphone Latency – Don’t mix and match!

This tripped me up recently and I really should know better.

Don’t mix wireless and cabled microphones with differing amounts of latency because if you do you may have a nasty and difficult to remove echo or phase issues in your audio. 

Digital + Analog don’t mix well.

In my particular case I was using a couple of Sony UWP-D wireless microphones to mic up two out of 3 members of a discussion panel. For the 3rd member I had planned to use another UWP-D but that microphone became unavailable at the last minute, so instead I used a lower cost digital microphone that works on the 2.5Ghz band. There is absolutely nothing fundamentally wrong with this lower cost microphone but the digital processing and transmission adds a very slight delay to the audio.

The Sony UWP-D’s are extremely low latency (delay) microphones and the audio arrives at the camera almost instantly. However most of the lower cost digital microphones have a very slight delay. That delay may be 1 frame or less, but there is still a delay. So the audio from the digital microphone arrives at the camera slightly late. If this is the only microphone you are using this isn’t an issue. But if you mix a very low latency microphone with one with a very slight delay, if both mics pick up any of the same sounds in the background there will be an echo or possibly a phase issue.

As the delay is almost never exactly 1 frame  this can be difficult to resolve in most normal video post production suites where you can only shift things in 1 frame increments.

Phase Issues:

Phase issues occur when the audio from one source arrives very slightly out of sync with the other so that the one source cancels certain frequencies of the other out when the two are mixed together. This can make the audio sound thin or have a reduced frequency response.

So… don’t mix different types of digital wireless microphones and don’t mix lower cost digital microphones with more expensive low latency microphones. And when you are checking and monitoring your audio listen to a full mix of all your audio channels. If you monitor the channels separately the echo or any phasing issues might not be heard.

Low Light Shooting – S-Log3 or S-Cinetone?

A fundamental aspect of electronic cameras is that the bulk of the noise comes from the sensor. So the amount of noise in the final image is mostly a function of the amount of light you put on to the sensor v the noise the sensor produces (which is more or less constant). This is known as the signal to noise ratio, often abbreviated to SNR.

Whether you use S-Log3 or S-Cinetone, even though the base ISO number the camera displays changes the sensitivity of the camera is actually the same, after all we are not changing the sensor when we change modes. In fact if you set the camera to dB you will see that in custom mode the base for both S-Cinetone and S-log3 (and every other gamma curve) is always 0dB.

All we are changing when we switch between S-Cinetone and S-Log3 is the gamma curve – which is a form of gain curve. The base ISO number changes between S-Log3 and S-Cinetone because if you were using an external light meter this would be the number to put into the meter to get the “correct” exposure, but the actual sensitivity of the camera remains the same.

First let’s think about what is happening at the base ISO of each if we were to use an external light meter to set the exposure…..

If we shoot at S-Cinetone and use the 320 ISO value in the light meter the aperture will be a little over a stop more open than if you shoot with S-Log3 and use 800 ISO for the light meter. So when using S-Cinetone at the base ISO there is a little over twice as much light going on to the sensor compared to S-Log3 at the base ISO and as a result the S-Cinetone will be much less noisy than the S-Log3. Not because of a sensitivity or noise performance difference but simply because you are exposing the sensor more brightly.

And if we use the SAME ISO value for S-Cinetone and S-Log3?

So now think about what might happen if you were to put 400 ISO into your light meter and use the values for shutter and aperture the meter gives and shoot with either S-Cinetone or S-Log3 using the very same aperture and shutter settings so that the same amount of light is hitting the sensor for both. The result will be that the amount of noise in the resulting image will be broadly similar for both and the same would happen if you were to use, let’s say, 4000 ISO (assuming you switch to high base for both).

There will tend to be a bit more noise in the S-Log and CineEI at the default settings, because by default NR is turned off in CineEI. But with the same in camera NR settings, again both the S-Log3 and S-Cinetone will have very, very similar noise levels when the sensor receives the same amount of light.

What about when there isn’t enough light?

So – when you are struggling for light, both will perform similarly from a noise point of view. BUT where there may be a difference is that with S-Cinetone all your image processing is done before it is compressed by the codec and what you see in the viewfinder is what you get. With S-Log3 the “underexposed” image gets compressed and then you will need to process that in post and when you add your post corrections this will be to the recorded image + compression artefacts so there will always be a lot of uncertainty as to how the final image will come out.

Personally I tend to favour S-Cinetone for under exposed situations. Generally if it’s under exposed dynamic range isn’t going to be an issue. S-Cinetone also spreads what image information you do have over a greater range of code values than S-Log3 and this may also help a little. But there is no right or wrong way and any differences will be small.

Timecode doesn’t synchronise anything!!!

There seems to be a huge misunderstanding about what timecode is and what timecode can do. I lay most of the blame for this on manufactures that make claims such as “Our Timecode Gadget Will Keep Your Cameras in Sync” or “by connecting our wireless time code device to both your audio recorder and camera everything will remain in perfect sync”. These claims are almost never actually true.

What is “Sync”.

First we have to consider what we mean when we talk about “sync” or synchronisation.  A dictionary definition would be something like “the operation or activity of two or more things at the same time or rate.” For film and video applications if we are talking about 2 cameras they would be said to be in sync when both start recording each frame that they record at exactly the same moment in time and then over any period of time they record exactly the same number of frames, each frame starting and ending at precisely the same moment.

What is “Timecode”.

Next we have to consider what time code is. Timecode is a numerical value that is attached to each frame of a video or an audio recording in an audio device to give it a time value in hours, minutes, seconds, frames. It is used to identify individual frames and each frame must have a unique numerical value. Each individual successive frames timecode value MUST be “1” greater than the frame before (I’m ignoring drop frame for the sake of clarity here). A normal timecode stream does not feature any form of sync pulse or sync control, it is just a number value.

Controlling the “Frame Rate”.


And now we have to consider what controls the frame rate that a camera or recorder records at. The frame rate the camera records at is governed by the cameras internal sync or frame clock. This is normally a  circuit controlled by a crystal oscillator. It’s worth noting that these circuits can be affected by heat and at different temperatures there may be very slight variations in the frequency of the sync clock. Also this clock starts when you turn the camera on, so the exact starting moment of the sync clock depends on the exact moment the camera is switched on. If you were to randomly turn on a bunch of cameras their sync clocks would all be running out of sync. Even if you could press the record button on each camera at exactly the same moment, each would start recording the first frame at a very slightly different moment in time depending on where in the frame rate cycle the sync clock of each camera is. In higher end cameras there is often a way to externally control the sync clock via an input called “Genlock”.  Applying a synchronisation signal to the cameras Genlock input will pull the cameras sync clock into precise sync with the sync signal and then hold it in sync. 

And the issue is………..

Timecode doesn’t perform a sync function. To SYNCHRONISE two cameras or a camera and audio recorder you need a genlock sync signal and timecode isn’t a sync signal, timecode is just a frame count  number. So timecode cannot synchronise 2 devices. The camera’s sync/frame clock might be running at a very slightly different frame rate to the clock of the source of the time code. When feeding timecode to a camera the camera might already be part way through a frame when the timecode value for that frame arrives, making it too late to be added, so there will be an unavoidable offset. Across multiple cameras this offset will vary, so it is completely normal to have a +/- 2 frame (sometimes more) offset amongst several cameras at the start of each recording.

And once you start to record the problems can get even worse…

If the camera’s frame clock is running slightly faster than the clock of the TC source then perhaps the camera might record 500 frames but only receive 498 timecode values – So what happens for the 2 extra frames the camera records in this time? The answer is the camera will give each frame in the sequence a unique numerical value that increments by 1, so the extra frames will have the necessary 2 additional TC values. And as a result the TC in the camera at the end of the clip will be an additional 2 frames different to that of the TC source. The TC from the source and the TC from the camera won’t exactly match, they won’t be in sync or “two or more things at the same time or rate”, they will be different.

The longer the clip that you record, the greater these errors become as the camera and TC source drift further apart.

Before you press record on the camera, the cameras TC clock will follow the external TC input. But as soon as you press record, every recorded  frame MUST have a unique new numerical value 1 greater than the previous frame, regardless of what value is on the external TC input. So the cameras TC clock will count the frames recorded. And the number of frames recorded is governed by the camera sync/frame clock, NOT the external TC.  

So in reality the ONLY way to truly synchronise the timecode across multiple cameras or audio devices is to use a sync clock connected to the  GENLOCK input of each device.

Connecting an external TC source to a cameras TC input is likely to  result in much closer TC values for both the audio recorder and camera(s) than no connection at all. But don’t be surprised if you see small 1 or 2 frame errors at the start of clips due to the exact timing of when the TC number arrives at the camera relative to when the camera starts to record the first frame and then possibly much larger errors at the ends of clips, these errors are expected and normal. If you can’t genlock everything with a proper sync signal, a better way to do it is to use the camera as the TC source and feed the TC from the camera to the audio recorder. Audio recorders don’t record in frames, they just lay the TC values alongside the audio. As an audio recorder doesn’t need to count frames the TC values will always be in the right place in the audio file to match the cameras TC frame count. 

CineEI is not the same as conventional shooting.

CineEI is different to conventional Shooting and you will need to think differently.

Shooting using CineEI is a very different process to conventional shooting. The first thing to understand about CineEI and Log is that the number one objective is to get the best possible image quality with the greatest possible dynamic range and this can only be achieved by recording at the cameras base sensitivity. If you add in camera gain you add noise and reduce the dynamic range that can be recorded, so ideally you always need to record at the cameras base sensitivity for the best possible captured image.

Sony call their system CineEI. On an Arri camera the only way to shoot log or raw is using Exposure Indexes and it’s the same with Red, Canon and almost every other digital cinema camera when shooting log. You always record at the cameras base sensitivity because this will deliver the greatest dynamic range.

Post Production.

A key part of any log workflow is the post production. Without a really good post production workflow you will never see the best possible results from shooting Log. An important part of the post production workflow will be correcting for any exposure offsets used when shooting. If something has been exposed very brightly, then in post you will bring that exposure down to a normal level. Bringing the levels down in post will decrease noise. The flip side to this is that if the exposure is very dark then you will need to raise the levels in post and this will make then more noisy

Exposure and Light Levels.

It is assumed that when using CineEI and shooting with log that you will control the light levels in your shots and use levels suitable for the recording ISO (base ISO) of the camera using combinations of aperture, ND and shutter speed, again it’s all about getting the best possible image quality. If lighting a scene you will light for the base ISO of the camera you are using.

Here’s the bit that’s different:

Changing the EI (Exposure Index) allows you to tailor where the middle of your exposure range is. It allows you to alter the balance between more highlight range with less shadows or less highlight range with more shadow information in the captured image. On a bright high contrast exterior you might want more highlight range, while for a dark moody night scene you might want more shadow range. Exposing brighter puts more light on to the sensor. More light on the sensor will extend the shadow range but decrease the highlight range. Exposing darker will decrease the shadow range but also allow brighter highlights to be captured without clipping. 

IMPORTANT:   EI is NOT the same as ISO.

ISO is a measure of a film stock or camera sensors SENSITIVITY to light. It is the measure of how strongly the cameras sensor responds to light.

Exposure Index is a camera setting that determines how bright the image will become for a given EXPOSURE. While it is related to sensitivity it is NOT the same thing and should always be kept distinct from sensitivity.

ISO= Sensitivity and a measure of the sensors response to light.

EI = Exposure Index – how bright the image seen in the viewfinder will be.

The important bit to understand is that EI is an exposure rating, not a sensitivity rating. The EI is the number you would put into a light meter for the optimum EXPOSURE for the type of scene you are shooting. The EI that you use depends on your desired shadow and highlight ranges as well as how much noise you feel is acceptable. 

What Actually happens when I change the EI value on a Sony camera?

On a Sony camera the only things that change when you alter the EI value are the brightness of any Look Up Tables (LUTs) being used, the EI value indicated in the viewfinder and the EI value recorded in the metadata that is attached to your clip.

Importantly – To actually see a change in the viewfinder image or the image on an external monitor you must be viewing your images via a LUT as the EI changes the LUT brightness, changing the EI does not on it’s own change the  way the S-Log3 is recorded or the sensitivity of the camera. If you are not viewing via a LUT you won’t see any changes when you change the EI values, so for CineEI to work, you must be monitoring via a LUT.

CineEI-diagram-1-scaled CineEI is not the same as conventional shooting.

Raising and Lowering the EI value:

When you raise the EI value the LUT will become brighter. When you lower the EI value the LUT will become darker.

If we were to take a camera with a base ISO of 800 then a nominal  “normal” exposure would result from using 800 EI. When the base ISO value and the EI value are matched, then we can expect to get a “normal” exposure.

CineEI-base-exp-scope-scaled CineEI is not the same as conventional shooting.
The S-Log3 levels that you will get when exposed correctly and the EI value matches the cameras base ISO value. Note you will have 6 stops of range above middle grey and 8+ stops below middle grey.

 

Let’s now look at what happens when we use EI values higher or lower than the base ISO value.

(Note: One extra stop of exposure is the equivalent of doubling the ISO or EI. One less stop of exposure is the equivalent of halving the ISO or EI. So if double 800 EI so you get to 1600 EI this would be considered 1 stop higher. If you double 1600 EI so you are at 3200 EI this is one further stop higher. So 800 EI to 3200 EI is 2 stops higher)

If you were to use a higher EI, let’s say 3200 EI, two stops higher than the base 800 EI, then the LUT will become 2 stops brighter.

If you were using a light meter you would enter 3200  into the light meter. 

When looking at this now 2 stops brighter viewfinder image you would be inclined to close the aperture by 2 stops (or add ND/shorter shutter) to bring the brightness of the viewfinder image back to normal. The light meter would also recommend an exposure that is 2 stops darker.

CineEI-diagram-high-EI-scaled CineEI is not the same as conventional shooting.

Because the recording sensitivity or base ISO remains the same no matter what the EI, the fact that you have reduced your exposure by 2 stops means that the sensor is now receiving 2 stops less light, however the recording sensitivity  has not changed. 

Shooting like this, using a higher EI than the base ISO will result in less light hitting the sensor which will result in images with less shadow range and more noise but at the same time a greater highlight range.

CineEI-high-ei-scope-scaled CineEI is not the same as conventional shooting.
The S-Log3 levels that you will get when the EI value is 2 stops higher than the cameras base ISO value and you have exposed 2 stops darker to compensate for the brighter viewfinder image. Note how you now have 8 stops above middle grey and 6+ stops below. The final image will also have more noise.

 

A very important thing to consider here is that this is not what you normally want when shooting darker scenes, you normally want less noise, more shadow range. So with CineEI, you would normally try to shoot a darker, moody scene with an EI lower than the base ISO.

Screenshot-2022-02-11-at-10.15.43-600x270 CineEI is not the same as conventional shooting.
In this chart we can see how at 800 EI there is 6 stops of over exposure range and 9 stops of under. At 1600 EI there will be 7 stops of over range and 8 stops of under and the image will also be twice as noisy. At 400 EI there are 5 stops over and 10 stops under and the noise will be halved.



This goes completely against most peoples conventional exposure thinking.

For a darker scene or a scene with large shadow areas you actually want to use a low EI value. So if the base ISO is 800 then you might want to consider using 400 EI. 400 EI will make the LUT 1 stop darker. Enter 400 EI into a light meter and compared to 800 the light meter will recommend an exposure that is 1 stop brighter. When seeing an image in the viewfinder that is 1 stop darker you will be inclined to open the aperture or reduce the ND to bring the brightness back to a normal level. 

CineEI-diagram-low-EI-scaled CineEI is not the same as conventional shooting.

This now brighter exposure means you are putting more light on to the sensor, more light on the sensor means less noise in the final image and an increased shadow range. But, that comes at the loss of some of the highlight range.

CineEI-low-ei-scope-scaled CineEI is not the same as conventional shooting.
The S-Log3 levels that you will get when the EI value is 2 stops lower than the cameras base ISO value and you have exposed more brightly to compensate for the darker viewfinder image. Note how you now have 4 stops above middle grey and 10+ stops below. The final image will have less noise.

 

Need to think differently.

The CineEI mode and log are not the same as conventional “what you see is what you get” shooting methods. CineEI requires a completely different approach if you really want to achieve the best possible results.

If you find the images are too dark when the EI value matches the recording base ISO, then you need to open the aperture, add light or use a faster lens. Raising the EI to compensate for a dark scene is likely to create more problems than it will fix. It might brighten the image in the viewfinder, making you think all is OK, but on your small viewfinder screen you won’t see the extra noise and grain that will be in the final images once you have raised your levels in post production. Using a higher EI and not paying attention could result in you stopping down a touch to protect some blown out highlight or to tweak the exposure when this is probably the last thing you actually want to do.

I’ve lost count of the number of times I have seen people cranking up the EI to a high value thinking this is how you should shoot a darker scene only to discover they can’t then make it look good in post production. The CineEI mode on these cameras is deliberately kept separate from the conventional “custom” or “SDR” mode to help people understand that this is something different. And it really does need to be treated differently and you really do need to re-learn how you think about exposure. 

For dark scenes you almost never want to use an EI value higher than the base ISO value and often it is better it use a lower EI value as this will help ensure you expose any shadow areas sufficiently brightly.

The CineEI mode in some regards emulates how you would shoot with a film camera. You have a single film stock with a fixed sensitivity (the base ISO). Then you have the option to expose that stock brighter (using a lower EI) for less grain, more shadow detail, less highlight range or expose darker (using a higher EI) more grain, less shadow detail, more highlight range. Just as you would do with a film camera.

Sony’s CineEI mode is not significantly different from the way you shoot log or raw with an Arri camera. Nor is it significantly different to how you shoot raw on a Red camera – the camera shoots at a fixed sensitivity and any changes to the ISO value you make in camera are only actually changing the monitoring brightness and the clips metadata.

Exposing more brightly on purpose to achieve a better end result is not “over exposure”. It is simply brighter exposure. Over exposure is generally considered to be a mistake or undesirable, but exposing more brightly on purpose is not a mistake.

Handy Tips For Using The Sony Variable ND Filter Values.

Sony rate the ND filters in most of there cameras using a fractional value such as 1/4, 1/16, 1/64 etc.

These values represent the amount of light that can pass through the filter, so a 1/4 ND lets 1/4 of the light through. 1/4 is the equivalent to 2 stops ( 1 stop = half,  2 stops = 1/4,  3 stops = 1/8,  4 stops = 1/16,  5 stops = 1/32, 6 stops = 1/64,  7 stops = 1/128).


These fractional values are actually quite easy to work with in conjunction  with the cameras ISO rating.

If you want to quickly figure out what ISO value to put into a light meter to discover the aperture/shutter needed when using the camera with the built in ND filters, simply take the cameras ISO rating and multiply it by the ND value. So 800 ISO with 1/4 ND becomes 800 x 1/4 = 200 (or you can do the maths as 800 ÷ 4). Put 200 in the light meter and it will tell what aperture to use for your chosen shutter speed.

If you want to figure out how much ND to use to get an equivalent overall ISO rating (camera ISO and  ND combined) you take the ISO of the camera and divide by the ISO you want and this gives you  a value “x” which is the fraction in 1/x. So if you want 3200 ISO then take the base of 12800 and divide by 3200 which gives 4, so you want 1/4 ND at 12800.