Tag Archives: LUT

Understanding Sony’s Viewfinder Display Gamma assist.

Most of sony’s cameras that support S-Log3 or Hybrid Log Gamma also have a function called Viewfinder Display Gamma Assist.

Viewfinder Display Gamma Assist allows you to monitor with the cameras built in LCD screen or viewfinder with the correct brightness and contrast range when using gamma curves that are not directly compatible with these Rec-709 screens.

Whenever you try to view a gamma curve that is not normal Rec-709 on a Rec-709 screen the brightness and contrast that you will see will be incorrect. The most common scenario is perhaps viewing S-Log3 without any form of LUT. In this case the images will look less bright and have less contrast than they should and this makes judging exposure difficult and as well as making it less easy to see focus errors.

With a camera like the FX6 or FX9 most people will use the cameras CineEI mode and add a LUT to the viewfinder image to convert the S-Log3 to something that looks more contrasty and on the FX6 and FX9 the default LUT is “s709”.  However s709 is not the same thing as Rec-709.

I think a lot of people think that the default s709 LUT is the same as Rec-709, it’s not, it is very different. They look very different and result in quite different brightness levels when exposed correctly. s709 when exposed correctly will put skin tones somewhere around 50-60% and white at 78%. If you expose s709 using normal Rec-709 brightness levels (70% skintones, 90% white) this is actually over exposed by just over 1 stop. As a result if you expose the s709 LUT, using Rec-709 levels, and then turn off the LUT and instead use Viewfinder Gamma Assist, the gamma assist will look wrong, it will be too bright and may look washed out and this is simply because the exposure IS wrong.

Almost always, if the viewfinder display gamma assist looks wrong, the exposure is wrong. When it looks right, the likelihood is the exposure is right.

A few things to understand:
  • The viewfinder is a Rec-709 range display device only capable of showing Rec-709 range and colour.
  • Feed true Rec-709 to a Rec-709 device and you will have a correct looking image with “normal” brightness, contrast and colour.
  • Feed S-Log3 to a Rec-709 device and you will have an incorrect dull, flat looking image due to the gamma miss-match between the capture gamma and display gamma.
  • Feed S-Log3 to a device with S-Log3 gamma and you will once again have the correct brightness and contrast as there is no longer a gamma miss-match (S-Log3 only appears to be flat due to the gamma missmatch between S-Log3 and Rec-709, use the right gamma and you will see that it is not actually flat).

Viewfinder Display Gamma Assist works by changing the gamma curve used in the Viewfinder to a gamma curve similar to S-Log3. When you view S-Log3 with S-Log3 gamma you will have the correct contrast and brightness, so correct exposure will look correct.

But because the cameras LCD display screen can only show 6 to 7 stops you don’t get the full S-Log3 viewing range, just the central mid range part that is the direct equivalent of Rec-709. This very closely matches what you see if you use the Sony 709(800) LUT to convert the S-log3 to 709. The 709(800) LUT converts S-Log2 or S-Log3 to vanilla Rec-709 (70% skintones/90% white) with a knee that provides a slightly extended highlight range. It is broadly comparable to how most conventional Rec-709 cameras will look. So as a result viewfinder display gamma assist and Sony’s 709(800) LUT’s will look almost identical, while the s709 LUT will (and should by design) look different.


Viewfinder Display Gamma Assist is extremely useful for scenarios where you do not have a LUT option. It can help you make good exposure assessments. It can make it easier to see when you are in focus. But it isn’t a LUT, so can’t be applied to the cameras outputs, only the built in viewfinder. Additionally if you use zebras, the waveform or histogram, gamma assist has no effect on these so you must remember that you are still measuring the levels f the actual recording gamma, not Rec-709 levels.

Viewfinder Gamma Assist is useful not only for shooting with S-Log but also when shooting using HLG (Hybrid Log Gamma). HLG is an HDR gamma curve and because the LCD viewfinder isn’t HDR you can’t correctly monitor HLG directly. Viewfinder Gamma Assist allows you to monitor with the correct brightness and contrast when shooting HLG making it easier to confidently get the correct exposure levels, as much like S-log3 the levels required for the correct exposure of HLG are quite different to Rec-709.

One last thing: NEVER use Viewfinder Gamma Assist with a LUT at the same time, this will result in a completely incorrect looking image and could result in very bad exposure as a result.

FX6 Guide to Cine EI – Update To Include StRange PlayBack EI Levels.

I’ve added some updates to my guide to using the Cine EI Mode in the FX6 (towards the bottom) to cover the strange playback behavior where the EI levels are reversed.  This can result in some very misleading brightness levels during playback that might make you think you exposed incorrectly. 
http://www.xdcam-user.com/2020/12/a-guide-the-the-fx6s-cineei-mode/

A Guide the the FX6’s CineEI Mode.

Mode-CineEI1_1.1.1-1024x576 A Guide the the FX6's CineEI Mode.
The FX6 CineEI mode can be enabled via status page 4 or via the main menu and project settings.

 

WHAT IS CINE EI?

The FX6’s CineEI mode is designed to make shooting using S-Log3 or raw easy and straightforward. It optimises the camera so that settings such as the recording ISO, noise reduction and sharpening are all optimised for recording either S-Log3 or raw with the best possible dynamic range.

Mode-CineEI2_1.1.1-600x338 A Guide the the FX6's CineEI Mode.

It also makes sure that the S-Log3 or raw recordings are optimised for grading. In addition you can use a LUT (Look Up Table) in the viewfinder or on the HDMI/SDI output to provide an approximation of how your footage will look after it’s been graded as well as to assist you in getting the exposure right.

HINT: What is a LUT? A LUT is a simple Look Up Table of input values that represent different levels in the recording format (in this case S-Log3) and then converts those input values to new output values that are appropriate for the monitor or display range you are using. This conversion can included stylised adjustments to give the output image a specific look.

Once you have a LUT enabled and you are viewing the LUT either in the viewfinder or on a monitor an exposure offset can be applied to the LUT to make it darker or brighter than normal. This LUT brightness offset is used to allow you to deliberately offset how bright the recordings are, this is the “EI” or Exposure Index part of CineEI. More on that later.

BUILT IN LUTS

The FX6 has 3 built in LUTs, but in addition to the built in LUTs you can load your own “user LUTs” into the camera as what the FX6 calls “Base Looks” making this a very flexible and capable system. If you want to load you own LUTs into the camera these must be 3D Cube LUT’s and should be placed in the — Private : SONY : PRO : LUT folder of an SD card or CFExpress card that has been formated in card slot 2 of the FX6.  The LUT’s should be 17x or preferably 33x cube LUT’s designed for use with S-Log3 and SGamut3.cine. They are loaded via the main menu PAINT – BASE LOOK page.

lut-selection_1.1.1-600x338 A Guide the the FX6's CineEI Mode.
The FX6 has 3 included LUT’s, these are s709, 709(800) and S-Log3. The AC-BCST LUT seen here is a user LUT that has been saved to the camera.

 

CODEC CHOICE.

As your material will require grading in post production, if you are shooting UHD or 4K you should NOT use XAVC-L because in UHD/4K XAVC-L is 8 bit 4:2:0. A much better choice is XAVC-I which is always 10 bit 4:2:2 and/or raw.

FIXED RECORDING ISO.

Once the camera is set to use the CineEI mode the recording sensitivity is fixed to either 800 ISO when in Lo Base sensitivity or 12,800 ISO when the camera is set to Hi Base sensitivity. These values cannot be changed and your recordings will always take place at one of these sensitivity levels.

ENABLE A LUT.

To take full advantage of the Cine EI mode the next step is to enable a LUT for the viewfinder and also optionally for the HDMI and SDI outputs.

SDI-MLUT-ON_1.1.10-600x338 A Guide the the FX6's CineEI Mode.
MLUT’s are enabled and disabled via status page 5 or in the main menu under Shooting – LUT NO/OFF

 

The default LUT is Sony’s s709 LUT. This is the same LUT as used by the Venice digital cinema camera. s709 is designed to be a starting point for a film style look. To achieve this film style look it uses brightness levels more commonly found in feature films rather than the levels normally used in the majority of regular TV shows.

selected-lut-status-pages_1.1.1-600x338 A Guide the the FX6's CineEI Mode.
The default LUT is s709. The LUT can be changed from Status Page 5 or in the main menu under PAINT – BASE LOOK – SELECT


LUT EXPOSURE LEVELS

There are some important things to understand about different LUTs and Base Looks. Each LUT/Look will have it’s own optimum brightness levels. They will not all be the same. Some will be brighter or darker than others when exposed correctly, so it’s vital that you understand what levels any LUT that you chose to use needs to be exposed at.

Another LUT that the FX6 includes is Sony’s 709(800) LUT. This LUT is more closely aligned with the levels used in normal TV productions, so it looks very different to s709 and has very different brightness levels when exposed correctly.

The chart below gives the “correct” exposure values for S-Log3 as well as some guide values based on my own measurements for the s709 and 709(800) LUTs in the FX6.

  Middle Grey Average Skin Tones 90% Reflectivity white card (add 2-3% for white paper).
S-Log3 41% 48-52% 61%
s709 44-45% 57-62% 77-78%
709(800) 44-45% 65-70% 89%

MEASURING THE EXPOSURE.

There are many ways to measure your exposure when shooting using S-Log3 and LUT’s. You could choose to use a light meter, in which case the light meter would be set to match the EI (Exposure Index) value set in the camera. You can just look at the image in the viewfinder and judge when it looks right. Most of the time this is OK, but it isn’t particularly accurate. My prefered method is to use a white card or grey card and then use the cameras built in video signal monitor and the waveform display to actually measure the brightness of the grey card or white card.

Video-Signal-Monitor-ON_1.1.5-600x338 A Guide the the FX6's CineEI Mode.
The waveform display is enabled in the menu under MONITORING – DISPLAY ON/OFF – VIDEO SIGNAL MONITOR


If you are not familiar with a waveform display it actually really easy to understand. The bottom of the waveform is black and the very top is 109%, the brightest that the camera can ever record to. The left hand side is the left of the video image and the right is the right of the video image. The thin reference lines across the waveform display are at 0% (the darkest a video image should ever normally be), 25%, 50%, 75% and 100%.

waveform-2 A Guide the the FX6's CineEI Mode.
The levels shown by the FX6’s waveform display


In addition the FX6’s waveform display includes 2 yellow lines. The position of these yellow lines is determined to the levels that the cameras zebras are set to. By default the lower yellow line will be at 70% to match Zebra 1 and the upper line at 100% to match zebra 2.

waveform-1 A Guide the the FX6's CineEI Mode.

MEASURING THE EXPOSURE.

The waveform display measures the signal that is on the HDMI and the SDI output. So once you have turned on the LUT for the HDMI/SDI it is the levels of the LUT that is being measured. What the waveform is measuring is indicated just above the waveform display.

To make it easier to understand how CineEI works and to show you how I like to have my FX6 setup, I find it easier to start off by turning OFF the LUT for the SDI and HDMI and measuring the exposure of the S-Log3. If you do this when the the Exposure Index (EI) is equal to the Recording or Base ISO then we can establish the correct exposure for the S-Log3 using a white card or white piece of paper and then also check the exposure of the LUT.

FIRST CHECK AND SET THE EXPOSURE INDEX LEVELS.

With the cameras base ISO set to low / 800 ISO I recommend that you set the EI levels in the main menu SHOOTING – ISO/Gain/EI as follows: 

EI-Levels_1.1.13-600x338 A Guide the the FX6's CineEI Mode.
My recommended exposure index levels of 800/400/200 EI

 

ISO/GAIN BUTTON:

When using the CineEI mode you can change the EI several ways. The most commonly used ways will likely be via the L/M/H ISO/Gain switch or by pressing the ISO/Gain button and then using the multi-function dial (MFD) to change the EI.  Do note that when you use the multi-function dial or Direct Menu to change the EI this new EI setting changes the preset value associated with the current position of the L/M/H switch.

I do not set an Exposure Index higher than the base recording ISO. The reason for this is that if you record using a high EI value your images will be noisy and grainy and could be very difficult to grade. Because you don’t ever see your final results until you get into post production, if you accidentally record noisy log you won’t really know how bad the footage will be until it is perhaps too late to do anything about it. So I set the EI for the Low Base 800 ISO as H>800EI,  M>400EI, L>200EI. The difference between each of these EI’s is one stop and that makes it easier when you are checking any exposure changes. 

For the 12,800 High base ISO I set the EI to H>12800EI, M>6400EI, L>3200EI.

FOR THIS EXAMPLE START AT LOW BASE/800 ISO and 800 EI.

By using the same EI as the base recording ISO there will be no offset or difference between the correct exposure for the LUT and the correct, or base exposure for the S-Log3. Expose the LUT corrrectly and the S-Log3 will be also be normally exposed. Expose the S-Log3 normally and the LUT will look correct.

FOR THIS EXAMPLE LET’S START WITH THE SDI/HDMI LUT OFF.

For this example I am going to start with the LUT OFF for the SDI and HDMI, this way the waveform display will be measuring the S-Log3. Just above the waveform it should say SG3C/Slog3, telling you the waveform is measuring the S-Log3. 

MLUT-VF-Only_1.1.8-600x338 A Guide the the FX6's CineEI Mode.
When the LUT (MLUT) is off for the SDI/HDM the waveform will be measuring the S-Log3 exposure level.

 

Referring to the table of exposure levels above we can see that the correct S-Log3 exposure for a white card (90% reflectivity white) is 61% – if using a normal piece of printer paper I suggest using a value a little higher (around 63%) as white paper tends to be a little brighter than a proper white test card.

SETTING ZEBRA 1 TO 61%

To make finding where 61% is on the waveform I recommend setting Zebra 1 to 61% so that the lower of the two yellow zebra lines is at 61%.

zebra1-61-1_1.1.8-600x338 A Guide the the FX6's CineEI Mode.
Set Zebra 1 to 61% via the main menu and MONITORING – ZEBRA.


So now when checking the exposure of a white card when the waveform is measuring the S-Log3 it is simply a case of adjusting the exposure until the white card is at the same level as the 61% line. Alternately you could use an 18% grey card, in which case you would set Zebra 1 to 41%, however there are often times when I forget my grey card but I almost always have a piece of paper somewhere.

white-card-at-61 A Guide the the FX6's CineEI Mode.
White target exposed at 61% when measuring the S-Log3

 

So now we know the S-Log3 is correctly exposed lets turn ON the LUT for the SDI and HDMI outputs and check the exposure level of the s709 LUT.

TURN ON THE LUT.

SDI-MLUT-ON_1.1.10-600x338 A Guide the the FX6's CineEI Mode.
MLUT’s are enabled and disabled via status page 5 or in the main menu under Shooting – LUT NO/OFF

 

And if we refer to the exposure chart given towards the top of the page we will see that white for the s709 LUT is 77%. So now let’s set Zebra 2 to 77% to make 77% easier to find on the waveform. Do remember however that other LUTs may need different levels, 77% is just for s709, 709(800) would require Zebra 2 to be set to 89%.

SET ZEBRA 2 TO 77% FOR s709

zebra2-77-2_1.1.12-600x338 A Guide the the FX6's CineEI Mode.
Set Zebra 2 to the correct white level for the LUT you are using via the main menu and MONITORING – ZEBRA.

 

Now with the LUT ON for the SDI/HDMI we should see the brightness of the white card line up with the upper yellow line that represents Zebra 2 and 77%.

s709-LUT-correct-version-2 A Guide the the FX6's CineEI Mode.

 

s709-77pc-zebra_1.1.13-600x338 A Guide the the FX6's CineEI Mode.

As you can see from the above example when the Base ISO and Exposure Index are matched, when the LUT for the SDI/HDMI is OFF and the white card is at 61% on the waveform the S-Log3 is correctly exposed.

Then when the s709 LUT is ON for the SDI/HDMI and the white card is at 77% we are correctly exposed. By having Zebra 1 set at 61% (for S-Log3) and Zebra 2 set for the white level for for your chosen LUT we can check either simply by turning the HDMI/SDI LUT ON or OFF.

USING THE 709(800) LUT INSTEAD

If you want a more contrasty looking image in the viewfinder and similar brightness levels to other video cameras – for example skin tones around 70% you might prefer to use the 709(800) LUT.  When using the 709(800) LUT to measure a white card you should set Zebra 2 to 89%. It’s also worth noting that with the 709(800) LUT, if you wish, you could just leave the zebras at their default settings with Zebra 1 at 70% where just like a conventional Rec-709 video camera they will appear over brighter skin tones when viewing via the LUT. 

709800-correct A Guide the the FX6's CineEI Mode.

CHANGING THE EXPOSURE INDEX TO OFFSET THE LOG EXPOSURE.

Sometimes it can be desirable to expose the S-Log3 a little brighter. For example when shooting scenes with a low average brightness level or scenes with large areas of shadows. The FX6 has very low noise levels at 800 ISO base. So for most scenes with higher average brightness levels there is no need to expose the log brighter. But there is a bit more noise at 12,800 ISO base. As a result it can be beneficial to expose the S-Log3 a bit brighter when using 12,800 ISO base.

The CineEI mode makes this very easy to do in a very controlled manner. Keeping the amount of over exposure constant helps speed up the grading process as all your material can be graded in exactly the same way.

Over exposing or underexposing Log does not change the captured dynamic range, it will always be the same. However exposing log brighter will reduce the highlight range while at the same time increasing the shadow range. A brighter exposure will result in less noise after grading.

Exposing log darker will increase the highlight range but decrease the shadow range. A darker exposure will result in more noise after grading. Because under exposed log can become very noisy, very quickly I do not recommend under exposing log,  because of this I strongly advise against ever using an EI that is higher than the base ISO as this will result in under exposed log.

CHANGING THE EI ONLY CHANGES THE LUT.

When you change the Exposure Index the only thing that actually changes is the brightness of the LUT. So for EI to work you must be monitoring via a LUT.

Below is what happens to the image in the viewfinder when you have a LUT enabled (s709 in this case) and you lower the EI from 800 EI down to 200 EI in 1 stop steps and make no changes to the exposure.

s709-CORRECT2_1.1.24-600x338 A Guide the the FX6's CineEI Mode.
s709 at 800 EI and correctly exposed – note aperture is f8.
s709-400EI-2_1.1.23-600x338 A Guide the the FX6's CineEI Mode.
s709 with the EI set one stop lower at 400 EI but no change to the exposure made, aperture is still f8.
s709-200EI-2_1.1.24-600x338 A Guide the the FX6's CineEI Mode.
s709 now 2 stops darker at 200EI – no change to exposure, aperture is still f8

 

As we have not changed the exposure in any way, the only thing changing is the brightness of the LUT. The recording levels have not yet changed in any way.

BUT NOW WE CHANGE THE EXPOSURE

Because the image in the viewfinder is now dark and the white card no longer reaches the correct exposure for the LUT, we now adjust the exposure. In this example I simply opened the aperture by 2 stops from f8 to f4 to match the 2 stop change in the LUT brightness. Now the image in the viewfinder looks correct again and the white card is meeting the upper yellow line again (77% as set by Zebra 2 level).

s709-200EI-Corrected_1.1.25-600x338 A Guide the the FX6's CineEI Mode.
The EI is at 200 but now the aperture has been opened by 2 stops to f4 so now the LUT is exposed correctly again.

 

BECAUSE THE EXPOSURE IS BRIGHTER THE S-LOG3 IS NOW ALSO BRIGHTER.

Because I have opened the aperture by 2 stops to make the 200 EI LUT exposure look right the S-Log3 recordings will now be 2 stops brighter. If I turn off the LUT for the SDI/HDMI we can see that the S-Log3 is much brighter 2 stops brighter like this, the S-log3 white card level becomes 79%, so it appears slightly above the 77% Zebra 1 line.

s-log3-200ei-corrected_1.1.26-600x338 A Guide the the FX6's CineEI Mode.
After increasing the exposure by 2 stops to compensate for the 2 stop darker LUT (200EI) the S-Log3 recordings become 2 stops brighter and the S-Log3 white card level becomes approx 79%

 

Buy making the LUT darker by 2 stops, then adjusting the exposure upwards 2 stops to return the LUT to the original brightness we have made our recordings 2 stops brighter. This is how you use CineEI to alter the brightness of your recordings.

At Low base ISO (800 ISO) the FX6 is a low noise camera, so there is no need to routinely over expose the log as there is with more noisy cameras like the FS5 or FS7. So I normally shoot at 800 EI. When using the high base ISO or 12,800 ISO there is a bit more noise and when using high base I will typically set the EI to 6400 EI as the 1 stop brighter recordings that this will result in helps compensate for the increased recording noise.

In the examples given here I have used a white card to set the exposure. This is accurate and highly repeatable. But there will be times where you may not have a white card. At these times CineEI can still be used either by setting the Zebras to the appropriate skin tone levels for the chosen LUT (see the table towards the beginning) or by carefully “eyeballing” the brightness of the LUT image – if it looks right, it probably is right. If you are eyeballing it I highly recommend a deep sunshade or other device to exclude as much light as possible from the viewfinder.

CLIP PLAYBACK QUIRKS (YOU MUST ENSURE YOU HAVE UPDATED YOUR CAMERAS FIRMWARE as there was a bug in the initial release firmware that caused the playback EI to be applied back to front).

One great FX6 feature is that when you play back clips in the CineEI mode the camera can apply a LUT to the clip. Simply enable the LUT you want to use as you would when shooting. The FX6 applies then the EI offset that you have assigned to the L/M/H gain/ISO switch.

HOWEVER YOU DO THIS BE AWARE THAT THE L/M/H Gain switch alters the brightness of the clips when played back via a LUT. The only time there is no playback offset is when the switch is set to 800EI. So make sure you understand what EI it is you are looking at when playing back clips in CineEI as if you use the wrong EI your clips may appear over or under exposed.

Changing the way the camera looks and using LUTs in Custom Mode:

You can also use any user LUTs that you have loaded into the camera to alter the base look when you are shooting in custom mode. For more information on that please watch the video below.

New LUT – Chess

Here’s a new LUT for you, inspired by a the look of the Netfix show “the Queen’s Gambit. I’ve called the LUT “Chess”. It’s designed for use with S-Log3 and SGamut3.cine and I think it works really well with most Sony S-Log3 capable cameras including the FX6, FX9, FS7, FS5, F5 and F55 etc. As well as Sony’s video cameras it will also work with the A7SIII and other Sony Alpha cameras.

In the download you will find 2 LUTs. The 65x version is for post production and grading, the 33x version is for use as a camera LUT.  While I have aimed to replicate much of the look of the TV series it must be noted that grading is only a small part of the look. Set design, the colour of the sets and costume also play a significant roll.

s709-look-new_1.1.12-1024x576 New LUT - Chess
S-Log3 to s709 Standard look.
Chess-Look-new_1.1.11-1024x576 New LUT - Chess
S-Log3 to Chess Look LUT
s709-look-2_1.2.2-1024x576 New LUT - Chess
S-Log3 to s709
new-chess-look2_1.2.1-1024x576 New LUT - Chess
S-Log3 ro Chess look LUT

If you find this LUT useful please consider buying me a cocktail or other beverage. Thank you! It does take a while to develop these LUT’s and contributions are a good incentive for me to create more!


 

Your choice:


Click Here to Download the Chess LUT

 

You can use this LUT as a camera LUT or for grading. If you are using the Sony FX6 you can use this LUT in Custom Mode as a Base Look. For more information on how to do that please watch the video below.

 

Changing the FX6’s base look in Custom Mode using LUT’s

This is extremely cool! You can change the FX6’s base look in custom mode using LUTs. This is not the same as baking in a LUT in Cine EI as in custom mode you can change the gain or ISO just as you would with any other gamma. But there’s more than that – you can even adjust the look of the LUT by changing the detail settings, black level, matrix and multi-matrix. Watch the video to see how it’s done.


The LUT’s used in the video can be downloaded from here. http://www.xdcam-user.com/2014/11/new-film-look-luts-for-the-pxw-fs7-pmw-f5-and-pmw-f55/

Or from here: https://pro.sony/en_SC/technology/alister-chapman-blockbuster-lut-v2

Making Sony Log Cameras Behave Like Arri Cameras When Shooting Cine EI and S-Log3.

Arri have a little trick in their cameras when shooting log to ProRes that the Sony Log cameras don’t have. When you change the Exposure Index in an Arri camera they modify the position of the exposure mid point and the shape of the Log-C gamma curve. There is actually a different Log-C curve for each EI. When you take this into post it has the benefit that the brightness at each EI will appear similar. But as the curve changes for each EI a different LUT is needed for each exposure if you want something shot at say 800EI to look the same as something shot at 200EI.

With a Sony camera the same S-Log curve is used for each Exposure Index and the LUT brightness is changed so that you end up altering the mid point of the recording as well as the highlight and shadow range. In post each EI will appear to be a different brightness. You can use the same LUT for each EI provided you do an exposure correction prior to adding the LUT or you can use dedicated offset LUT’s for each exposure.

But what you need to remember is that you are always working within a restricted recording range with either system. You can’t go darker than the black recording level or brighter than the highest value the codec can record.

If you do it in camera, as Arri do and change the log curve, at a low EI you seriously constrict the recording range (at 200 EI peak only reaches around 78IRE). This happens because at a low EI you put more light on to the sensor. So to keep the mid range looking a normal brightness in post it must be recorded at at a level that is offset downwards compared to normal. So with all the levels now offset downwards to compensate for the brighter exposure you end up recording your entire capture range with a reduced or compressed recording range. In addition to avoid clipping the blacks at a low EI the shadows are rolled off so you lose some detail and textures in the shadows. You can see the different Log-C curves in this Arri White paper.

Most people choose a low EI for 2 reasons, better signal to noise ratio and improved shadow range. The Arri method gives you the better SNR but while the dynamic range is preserved it’s recorded using less data and in particular the shadow data decreases compared to shooting at the base ISO.

Shoot at a high EI, you put less light on to the sensor. So to maintain similar looking mids in post everything has to be recorded at a higher level. Now you have a problem because the highlights will extend beyond the upper limits of the recording range so  Arri have to add a highlight roll off at the top of the Log-C curve. This can present some grading challenges as the curve is now very different to regular Log-C. In addition the highlights are compressed.

Most people choose to shoot at a high EI to extend the highlight range or to work in lower light levels.

The latter is a bit of a pointless exercise with any log camera as the camera sensitivity isn’t actually any different, you are only fooling yourself into thinking it’s is more sensitive and this can result in noisy footage. If you using a high EI to extend the highlight range then really the last thing you want is the extra highlight roll off that Arri have to add at 3200 EI to fit everything in.

One thing here in Arri’s favour is that they can record 12 bit ProRes 444. 12 bits helps mitigate the compressed recording range of low EI’s provided the post workflow is managed correctly.

The beauty of the Sony method is the recording range never changes, so low EI’s and brighter recordings deliver better shadow ranges with more data in the shadows and mids and high EI’s with darker recordings deliver better highlight ranges with no additional data restrictions or additional roll-offs giving the cinematographer more control to choose the exposure mid point without compromise to the data at either end.

But it does mean that post need to be awake and that the shooter needs to communicate with post regarding the brighter/darker looking images. But to be honest if post don’t understand this and recognise what you have done either buy just looking at the footage or checking the metadata what chance is there of post actually doing a decent job of grading your content? This should be fundamental and basic stuff for a colourist/grader. For a colourist/grader to not understand this and how to work with this is like hiring a camera operator that doesn’t know what an ND filter is.

The Sony FS7/FX9/F5/F55/Venice cameras can do something similar to an Arri camera by baking in the S-Log3 LUT. Then in post the exposure will look the same at every EI. BUT you will lose some highlight range at a low EI’s and some shadow range at a high EI’s without gaining any extra range at the opposite end. As a result the total dynamic range does  reduce as you move away from the base ISO.

In addition on the Venice, FS7/F5/F55 (and I suspect in a future update the FX9) you can bake in a user LUT to the SxS recordings. If you  create a set of S-Log3 to S-Log3 LUT’s with EI offsets included in the LUT you could replicate what Arri do by having an offset and tweaked S-Log3 User LUT for each EI that you want to shoot at. You would not use the cameras EI control you would leave the camera st the base ISO. The LUT’s themselves will include the exposure offset. These will maintain the full dynamic range but just like Arri they will  need to roll off the shadows or highlights within the LUT.

But monitoring will be tricky as you won’t have the benefit of a 709 type LUT for monitoring so you you may need to use an external monitor or viewfinder that can apply a LUT to it’s image. The good news is the same LUT would be used in the monitor for every version on the offset S-Log3 LUT that you are baking in as the exposure brightness levels will be the same for each offset.

So here you are a set of 4 S-Log3/S-Gamut3.cine offset LUT’s for those Sony cameras that will take a user LUT. I have named the LUT’s – 2S Down SL3C, 1S Down SL3C,  1S UP SL3C, 2S UP SL3C.

The name means (Number of Stops) (Down or Up) (Slog3.Cine).

So if the cameras base ISO is 2000 (F5/FS7 etc) and you want to shoot at the equivalent of 1000EI, which is 1 stop down from base you would use “1S Down SL3C”.

As always (to date at least) I offer these as a free download available by clicking on the links below.  But I always appreciate a contribution if you find them useful and make use of them. I will let you pay what you feel is fair, all contributions are greatly appreciated and it really does help keep this website up and running. If you can’t afford to pay, then just download the LUT’s and enjoy using them. If in the future you should choose to use them on a paying project, please remember where you got them and come back and make a contribution. More contributions means more LUT offerings in the future.

Please feel free to share a link to this page if you wish to share these LUT’s with anyone else or anywhere else. But it’s not OK to to share or host these on other web sites etc.

Here’s the link to download my offset S-Log3 Camera LUTs

To make a contribution please use the drop down menu here, there are several contribution levels to choose from.


Your choice:



pixel Making Sony Log Cameras Behave Like Arri Cameras When Shooting Cine EI and S-Log3.

Are LUT’s Killing Creativity And Eroding Skills?

I see this all the time “which LUT should I use to get this look” or “I like that, which LUT did you use”. Don’t get me wrong, I use LUT’s and they are a very useful tool, but the now almost default reversion to adding a LUT to log and raw material is killing creativity.

In my distant past I worked in and helped run  a very well known post production facilities company. There were two high end editing and grading suites and many of the clients came to us because we could work to the highest standards of the day and from the clients description create the look they wanted with  the controls on the equipment we had. This was a digibeta tape to tape facility that also had a Matrox Digisuite and some other tools, but nothing like what can be done with the free version of DaVinci Resolve today.

But the thing is we didn’t have LUT’s. We had knobs, dials and switches. We had to understand how to use the tools that we had to get to where the client wanted to be. As a result every project would have a unique look.

Today the software available to us is incredibly powerful and a tiny fraction of the cost of the gear we had back then. What you can do in post today is almost limitless. Cameras are better than ever, so there is no excuse for not being able to create all kinds of different looks across your projects or even within a single project to create different moods for different scenes. But sadly that’s not what is happening.

You have to ask why? Why does every YouTube short look like every other one? A big part is automated workflows, for example FCPX that automatically applies a default LUT to log footage. Another is the belief that LUT’s are how you grade, and then everyone using the same few LUT’s on everything they shoot.

This creates two issues.

1: Everything looks the same – BORING!!!!

2: People are not learning how to grade and don’t understand how to work with colour and contrast – because it’s easier to “slap on a LUT”.

How many of the “slap on a LUT’ clan realise that LUT’s are camera and exposure specific, how many realise that LUT’s can introduce banding and other image artefacts into footage that might otherwise be pristine?

If LUT’s didn’t exist people would have to learn how to grade. And when I say “grade” I don’t mean a few tweaks to the contrast, brightness and colour wheels. I mean taking individual hues and tones and changing them in isolation. For example separating skin tones from the rest of the scene so they can be made to look one way while the rest of the scene is treated differently. People would need to learn how to create colour contrast as well as brightness contrast. How to make highlights roll off in a pleasing way, all those things that go into creating great looking images from log or raw footage.

Then, perhaps, because people are doing their own grading they would start to better understand colour, gamma, contrast etc, etc. Most importantly because the look created will be their look, from scratch, it would be unique. Different projects from different people would actually look different again instead of each being a clone of someone else’s work.

LUT’s are a useful tool, especially on set for an approximation of how something could look. But in post production they restrict creativity and many people have no idea of how to grade and how they can manipulate their material.

New s709 LUT For The FX6 and FX9 That’s Less Green Than The Sony LUT.

Many users of the FX9 that have been shooting S-Log3 are finding that when they add the standard Sony version of the s709 LUT that their pictures have a slight green tint. I believe that this is because originally the s709 LUT was designed for the Sony Venice camera and the FX9 is very slightly different.  I recently created an experimental LUT to minimise this tint but some people found this tended to push some images slightly magenta.

So I now have a new version of the LUT which really does help combat the green tint. The difference between this LUT and Sony’s original s709 LUT is very small. The idea isn’t to create a new look, just to help get rid of the tint. So you won’t see a big difference, it’s subtle, but I think it really is better.

Click Here to download the ACs709 For FX9 LUT set.

Note: These LUTs are for S-Log3 and SGamut3.cine from the FX9. As usual I have include different versions of the LUT. There are 65x LUT’s suitable for grading as well as 33x LUT’s for monitors or grading software that doesn’t support the higher quality 65x LUTs. There are also minus1 and minus2 LUTS that have 1 and 2 stop exposure shifts for footage that has been shot brighter than the base exposure. In addition I have include the same LUTs but with Legal range input levels for use on Atomos and other recorders that record ProRes in using Legal Range.

Please feel free to share a link to this page if you wish to share these LUT’s with anyone else or anywhere else. But only share via a link to this page please.

If you find these LUT’s useful please consider buying me a coffee or other drink. To make a contribution please use the drop down menu here, there are several contribution levels to choose from.


Your choice:



pixel New s709 LUT For The FX6 and FX9 That's Less Green Than The Sony LUT.

S709 LUT (Venice Look) And 709(800) For LEGAL RANGE PRORES S-Log3 On Atomos and other Recorders.

As noted in my previous post there can be some issues with the way ProRes is recorded on many external monitors as a legal range files rather than Data Range.

Another side effect of this is that LUT’s designed for post production as well as most camera LUT’s don’t work correctly in the monitor. So even when you apply the same LUT in the camera as in the monitor the images look different.

To address this I am providing here 2 sets of LUTs for S-Log3 and SGamut3.cine designed to match the built in s709 and 709(800) Luts included in many Sony cameras. These LUTs are specifically for external recorders and should not be used in camera. When you use these LUT’s the pictures on the monitor should now match the the images in the cameras viewfinder when the built in  LUT has been applied.

You will find 3 LUTs of each type. One for the base exposure, one for footage exposed 1 stop brighter (minus1) and one for footage exposed 2 stops brighter than base (minus2).

As always (to date at least) I offer these as a free download available by clicking on the links below. Try them before you decide then pay what you feel is fair. All contributions are greatly appreciated and it really does help keep this website up and running. If you can’t afford to pay, then just download the LUT’s and enjoy using them, tell your friends and send them here. If in the future you should choose to use them on a paying project, please remember where you got them and come back and make a contribution. More contributions means more LUT offerings in the future.

Click Here to download the 709(800) and S709 Legal In LUTS for external recorders.

If you want to share the LUT’s please do so by a link to this page. You may not sell or distribute these LUTs anywhere without my prior consent.

To make a contribution please use the drop down menu here, there are several contribution levels to choose from.


Your choice:



pixel S709 LUT (Venice Look) And 709(800) For LEGAL RANGE PRORES S-Log3 On Atomos and other Recorders.

Experimental s709 LUT Specifically for the FX9.

I’ve had a few people comment that they feel that the PXW-FX9 is a touch green when you shoot S-Log3 and SGamut3.cine and then add the standard Sony s709 V200 LUT in post. So I have created a slightly modified version of the s709 LUT that I have tweaked specifically for the FX9. You can download it using the like below. Do let me know what you think.

AC-s709-for-fx9_v1.2_experimental.cube