grading red footage

[Nick Shaw]

ps:is your lut only applied as viewing Lut while grading , than baked IN at the end?

If you are viewing on a Rec.709 monitor, and delivering for Rec.709 display you bake in the LUT. Same for e.g. P3. If your grading monitor does not match the final viewing environment, then it gets more complex, as you need to build a LUT to emulate that while grading, which you do not bake in.

 

[Gabriele Turchi]

If you are viewing on a Rec.709 monitor, and delivering for Rec.709 display you bake in the LUT. Same for e.g. P3. If your grading monitor does not match the final viewing environment, then it gets more complex, as you need to build a LUT to emulate that while grading, which you do not bake in.

i do have a 3D that match my Panasonic 12th gen 58" (as well as dream color) to 709 (lightspace CMS) , so i guess i will apply i viewing Lut (RG or RG2 (i have to build them ) on resolve as viewing , than bake in that LUT ...(hope i get it right...)

g

 

[Graeme Nattress]

Graeme, could please elaborate a bit on the usage of camera RGB ?
sometimes seems to me that does have nicer skin tone , but what i do notice is a less color separation on the elements of the image (let say compared to RC2) + HUE changes ...what is Camera RGB mean to be used for ? is the gamut larger than 709 ? so is not recommended for 709 color work ?

I'd not recommend the use of cameraRGB - it's un-calibrated, which is why the low colour separation you notice and some of the hues are "off" - red being very orange for instance. It's in the software for historical reasons, so that's why I'd suggest RC2. As for the colour of skin, I always tend to find RC2 superior.

Graeme

 

[Gabriele Turchi]

Nick : just tried ,
redlogfilm and Log-to-video lot as display lot on top ,
....but

for me is a bit shocking that when i use the keyer , davinci is picking the colors from the washed out image instead from the nice contrasty image i am seeing in my monitor (because of the Lut ) ...how you deal with this ? you and all the colorists that have done this for ages working with cineon log + print emulation Lut ....

what system you use ?

g

 

[Gabriele Turchi]

If you do want to use ACES, and I'd recommend you don't as it's buggy (not the RED implementation of the colour space, but the Academy's rendering process) get REDCine-X to export a EXR with the ACES space.

Graeme

hi graeme ,
how this ACES technically work ?
i was under the impression that rendered out .EXR linear light gamma in ACES color spaces ... but i tried today and when i opened the .EXR in davinci using the aces engine (new in resolve 8.1 (beta testing) the image is super contrasty overexposed and quite not right ...but moving the lift gamma gain controls seems that there is all the info in It though )i was able to restore the all image ) but the starting point was quite off ...

so when i render ACES EXR in RCX PRO , does is matter the ISO setting ? white balance ? gamma curve ?

Thanks
g

 

[M Most]

hi graeme ,
how this ACES technically work ?
i was under the impression that rendered out .EXR linear light gamma in ACES color spaces ... but i tried today and when i opened the .EXR in davinci using the aces engine (new in resolve 8.1 (beta testing) the image is super contrasty overexposed and quite not right ...but moving the lift gamma gain controls seems that there is all the info in It though )i was able to restore the all image ) but the starting point was quite off ...

so when i render ACES EXR in RCX PRO , does is matter the ISO setting ? white balance ? gamma curve ?

Thanks
g

Did you select the proper output transform (in your case, most likely Rec709)?

 

[Graeme Nattress]

Gabriele, ACES is just a colour space like REC709, Adobe1998, CIE XYZ or sRGB. There's nothing more magical to it than that. I don't know what Davinci is doing to get things into that colour space. In RCX the output for EXR is always linear to light with no tonal adjustments applied, but we do honour ISO/FLUT/Exposure to allow you to set rendering intent.

Graeme

 

[Gabriele Turchi]

Did you select the proper output transform (in your case, most likely Rec709)?

Thanks Mike ,
that actually helped a Lot ,
it seems that the image is read as Linear Gamma 1.0 in Aces Mode , so that Rec709 Lut helps , but it's sooo heavily saturated right ?

in Davinci seism that using the ACES and RED , the image is read at Linear Light , using the ISO and WB on the metadata + the ACES color spaces off course .
i really like the response of lift gamma and gain working on ACES ...but there are many things that works weird ....

mike , did you messed with it ?

g

 

[M Most]

Thanks Mike ,
that actually helped a Lot ,
it seems that the image is read as Linear Gamma 1.0 in Aces Mode , so that Rec709 Lut helps , but it's sooo heavily saturated right ?

No, not if you set it up right. I said specifically Output Transform, not a LUT. Unless you have a beta of Resolve 8.1 you don't have that available, and you don't have ACES color processing available either. If you are using 8.1, you will find the Input Transform and Output Transform pulldown menus at the bottom of the LUT section on the LUT page. If you are using R3d files directly, you set the Red settings to Linear Light and Redcolor 2, the input device transform to Red, and the output device transform to Rec709 for a
normal video monitor. If you use files converted by Redcine X in the manner described by Graeme, the Red settings have already been taken care of, but you still need to use the input and output device transforms for proper ACES processing. The initial results should be visually similar to what you'd obtain using Redgamma2 and Redcolor2, but with a bit more flexibility and arguably better flesh tones. If that's not what you're getting, you're either not using an 8.1 beta, or you haven't set it up correctly.

 

[RivaiC]

Mike, i thought you are not supposed to talk about ACES yet

 

[Gabriele Turchi]

No, not if you set it up right. I said specifically Output Transform, not a LUT. Unless you have a beta of Resolve 8.1 you don't have that available, and you don't have ACES color processing available either. If you are using 8.1, you will find the Input Transform and Output Transform pulldown menus at the bottom of the LUT section on the LUT page. If you are using R3d files directly, you set the Red settings to Linear Light and Redcolor 2, the input device transform to Red, and the output device transform to Rec709 for a
normal video monitor. If you use files converted by Redcine X in the manner described by Graeme, the Red settings have already been taken care of, but you still need to use the input and output device transforms for proper ACES processing. The initial results should be visually similar to what you'd obtain using Redgamma2 and Redcolor2, but with a bit more flexibility and arguably better flesh tones. If that's not what you're getting, you're either not using an 8.1 beta, or you haven't set it up correctly.

Thanks Mike

off course i have 8.1 beta (that i think went official today) , i think my mistake was not to set linear light on RED red page , so when i used the input Lut transform , was using red gamma 2 and everything got screwed ...so thanks for the tip ,

thanks

g

 

[Gabriele Turchi]

ps: buta actually i tried also to export .EXR from RCX using ACES spaces ..and even with those EXR , in Resove 8.1b , setting the input transform for Red gave me a super super bright image ... maybe there is a little but and in Red page need to be setup anyway to linear light ?
i wil test everything again in few hours.

g

 

[Brad Hawkins]

ps: buta actually i tried also to export .EXR from RCX using ACES spaces ..and even with those EXR , in Resove 8.1b , setting the input transform for Red gave me a super super bright image ... maybe there is a little but and in Red page need to be setup anyway to linear light ?
i wil test everything again in few hours.

g

Did you ever have any luck figuring out the proper settings?

From my tests, either with EXR (from RCX with ACES selected) or working directly with R3Ds (RC2/Linear) both provide a super bright (blown out) image when selecting RED input transform. Of course the data is still there and it is correctable, but obviously its not a good starting point.

 

[Gabriele Turchi]

no ...same results ,
but actually even worse ...
trying ACES on various shots is have realized how those 2 transform luts ,
does clip my highlight that I was not able to recover ...
also I noticed a lot of noise/banding (and I had just a primary correction going on ...)

g

 

[Brad Hawkins]

Hmm, might be an error on Davinci's part in RED Input Transform then. Oh well, ACES is still in development, so I'm sure it'll all get sorted out eventually. Just thought it would be fun to try it out. : )

 

[Nick Shaw]

Worth noting that (last time I checked) the EXR output of REDcine-X Pro appears not to use the correct ACES colour space when you choose the "use ACES" option, whereas the standard REDcine-X does. REDcine-X Pro appears to use REDcolor2.

 

[Gabriele Turchi]

mmm...I will double cel on this ...I think what I got from RCXPro was a linear light looking EXR (but problem is that when I use the RED input transform LUT and 709 output LUT in resolve the image gets way too bright and I realize that the top highlight are gone "forever " as well as having some color noise /banding ...but aside for this 2 issue I like the ACES responsiveness of the resolve tool in that mode ...


nick to use resolve ?

 

[Nick Shaw]

I do not have Resolve, but I have built myself an ACES based pipeline in Nuke. This gives a correct looking result with EXRs from RCX 501, but not with EXRs from RCX Pro b3.

 

[Gabriele Turchi]

thanks nick ,

may i ask if in Nuke working in ACeS is ok?
any issue ? (if you get the EXR right off course ..)

does nuke have the input transform LUT (for the camera used (red alexa etc..)and output transform LUT (709 ,P3 rtc..)when working in Aces ?
(wondering if the problem in resolve with Aces are related to a resolve issue or to ACES transform engine that is "buggy"..,

thanks

 

[Nick Shaw]

Nuke does not have built in ACES support. I built the transforms myself. Nuke always works in linear light, so fitting it to an ACES pipeline is relatively straightforward.