35mm photo film emulation - LUT design

[TrueIndigo]

Here is the image with just simple colour correction (colour wheels) to improve the image and then applying the LUT (ie. the filters used in that order), along with the resulting RGB parade.

[TrueIndigo]

Here are some 100% scale details from this frame.

[webrunner5]

WoW is all I can say. I guess I will take back my original criticisms since I have seen more evidence. Well done.

[hyalinejim]

4 hours ago, TrueIndigo said:

Here are some 100% scale details from this frame

Skin looks good! What do you think about the level of contrast?

 

3 hours ago, webrunner5 said:

WoW is all I can say

Thanks for that @webrunner5 If you still have your GH5 or some old VLog files lying around maybe you could give it a whirl on your own footage and check it out in more detail. 

 

Also, I meant to ask @kye if you have access to any downloadable VLog would you mind having a look? Your opinion on the contrast level would be really valuable. Or I could send you some frames to mess around with.

[kye]

8 hours ago, hyalinejim said:

Also, I meant to ask @kye if you have access to any downloadable VLog would you mind having a look? Your opinion on the contrast level would be really valuable. Or I could send you some frames to mess around with.

Yeah, send me a few frames - happy to have a play.

[TrueIndigo]

Webrunner5 - thanks for the comment, it was hyalinejim's LUT which did the heavy lifting on that image.

Hyalinejim - Skin tones in this example were pleasing and accurate. I would say my dad's actual skin tone is highly similar to what you see here. For this particular image I actually increased the contrast a bit with colour correction, but I did not have much to do - your LUT nicely produced the image by itself. I arranged some coloured objects in the background as a crude colour chart and it's nice to see the coffee jar top rendering as a good red instead of orangey. Thank you for your big effort.

Didn't keep many details of this test but it was: UHD, 25p, 10-bit, VLOG-L, 400 ISO, custom white balance from a grey card. Daylight interior with the subject lit by a single LED panel. Can't remember the exact lens but it would have been one of my vintage Nikon primes (AIS series).

I know it's easy for me to say (because it must take a lot of work), but is it possible to make a version of your LUT for the HLG profile so that more people can use it?

[kye]

13 minutes ago, TrueIndigo said:

Webrunner5 - thanks for the comment, it was hyalinejim's LUT which did the heavy lifting on that image.

Hyalinejim - Skin tones in this example were pleasing and accurate. I would say my dad's actual skin tone is highly similar to what you see here. For this particular image I actually increased the contrast a bit with colour correction, but I did not have much to do - your LUT nicely produced the image by itself. I arranged some coloured objects in the background as a crude colour chart and it's nice to see the coffee jar top rendering as a good red instead of orangey. Thank you for your big effort.

Didn't keep many details of this test but it was: UHD, 25p, 10-bit, VLOG-L, 400 ISO, custom white balance from a grey card. Daylight interior with the subject lit by a single LED panel. Can't remember the exact lens but it would have been one of my vintage Nikon primes (AIS series).

I know it's easy for me to say (because it must take a lot of work), but is it possible to make a version of your LUT for the HLG profile so that more people can use it?

The HLG profile isn't exactly a standard (I've tested it) but it's relatively close to Rec2100 so you could try converting from that to V-Log and try the LUT on that.  @hyalinejim might clarify the exact settings for that, but if you have a moment you could potentially try?

[hyalinejim]

12 hours ago, TrueIndigo said:

Skin tones in this example were pleasing and accurate

 

12 hours ago, TrueIndigo said:

it's nice to see the coffee jar top rendering as a good red instead of orangey

It's worth pointing out that there's no guarantee that the skintones and reds are accurate to what they are in reality, although they may be. I've long been a believer in colour that is better than, rather than faithful to, reality. However, the LUT gives colours that are faithful to a particular film stock, exposed and digitised in a specific way. And it may well be the case that skin and reds are quite close in hue to how they are in reality. But blues, to give another example, are considerably "off", such that skies will be rendered as very slightly but noticeably more towards green rather than purple. So perhaps the blue of the bottle or your father's clothing look a bit different to reality.

 

In the LUT the hue, saturation and lightness of various colours will vary with respect to their colorimetric values in reality. And the relationship is not constant through the tonal range. Shadows, for example, are relatively saturated and highlights much less so. A lot of the skintones in this image are in the lower midtones and that gives the skin its robust colouration in this instance.

I suppose part of the reason for this variance between realistic colour and filmic colour is simply because of the way negative film inherently works as a recording material. But another part of it is by design: conscious decisions that the engineers at Kodak made to design a film with specific responses. 

I think most people agree that, broadly speaking, the colour of film is beautiful. I certainly do, and that's why I'm going for it!

12 hours ago, TrueIndigo said:

is it possible to make a version of your LUT for the HLG profile so that more people can use it?

It certainly is and, as @kye suggests, one way is to create a HLG to VLog transform. But as well as the curve, I'd assume the colour is different too. Another way is to create a LUT from scratch using a HLG chart shot. That would probably be more accurate. I don't have any plans to do that at the moment, though. I would have thought the vast majority shoot in VLog with only a handful of HLG crew? But I guess on the GH5 HLG gave many of the benefits of VLog without the added expense of the paid firmware update.