Colour correction for beginners?

[Serums]

I'm looking at starting my first video project, after previously working with audio and subtitles (a friend did the earlier reconstruction I was planning on).

I'm aiming to colour correct the new HD version of a film. I've got an earlier upscaled fan project that I was planning to use for reference, unless there's something closer to the theatrical colours. 

I'm curious if there's beginner-friendly software that'll try to match the colours from the fan project to the new version (colours of the new version are too yellow), and allow me to correct the result as closely as possible? I've got Davinci Resolve and DrDre's Color Match v1.2, but I'm happy to try other software. 

Thanks.

[deleted user]

Go ahead and try DrDre's tool, it's very good. (Assuming you haven't played with it yet)

[Serums]

Go ahead and try DrDre's tool, it's very good. (Assuming you haven't played with it yet)

Thanks for that. I've played with it, for a clip that's a few minutes long. But could it work with bigger chunks of a film?

[deleted user]

I'm not aware of it working on videos, just on still images. You have to let it create the LUT between two images and then apply it to a video. Of course you can make a collage of many images and use that so that it has more material to work with. I do it like that regularly. But either way, if the two videos you're trying to match have completely different gradings from shot to shot, you will only get an approximate match overall best case or worst case, the result will be completely unusable. So it depends on how much you're willing to accept that not every single scene is gonna match perfectly. If you cannot accept that, you have to do the matching shot by shot. A milder version of that approach would be to create a set of LUTs that cover most scenes well-enough and then manually apply the best fitting LUT to each scene. That would be a bit similar to what I did with my Shaun of the Dead regrade, though obviously in that case a lot of it came down to creative decisions about which part would work best with which colors.

Edit: What you could do with that simplified approach, for example, would be to create thumbnails for the entire movie and overlay them with your reference and then flick between the two thumbnail views and if you have a little intuition, you will be able to tell which scenes/segments will not be "compatible" with others and thus you could kind of put them into different groups. Simple example: If you switch between source A and source B, thumbnail 1-3 could be darker in source A, but thumbnail 4 could be darker in source B. Obviously a LUT cannot account for both; a LUT can make an image brighter or it can make it darker, it can't do both. So you could group the scenes roughly into "brighter in source A" and "brighter in source B" and thus you would be able to get more consistent results. Similar for colors. For example if one scene is much greener in source A but another is much greener in source B, you are unlikely to get a consistent match unless you group them similarly.

[Booshman]

I've been using DrDre's for a while and I hadn't thought of using it like this. Sounds like a good technique.

[Serums]

I'm not aware of it working on videos, just on still images. You have to let it create the LUT between two images and then apply it to a video. Of course you can make a collage of many images and use that so that it has more material to work with. I do it like that regularly. But either way, if the two videos you're trying to match have completely different gradings from shot to shot, you will only get an approximate match overall best case or worst case, the result will be completely unusable. So it depends on how much you're willing to accept that not every single scene is gonna match perfectly. If you cannot accept that, you have to do the matching shot by shot. A milder version of that approach would be to create a set of LUTs that cover most scenes well-enough and then manually apply the best fitting LUT to each scene. That would be a bit similar to what I did with my Shaun of the Dead regrade, though obviously in that case a lot of it came down to creative decisions about which part would work best with which colors.

Edit: What you could do with that simplified approach, for example, would be to create thumbnails for the entire movie and overlay them with your reference and then flick between the two thumbnail views and if you have a little intuition, you will be able to tell which scenes/segments will not be "compatible" with others and thus you could kind of put them into different groups. Simple example: If you switch between source A and source B, thumbnail 1-3 could be darker in source A, but thumbnail 4 could be darker in source B. Obviously a LUT cannot account for both; a LUT can make an image brighter or it can make it darker, it can't do both. So you could group the scenes roughly into "brighter in source A" and "brighter in source B" and thus you would be able to get more consistent results. Similar for colors. For example if one scene is much greener in source A but another is much greener in source B, you are unlikely to get a consistent match unless you group them similarly.

Thanks for the in-depth explanation! I can't wait for the project source to get here, to test this out. Hmm, I could potentially test out the possible results now. I've got the colour source handy, and I know there are a few screencaps of the new version online. If the dimensions match up, I need not wait to make a start on it.

[Colek]

You can use Photoshop's auto-align feature to match two sources for using with DrDre's tool.

[Serums]

Excellent, thanks for that. I've been using Avidemux to isolate scenes to match with the screenshots. Tested a few with drdre's tool, and so far the results are good. Can't do much more until the blu-ray arrives, but it should make a good start.