DrDre

The predicted colors are actually pretty close to the colors of a Technicolor print, which is also pretty dark for this scene.

Bluray matched to Tech IB print:

Automatic color retrieval for -1 LPP:

Sure, you could assume some optimal gamma curve. However, in practise it would probably be a matter of taste, and depend on the type of scene you’re color correcting.

Yes, the algorithm increases the range of the colors to span the maximum range from 0-255, but it doesn’t adjust the contrast or perform a gamma correction. That would be a post-processing step.

O yes, it’seems a matter of seconds…

Here’s an example of what Team Negative1’s Silver Screen Edition would look like using the automated film color retrieval algorithm (top raw LPP, bottom color correction). The sequence was corrected as a whole, so not each frame individually.

Thanks to all of you! I use MATLAB. I’m planning to make the algorithm part of a future release of the ColorCorrect tool.

Here’s a comparison between the results of the automated color correction algorithm for the ROTJ LPP, and the ROTJ Grindhouse, that features Harmy’s manual color correction. To make things clear, there’s no manual adjustmens in my corrections.

LPP:

Grindhouse:

DrDre:

LPP:

Grindhouse:

DrDre:

LPP:

Grindhouse:

DrDre:

Here’s a video example, using the badly faded 70 mm TESB sample posted by -1 a while ago.

Original:

https://drive.google.com/file/d/0B8_LYKyZDiajWFIwNU9UcFJqRG8/view?usp=sharing

Automated correction:

https://drive.google.com/file/d/0B8_LYKyZDiajOFg2aklhUlA4RG8/view?usp=sharing

Mavimao said:

Wow! How does this even work??

Short summary:

• Convert RGB space to CMYK space (color space for film)
• Align color channels by maximizing color channel correlation

guiser said:

That last shot of the Emperor looks too warm with possibly a yellow/orange cast to it. I’m not on my color managed display, but all the other images looked really nice, except that last one stood out to me.

That shot has a delibirate blue cast, while the algorithm neutralized the colors. This is why it is probably better to correct multiple shots simultaneously.

camroncamera said:

DrDre, I don’t think I’ve read you mentioning it… have you heard of the Digital ROC color-restoration processing plug-in by Kodak subsidiary Applied Science Fiction?
http://www.asf.com/products/plugins/rocpro/pluginROCPRO/
I don’t know that the product has been updated for many years. My Nikon film scanner came bundled with a version, but it only works during the scanning of film. Worked fairly well. Reminds me of your work on restoring color to red-faded motion picture film scans.

I’ve never heard of it, but there are probably many similarities.

It also appears Tarkin’s hair has more brown, than we thought…

It also appears those Death Star elevator walls have no green in them, as Mike Verta said.

towne32 said:

DrDre said:

towne32 said:

Wow, that looks really great.

For the faded Eastman prints, can you apply those settings to the entire reel and get as good of results?

That’s another question that needs answering.

Can you do similar tests on the (amazing vanishing) ESB Grindhouse release? Or is there not enough recoverable color information?

I’m on the road, but I will try to run some tests, when I get the chance. The Grindhouse should be easy compared to the red shifted TESB examples I posted.

I think we now know the Death Star conference room walls have a very slight blue cast, while the chairs are gray, and we have the color of Tarkin’s clothes.

towne32 said:

Wow, that looks really great.

For the faded Eastman prints, can you apply those settings to the entire reel and get as good of results?

That’s another question that needs answering.

CatBus said:

Does it deal well with filtered shots? i.e. the R2 canyon scene, which has an overall reddish cast over the whole thing, because it was filtered after it was shot. If so, how can you tell the difference between pink shift and red filter, or do you use neighboring frames somehow to see that this section is supposed to be redder than the others?

That´s something I´m still figuring out 😃.

This thread is about reconstructing the colors of the original Star Wars trilogy, specifically the first Star Wars and The Empire Strikes Back. To this end I developed an algorithm to retrieve the colors of faded color prints without using a color reference, in an objective manner, and therefore unaffected by subjective opinions of what the films should look like. The theatrical colors of the original unaltered Star Wars trilogy are used as the central theme of this thread, as these are heavily debated, and in the case of The Empire Strikes back are virtually unknown, since most 35mm and 70mm prints of the era have faded. For Star Wars the only unfaded 35mm references are the surviving Technicolor prints, but their accuracy as a color reference for the average 35mm print of Star Wars that was projected in 1977 in theatres around the world is debatable.

As a demonstration of the algorithm’s capabilities, I corrected the uncorrected scan of a low fade print done by Team Negative1 for their Silver Screen Edition with the algorithm. I applied a global correction to the entire reel, without manual adjustments. Although a gamma correction is in order, and many shots can use some additional tweaking, I think the results give a pretty clear impression of the colors of the original 1977 Star Wars.

Here’s the video sample that showcase the reconstructed colors:

https://drive.google.com/file/d/0B8_LYKyZDiajZzByMFdrUjhNVHc/view?usp=sharing

This comparison shows the state of the print scan before and after the color reconstruction:

…and here are some additional screenshots:

================================================================================================

Original start of the thread:

For a while now I’ve been working on figuring out an algorithm, that will automatically color correct a print, and estimate it’s true colors. Although there are still some things to figure out, the outcome so far looks very promising, so here are a few preliminary results (top raw, bottom corrected):

yotsuya said:

But I think I’ve found the single worst scene in the BR. When the Sand Crawler stops and the Jawas come in to select the droids to sell. R5-D4 is more pink than red. Any ideas on that shot? I thought I had it but I’m going to totally redo it.

I’ve not looked at that shot yet, but from your reaction, I can probably conclude it will be a challenge 😉.

towne32 said:

DrDre said:

Here’s a set of the regraded shots:
…

…

Looks like an impressive gallery!

Except this one still looks like it has wonky contrast to me. 😃

Yeah, I don’t really like that one either… I also noticed R5-D4 has turned orange, which will need to be fixed.

Regarding Peter Cushing’s skin tones, he wasn’t tanned, but he wasn’t pale as a sheet either:

Here’s a set of the regraded shots:

I think these last two still are a bit too green.

Here are the two Motti frames with the latest color grading:

Then I misunderstood 😃. One thing I do notice for your correction, is that Darth Vader’s belt lights have turned blue.