Estimating the original colors of the original Star Wars trilogy — Page 3

For the latest correction I used a mix of frames, which includes some with deliberate biases, which might affect the quality of the outcome. I’m working on a method to automatically select a set of suitable calibration frames.

I really like how most of those shots came out. Think this can be used on the the released SSE, or the TESB and ROTJ Grindhouse versions?

It can only be used on the uncorrected print. Once the colors have been changed by curves adjustment, the original color distributions and their relationships have sadly been destroyed. I think TESB Grindhouse is uncorrected, so it should work for that release. Williarob is interested in using this method to color correct the high quality scan of the LPP that piota has done. So, I certainly am interested in assisting him with that.

I thought ESB had minor color correction but I might be wrong.

From TN1’s description.
“Corrections : Minor cleanup with some color correction.”

DrDre said:

Williarob is interested in using this method to color correct the high quality scan of the LPP that pitta has done. So, I certainly am interested in assisting him with that.

How do I <thumbs up> <like> <love> or all of the above a post with this new forum software?

-G

Here’s a set of tweaked shots, that is probably more representative of what a final color grading would look like, based on the results I presented before:

Looks better IMO! There are some weird pink highlights in a couple place though such as the horizon in the “look sir droids” shot and tantive walls in the third image.

towne32 said:

Looks better IMO! There are some weird pink highlights in a couple place though such as the horizon in the “look sir droids” shot and tantive walls in the third image.

I applied a global correction to the entire first reel, so any variation between shots has not been corrected.

Would it be possible to show us what things look like if done on a shot-by-shot basis?

This is really impressive. I’m amazed that an automated tool can generate such good results. Do you do this kind of thing professionally, or is this just a hobby?

Darth Lucas said:

Would it be possible to show us what things look like if done on a shot-by-shot basis?

It’seems not really possible on a shot-by-shot basis, as you need sufficient frames with neutral lighting to calibrate the model.

canofhumdingers said:

This is really impressive. I’m amazed that an automated tool can generate such good results. Do you do this kind of thing professionally, or is this just a hobby?

I do work with images professionally, but these algorithms are just a hobby.

So is an entire reel the ideal sample size?

Not necessarily. I’m still trying to figure it out, but in theory you could use a single frame, although in practice the results are less reliable.

Another thing that the automatic regrade seems to agree with is the notion that the Tantive IV walls have a hint of mint:

Blackmagic should purchase your algorithms for use in their software.

brycebayer said:

Blackmagic should purchase your algorithms for use in their software.

They should. But then our luck around here has run out. 😃

DrDre said:

Is it just me or does this seem to flatten colors a bit? like a color banding effect. i am thinking this in the faces on these two. perhaps it is just on the compressed versions you posted.

It’s probably the sample itself. A lot of people were complaining about the compression when it was first released.

DrDre said:

a hint of mint

Dibs on this band name.

I don’t have much to add, but I just wanted to let you know that I’ve been following this project for months and that the results are absolutely fantastic! I’d be interested in seeing them applied to other films as well!

An important thing to consider, when correcting a faded print, is that print colors are not made up of red, green, and blue (RGB), but of yellow, cyan, and magenta (YCM). So, in principle to color correct a print, you’re attempting to reconstruct the original color distributions of yellow, cyan, and magenta, which have shifted. It is IMO not correct to do curves adjustment in RGB color space, as you are unwittingly altering the shape of the distributions of yellow, cyan, and magenta. One of the key assumptions in the automated color correction algorithm, is that the shape of these color distributions remains unchanged, and that they are simply shifted to different intensities. At this point I’m using the standard RGB definition of the colors yellow, cyan, and magenta. However, real film yellow, cyan, and magenta probably are a slightly different mix of red, green, and blue. It is therefore expected that the colors will be more accurate if the approriate mixes of red, green, and yellow are used.