DrDre

Chewtobacca said:

DrDre said:
Take the example of the film Gladiator:

Is your example from the remastered BD or the previous one? The former has color-timing that is noticeably different from the latter, which matches previous home-video releases and the HDTV broadcasts. I’m just curious as to which you chose.

I picked an example I found on a website about color grading, so I’m not sure which version this is.

On the Star Wars Legacy Edition forum Mike Verta posted a preliminary frame of his restoration:

This frame is interesting, since it has a green cast. Color balancing the frame gives the following result:

Given Mike’s meticulous nature, you would expect the green cast to be delibirate, and therefore the color balanced frame would be inaccurate.

Here’s a screenshot comparison:

http://screenshotcomparison.com/comparison/173749

Like poita said, there is a danger in assuming colors should always be balanced. Take the example of the film Gladiator:

The above image shows what was shot on camera, while below is what is seen in the final film. Color balancing the below image with the algorithm, results in an image that closely matches what was shot on film, but not what was seen in theatres:

Here’s an example of a frame for THX-1138 posted a few days ago.

35mm:

Laserdisc:

The 35mm has a (delibirate?) green cast. Using the color balancing/restoration algorithm results in a color palette that is similar to the Laserdisc:

Here’s a screenshot comparison:

http://screenshotcomparison.com/comparison/173753

While I agree with poita’s reasoning, one of the reasons for developing the algorithm, is that good color references might not be always available. In such a case you essentially have to estimate the correct colors for each scene.

Interestingly the original Obi-Wan cloak was auctioned not so long ago. Here’s a photo of an accurate reproduction:

UnitéD2 said:

I agree for the white balance. It’s pretty clause to what I obtained, using the smoke on the Jawa’s left as neutral reference.

I think we have the good color balance, but there’s probably a choice to make about the saturation (could the LPP or the scan be under or over saturated ?).

I think it’s difficult to say at this point, until we’ve seen more of poita’s scan of the LPP. The frames he’s posted and shared with me look really good in terms of both brightness and saturation.

I think the Owen/Luke/C-3PO frame benefits most from a simple white balance, after the global correction.

After white balance:

After white balance + gamma correction:

poita said:

Agreed. Ben’s cloak doesn’t look right though.

I am so keen to try this out, can hardly wait.

Yes, Ben’s cloak tends to come out too green. There’s actually now an option in the algorithm, that should improve the results for such inherently unbalanced frames. It’s a bit technical , but it involves increasing the bin size of the color intensities that you assume should be balanced. After increasing the bin size Ben’s cloak looks better:

…and after a gamma correction:

It’s interesting to note that Obi-Wan’s cloak does appear much less reddish brown in production photos, than most home video releases would have us belief:

Deleted

One of the weaknesses of the color restoration/balancing algorithm, is that it requires sufficient amounts of red, green, and blue (or their mixes) to be in a frame or image, for it to give accurate results. The Luke meets Obi-Wan frames are particulary challenging, because the colors are supposed to be skewed towards the oranges. I’ve been considering how to deal with such frames or sequences. One way to deal with this, is to find areas in the frame that are supposed to be balanced, namely the grey/white areas. Calibrating the color restoration/balancing algorithm on the white/gray parts of R2-D2 for example gives much improved results:

Looking good!

Dreamaster said:

pittrek said:

That’s why I wrote it FEELS perfect and not LOOKS perfect 😃 What I meant was it feels like it was shot on a hot desert planet.

GOTCHA… Your bases were fully covered by good grammar. 😃

To really run this “into the ground” though I did some experimentation.

I took Towne’s 2.7 and PUMPED up the saturation in VLC as well as a slight contrast boost:
Look at how close it is to the IB photo:

And simply for reference, here is Towne’s version with no image filtering:

What does that tell or teach us? In shows us how the RED/GREEN/BLUE levels can be spot on but there can still be tremendous differences visually because of how much Brightness, Contrast, and Saturation can effect the image.

I think the v2.7 version looks perfect.

Here’s what my last corrected frame looks like with a boosted saturation:

I really could not understand why I’ve been getting such inconsistent results. I calibrated the latest version of the algorithm on this frame:

As far as I can tell, it looks just fine. When I apply the correction to other frames, I’ve been getting color shifts, that were mostly yellow/green, but also blue. However, when I examined the raw scan I noticed the relatively large differences in hue, brightness, and saturation between these two frames, that are only a few shots apart:

These inconsistencies are most likely caused by the scanning process, as poita’s scan looks much cleaner, an much more consistent.

The top ones are the -1 raw scan. That image is indeed amazingly vivid.

The top ones are the -1 raw scan. That image is indeed amazingly vivid.

I think they could use a slight reduction of yellow, and a slight increase in red…

Deleted

I’ve updated the algorithm, here are the earlier frames corrected with the updated algorithm:

Yeah, but That’s not what Greedo looks like in the theatrical version. Mike Verta posted his Legacy version a while ago, and it looks like this:

So, that’s nothing like the new photo, which just looks like they brightened the bluray shot to show Greedo more clearly, as towne32 suggested.

nightstalkerpoet said:

Where does reel 2 start and end?

Reel 2 starts with C-3PO taking his bath, and ends with the Death Star conference scene.

Yes, I noticed it too. The reality is, that any color balancing algorithm uses some criterium to balance the colors. Mine is no different. The second reel has a lot of red/orange in almost every shot, and almost no green, meaning that the colors are pretty biased, and therefore unbalanced:

It’s very difficult to find shots with sufficient amounts of red, green, and blue to calibrate the algorithm. I’m trying to figure out a way around this, but this is a bit of a challenge. The current algorithm is less sensitive to this problem, but as these shots show, apparently still too sensitive.

yotsuya said:

Probably funny considering my last comment, but that last image makes Threepio look too bronze (pale and green). Well, he always looks pale in that scene, but not always so lacking in golden tones. Seems to be my complaint with the Tatooine outdoor scenes, doesn’t it? That is one reason I have been relying on the GOUT. It ùhas a consistent coloring for him throughout (as consistent as any color in a SW movie).

As before I used a single correction for the entire scene. One of the difficulties of the raw scan is that the color balance varies quite a bit. Although this could be a problem of the print, at least part of the color cast was introduced during the scanning, as is evident from the examples poita posted of his scan of the same print:

-1 Scan:

Poita Scan:

It is be interesting to see how the C-3PO shot looks for poita’s scan. On the other hand, Star Wars is not known for it’s color consistency.

A nice extra feature of the color balancing algorithm 😉:

Deleted

flametitan said:

It looks a little dark in some areas, but the blues in the sky look great.

I remember a preproduction shot that had Ben’s cloak as more of a grey colour, and this seems to reflect that as well.

EDIT: Well this is awkward.

Sorry, I updated the figures. 😃