hairy_hen said:

I have a feeling it probably works better when the sources aren't too radically different--the scenes of Luke lost in the snow in ESB looked pretty terrible; the colour was mostly right but some elements became inexplicably bright purple(?!) and there was crazy blocking going on in the backgrounds sometimes.  That whole sequence is so screwed up in the SE, it's like there's a thick blue haze over the entire image;

 That thick blue haze over the image is in the original theatrical version too. The SE is actually less blue than the theatrical version for some of this sequence, for instance inside the wampa cave the SE is not very blue from my memory, but the theatrical version of the wampa cave is pretty blue.

Then the blue should be retained. I seem to remember Hoth always having a pleasing icy blue color to it, and that appears to indeed be accurate according to the references, so it all makes sense. :)

Hoth on the 2004 DVD fiasco is more teal than the original ice blue.

Working on colour correction of those scenes now, (using the idea from this thread boosting the saturation on GOUT and then using it as a refrence) I can say that I think the problem is that the SE is more cyan than blue and it's also quite discoloured, i.e. everything has a cyan tint to it including people's faces. When you boost the saturation on the GOUT, the snow gets blue but other stuff retains it's natural colours and that's very tricky to get out of the 2004 SE.

Oh yeah, the SE colours have been completely screwed with. But of course, in terms of the "look" having a bluish cast over the image the way the SE does is much more accurate than the GOUT, which is basically black and white. Luke with the wampa and lost in the blizzard/rescued by Han is the most bluish sequence in the whole film, it's a pretty intense, dense blue, and the SE gets this much better than a lot of other sources, while the GOUT on its own has almost no colour and is in this respect useless. For most of the other interiors, it's sort of in between the two; neither are accurate, the GOUT lacks all blue, but the SE gave the whole image a strong blue/teal tint whereas the original only had a milder tint.

The GOUT doesn't really give you anything like the theatrical colours, so applying the GOUT histograms to the SE is basically purposeless unless you are going to correct them massively from there, although it looks more attractive than the SE on its own. It's a good improvement on the SE, but in some ways it's equally artificial. I think you would have to tweak it all by eye in order to get it to look good; ROTJ on the raw GOUT seems to have suffered the least so those test pics generally hold up though.

I'm not using any histograms, I just colour boost the GOUT and then adjust the SE by hand. I could post some screens later. Or you could check out my workprint if you want, Zombie, although I've already changed the colours quite a bit. It's also that in some scenes the SE is too bright and it's tricky to darken it because of the crushed blacks and overblown whites.

hairy_hen said:

I did a bit of experimenting with the AviSynth filter ColourLike: http://forum.doom9.org/showthread.php?t=96308

Works by generating histograms from one source and modifying another to more closely resemble it.  Tried it on the rancor scene in RotJ, modifying the 2004 version based on the GOUT colours (with a saturation increase and hue shift away from red) and the results seem promising.

More discussion about Colourlike, and other methods of colour matching, can be found in this thread.

Harmy said:

 It's also that in some scenes the SE is too bright and it's tricky to darken it because of the crushed blacks and overblown whites.

 Yeah, that was one thing Adywan ran into when making the ESB Reconstruction. Scenes like some of the Dagobah ones are way too bright, but you can't really bring the levels down without destroying the image so you have to sort of live with what is there. Brightening the image seems to be pretty easy, and luckily this is the more common fix the SE requires.

Talking of overblown whites, I found this shot interesting in the THX WOW! sequence:

It's a frame from the fighter POV shot during the entry into the DS trench. Every other version, including the GOUT, has a solid white frame at this point:

Hmmm...

Intriguing... That's the whiteout frame where they segue between the two model shots, right?

Could you post the frames immediately before and after from WoW!?

You could probably reconstruct the frame using the previous frame and just brightening the snot out of it (assuming there isn't too much movement).

Btw, has anyone tried lowering the overall brightness with levels?

The last integer is the input level.  While you can't recover detail lost (like in the frame posted above), you can bring down the range.  So to lower it 5 points would be: Levels(0, 1, 255, 0, 250).

By default Levels clamps input luma to [16,235], converts it to [0,255] for making changes, and then scales the output back to [16,235].

As such, Levels(0,1,255,0,255), does nothing on a [16,235] clip, but it clamps (or rounds) a [0,255] clip to [16,235].

http://avisynth.org/mediawiki/Levels

Don't let the numbers confuse you ChainsawAsh, the filter works like it should.

There is actually some "super-white" information in the GOUT video - pixels with a luma value greater than 235. (You can see these areas encroaching into the orange region on the waveform monitor.)

However, I don't think reducing the level of these pixels to <235 is going to recover any significant detail.

Video Collector said:

Hmmm...

Intriguing... That's the whiteout frame where they segue between the two model shots, right?

Could you post the frames immediately before and after from WoW!?

1:

2:

3:

Yet another clipped white level example:

^ WOW!

^ GOUT 

The vectorscope on the 2nd image also show the potential problem problem with the reds if you apply any saturation increase to the GOUT video. The grey square represents the legal YUV colourspace (anything outside this gets clipped when converting to RGB for display) - you can see that the red lights are already at the max even before any tweaking. 

Also interesting that the WOW shot has orange lights instead of yellow on the top right panel, and Han's shirt has a red cast to it. Colour timing error or deliberate creative decision? ;-)

the Puggo Strikes Back mkv sample recently released seems to confirm that the blue tint was added to Echo Base as a result of poor color-timing on home releases... I don't know how to take a snapshot on my Mac in VLC, but it looks more like it does in the trailer than in any transfer I've ever seen.

I haven't seen Puggo's latest sample, but keep in mind he is timing it himself to some degree, so if he thinks there should be no blue he might be inclined to deliberately lessen it. On the theatrical bootleg, Hoth has a blue tint throughout that is about halfway between the GOUT and the SE, and which basically is consistent with a re-saturated GOUT. It's also to some degree in later and earlier home video releases than the GOUT. Do you have a cap from Puggo so I can see what you are referring to specifically?

zombie84 said:
Here is a good example of how some of the colour only becomes apparent when you saturate it:

From the ESB trailer:



ESB Bootleg:

PUGGO STRIKES BACK (frame approx.)


In Puggo's capture, the cave appears to be of a cyan color rather than a blue. I don't think he's done anything other than combine two captures to smooth out things that might have gone wrong in one or the other, so the colors should be basically raw.

Oh, well there are a lot of things going on there just because of the capture and correction. The saturation is not quite as intense as it should be, and the shade it a bit off. But it's much closer to the bootleg than to the trailer. But you can see there is (what should be, anyway) blue colouring throughout most of the image, exactly the way the bootleg is.

Yeah, there's definitely some fading and that's why in scenes like the wampa cave there is no other colour than blue, it basically looks like black and white film with a blue filter over it and I don't think that's quite right, so while it looks great (better than I expected actually) it's probably not the most credible colour reference.

This trailer footage is probably not a good reference for the original color-timing, it's not even in the actual film, it's a different take of the scene with it's own timing. It actually looks like it haven't yet been color-timed.