But her costume isn't white, at least not compared to the stromtroopers.
depends. in that corridor of the tantive, as far as the DE LD is concerned and the SE DVD, there is a creamy cast to her dress. it certainly doesn't look white in comparison to the white corridor and the stormtrooper armour which we know is white
but I'm afraid I disagree with you.
reasons for doing so
a) both the corridors of the tantive, and the stormtrooper armour were made from vacformed glossy plastic so it's white point is higher than white material.
b) later in the film, when leia is in her cell
i) when vader enters with the interrogation droid
ii) when luke comes into her cell
she is wearing a white dress, it's a bit mucky but it is a white dress.
c) archive evidence. take a look at the Star Wars Chronicles book if you can. (this is a huge hardback, coffee table glossy book, packed with hundreds of reference photo's from the lucasfilm archives.) in it are pictures of Leia's costume. it is plainly white.
also, publicity photo's of the day, show her dress to be white. they can't all be wrong.
screenie 5
yes, the top shot is yours. bottom shot has been adjusted using tweak, msu smart sharpen, RGB and white balance adjustment.
again this is a thorny shot. In the canyon sequence, luke's tunic changes color about 5 times. even allowing for film stock and different developing solutions on different days, I think this is more a case of the fact they made about 10 of these tunics and they got mucky in varying degrees in the tunisian desert and the canyon scene was shot over 5 days*.
(the unofficial making of star wars), so it seems probable that mark hammill wasn't wearing the same tunic on some of the days of shooting during this sequence. further examination of archival material indicates that the tunic was white but got mucky from desert dust and stained varying shades.
the white balance filter can be found her :
white balance filter
it is a good filter, but now that I've got everything else into script and have found an acceptable (but faster) way of getting a sharp interim file without using MSU, I don't need to be using vdubs full processing mode, which saves me a colorspace conversion step.