layers and operation in colour films
I understand that colour films (negative and reversal) have a number of layers for both filtration of frequencies and recording the various frequency bands. I'm looking for a good reference on this (web or book) if anyone can point me in this direction I'd be very interested
: you understand why it should work but it doesn't
: it works but you have no idea how
Here theory and practice meet, things don't work and I don't know why
I do not have a copy, but I understand that later editions of Grant Haist's 'Modern Photographic Processing'.
A quick Google suggestes that Volume II might have more colur information, but if I could lay my hands on a set, I would want all volumes.
I suggest a search though a uni research library.
Yep, Haist is a pretty solid reference if you know some chemistery. I borrowed the two volumes from a local library, and read them as bedside stories while I was working on my MA. It must have taken me a few months to read the two volumes, but boy do you feel clear-headed afterwards!
But if you're just looking to understand how the different layers of colour film work, I suggest you pick up a general purpose photo manual. Hedgecoe's, or the Uptons are excellent and have detailed illustrations. The Life library of photography is good, and so is the Kodak Encyclopedia of Practical Photography. You might find some stuff on Kodak's website as well.
A bit of Googling "how colour film works" can yield useful basic info like this:
Using film since before it was hip.
"One of the most singular characters of the hyposulphites, is the property their solutions possess of dissolving muriate of silver and retaining it in considerable quantity in permanent solution" — Sir John Frederick William Herschel, "On the Hyposulphurous Acid and its Compounds." The Edinburgh Philosophical Journal
, Vol. 1 (8 Jan. 1819): 8-29. p. 11
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I have got quite an extensive library but I can't advise on any book if it should reveal much more than the basic 3-layer principle. All the information seems to be spread amongst side-notes, historic references, lectures by the industry...
The best comprehensive text so far I found in Dutch book, so it won't be useful to you. And even that speaks only of two halide layers per colour, whereas meanwhile three is common.
the principle is as follows:
-) the basic layers are typically placed in the sequence (surface to base)
in addition of course
to make it more complicated
many films of today have the colours layers seperated in two or three sublayers with a different scope of crystal sizes, which makes 1x2plus2x3 or 3x3. Behind this are similar thoughts as in BW multilayering: control of gamma, latitude, grainularity. The sequence is high-, medium-, low-sensitive.
red (or magenenta) filter-layer
seperation-layers between the colour groups
for the yellow filter-layer Carey Lee silver (collodial silver) is the classical approach, however a more modern concept employs a dye as its absorbtion charecteristics are more profound.
The thickness of most layers will be less than 2μm.
Last edited by AgX; 04-16-2008 at 02:04 PM. Click to view previous post history.
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There are a few more than AgX lists above but he is correct in the essentials. See the cross section I posted here on color film. It shows and identifies each layer. It is in the emulsion making and coating forum.
Basically it is /overcoat/fast blue/slow blue/CLS/fast red/IL/fast green/slow green/IL/slow red/AH/subbing/support/AC/. Sometimes the fast red is under the greens and sometimes not depending on film. On the back are antistats, anticurl and other things. Subbing is present sometimes for example, but in some films it is not present due to the method of manufacture.
See the excellent article by Chuck Woodworth from Kodak on (I believe) howthingswork.com .
Originally Posted by Photo Engineer
Which ones did I leave out?
You left out some interlayers and the division into fast and slow components.
Awww heck, here it is again. Note that the labels don't distinguish fast and slow layers, but they can be seen in the light and dark colors in the example. This also shows the UV overcoat and does not show component inversion.
It varys with each film.
My apologies, I missed part of your post. You have everything there needed. Sorry.
I seldom see Hunt's book," The Reproduction of Colour" recommended, but this would be high on my list. I seldom see it recommended, but if your goal is to obtain a fundamental understanding, I think it's hard to beat. http://www.amazon.com/Reproduction-C.../dp/0470024259
The section on colour neg films (Chapt 12, Subtractive Methods in Colour Photography; see the section on Integral Tripacks, I believe) is short, but fairly comprehensive, discussing reasons for the order of layers, etc. As I recall, it has several cross section photos of color negative film, etc.
If you are after PRACTICAL information, this is probably not a good book. But if you want to understand WHY things are done, you ought to have a look.