is there any way to reduce c41 color negatives?

narigas2006

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i forgot some negatives in the color developer for too long and they ended up really dark. is there anyway to reduce them? thanks!
 

railwayman3

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Agreed, very doubtful. The images in colour film are in different dye forms in three (or more) separate emulsion layers, (rather than B&W where the images are just in metallic silver). I'm sure that any attempt using any form of bleach to remove or reduce the dyes would be impossible to control and would, at the least, destroy any proper colour balance.

Kodak say "Overdevelopment with color negative films in the C-41 process leads to very dark contrasty negatives that have dense highlights lacking in detail with a dramatically increased grain size". So, realistically, if the overdevelopment makes the film difficult to machine print by a lab, the only plan would be to try individual "hand" printing from the negs, either darkroom or scanning.

OTOH, there is a lot of latitude with colour negative film, so that might be worth a try.
 
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koraks

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Overdeveloped C41 film will not print in the darkroom unless masking is applied. You're opening quite a can of worms in that scenario. 'Latitude' is not really something that applies if you overdevelop film - we're not talking about overexposure here, which will result in some problems but which is generally not too much of a problem for the average amateur; just print through the excess density and correct color balance as well as you can. But with overdevelopment, gamma will be too high and that will take the negative beyond what the paper can record. Hence, masking is the only way out of that situation. The obvious and most feasible alternative is to scan the negatives and do further processing digitally. Given that the overdevelopment was not too dramatic, a scanner may still make sense of the dense images and corrections can be made in digital post.
 

koraks

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@AgX I was not aware of this and it makes my earlier response invalid. I assume this should work for color negative dyes as well looking at the chemistry involved.
 

twelvetone12

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How much overdeveloped? I once baked some films at 43 degrees (ooooops), and while the results were far from ideal I still managed to make some nice prints out of them.
 

pentaxuser

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AgX the link you provide covers transparencies but does it also cover negative dyes? It was negatives that the OP overdeveloped

OP do you scan or darkroom RA4 print? If the latter then if you show us the negatives in the form of digital photos of them we might be able to say if RA4 optical printing will produce OK results. How much over 3 mins 15 secs did you overdevelop?

pentaxuser
 

foc

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There is a school of thought that says any dense colour negative can be printed, just shine more light through it.
With a scanner this is not always possible, hence pentaxuser suggestion of an optical print.
Over developing is different that over exposure but we live in hope.
If an optical print is not feasible, then you could try taking a photo of the neg with a digital SLR and flash.

See this: https://petapixel.com/2012/05/18/how-to-scan-film-negatives-with-a-dslr/



Just a suggestion.
Let us know how you get on, please.
 

pentaxuser

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Well the OP hasn't been back on Photrio since he posted on Monday but hopefully he will and tell us how much longer than 3' 15" his film was in developer. I once overdeveloped by only about 40 secs and the negs printed OK but the contrast was raised quite a bit. The use of the word forgot may suggest that it may have been a lot longer than a minute but this is just speculation on my part.

Out of interest It would be interesting to hear from others' experiences of overdeveloping and subsequent problems, if any, with optical printing. At what point in time beyond 3' 15" does a negative become so dense that printing would produce a totally unsatisfactory result?

pentaxuser
 

Rudeofus

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Kodak has once published a document E71 describing how to retouch color negative film. Right now it's only available through their Russian website, get it while you can!

Notably absent from this document are any means of reducing density, the whole document is about adding density. This is in stark contrast to their E6 retouching document, and suggests, that C-41 dyes are not meant to be removed - ever.
 
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AgX

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That is why I did not link to it above.

In that manual on negative films it is stated that the dyes in negative film cannot be reduced as them being located in seperate layers. But so are the dyes in colour reversal film too...
Dyes may differ between individual emulsions, but there is no basic difference between imaging dyes in the Kodacolor and the Ektachrome type, other than their spectral density.
(The dyes in CN film are meant to be seen by the paper and the dyes in CR film are meant for the human eye.)
 

Photo Engineer

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Masking is proportional to image density for each masked color up to Dmax, where further dye formation is impossible and thus nothing can help. Therefore, if Dmax is not achieved, the image will be fully masked, just dense.

Kodak did publish a set of bleaches for color negative dyes, but as you see from the ones above, three are used for the three Ektachrome dyes, and presumably 3 would be needed for the 3 C41 dyes. Another problem is the possibility of the bleach destroying the masking dyes as well as the image dyes.

Due to the latitude of color negative films, I would think that they might be printable even with this error.

PE
 

koraks

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Photo Engineer said:
Due to the latitude of color negative films, I would think that they might be printable even with this error.
Click to expand...
Given potentially significant overdevelopment? I have pretty bad experiences with that. Overexposure - okay, not optimal, but printable. But overdevelopment is problematic in my experience.
 

Photo Engineer

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I agree and I have posted this in the past, but in this case, what is done is done! It is printable, but not of high quality. Reducing the dyes may make things worse than printing as is.

PE
 

koraks

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I agree; we sometimes have to go with what we have. I find the possibility of reducing dyes interesting, but more from a theoretical viewpoint. I read that Ektachrome retouching pdf with great interest!
 
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