Urgent inquiry: Can (Bleach) cause chromatic aberration?
<snipped>
But regardless of this possibility or not.
I want to know :
Is bleach quinone the cause?
Is the old developer the reason?
- Is scanning the cause?
Yes, I asked the prank customer to send me all the negative ,,Please share additional details on the film stock used and the processing sequence and chemistry. Please also provide the formula of the bleach used; a "quinone" bleach is something I've never heard of.
Urgent inquiry: Can (Bleach) cause chromatic aberration?
There is a cultural center in Cairo that specializes in picture art in general and analog photography in particular.
This center provides acidification and scanning services for an amateur fee ,,,
- They had a deficiency in the availability of (Bleach), but the rest of the acids were abundant, they asked for my help in this matter, and I provided (Bleach Quinone) because its raw materials are readily available at a very reasonable price.
- This happened a few months ago - and things are fine.
- But perhaps the success of this cultural center in providing dark room services at reasonable prices, this disturbed some other snakes.
- This is a picture from a movie that was treated in this cultural center that I am providing them with bleach quinone.
The question is: is the bleach solution the cause of this chromatic aberration.?
A customer sent me that picture and complained that the picture color was not good and the skin color was not normal.
- This client is basically suspicious of him, and suspicions revolve around him. Perhaps one of the spies (the biggest snake) will be the archenemy of anyone who provides acidification service in Egypt, and he only wants to control the Egyptian market.
But regardless of this possibility or not.
I want to know :
Is bleach quinone the cause?
Is the old developer the reason?
- Is scanning the cause?
May God bless you all. I want answers to these inquiries urgently
Thank you very much, Professor Adrian, may God bless you.that almost looks like tungsten balanced film shot in daylight, and then very badly scanned and color corrected.
that being said, I’ve never heard of a quinone bleach... not sure what you mean by that.
Yes ,,I understand this is an alternative bleach that is discussed in e.g. publications on holography. I have no experience with it, but I'd be inclined to stick to a more conventional bleach for color processing. I do acknowledge that there are problems with getting certain chemicals such as EDTA/PDTA or even potassium ferricyanide which preclude the use of a more conventional bleach. Given this situation, I think I'd personally lean towards testing with a simple copper sulfate/potassium bromide bleach, or even a dichromate based bleach (if dichromate is available). The latter would require thorough clearing (eg using a sulfite bath) before subsequent processing steps (fix & wash). No guarantees on compatibility with such bleaches and color negative material however; this is quite beyond the recommended processing chemistry for such film stocks.
In any case, with all these alternative bleach recipes, I would recommend a stop bath after the developer step, followed by thorough washing before bleach, and a very thorough wash after the bleach as well.
My brother Adrian ,,that almost looks like tungsten balanced film shot in daylight, and then very badly scanned and color corrected.
that being said, I’ve never heard of a quinone bleach... not sure what you mean by that.
Teacher, thanks for your kind response.No. Chromatic aberration is an optical phenomenon that occurs when a lens cannot focus all wavelengths of light at the same point. Chromatic aberration is not caused by film processing chemistry.
https://en.wikipedia.org/wiki/Chromatic_aberration
1. I don't know.
2. I don't know.
3. Perhaps; to cause this effect the scanner must be way out of alignment. Maybe the operator wasn't paying attention.
You say this is a frame from a movie; do you know what filmstock was used? How was it processed? It might have accidentally been cross-processed in the wrong chemicals, like an E6 film processed in C-41 or ECN-2 chems. Or it could be a tungsten-balanced filmstock (3,200 °k) that was exposed in daylight (5,500 °K), causing the strong cyan / blue cast. I'm sure someone who is more experienced with movie filmstocks will be able to help you more than I can.
Good luck
I am very happy with this comprehensive response ,,Well, I haven't tried it, so I can't comment on possible problems with this approach. But if you have tried it successfully, that says enough.
As to the problem with the picture you posted, I suppose there are many possible causes or even a combination of causes:
* retention of silver or silver halides as a result of insufficient bleaching and/or fixing
* certain dyes (particularly cyan) remaining in leuko state resulting in severe color shifts; verify if the pH of the last concentrated bath (typically the fixing bath) is around 6.5 and in any case not too low (<5 or so).
* mismatch between light and film type (e.g. tungsten film used in daylight) - this should not be the case if Ultramax was used as it's a daylight film
* use of very old and/or poorly stored film; you mention it's expired Ultramax and this could be (part of) the problem. Faster films generally don't age as well as slower films. As to refrigeration, we can only hope/assume that sellers are truthful when they say the film was refrigerated, but in reality we never know for sure what the storage conditions throughout the entire lifetime of the film have been. A seller who tossed the film into the fridge for a week before selling it is still truthful when they say it has been refrigerated, even if the film has spent years sitting in a warm room prior to being refrigerated for a brief period of time...
* problems with scanning; anything can go wrong in terms of color and contrast when digital post processing is involved.
The way I see it, there seem to be two problems with the example image: dramatically incorrect color balance and excessive contrast. Have a look at the negatives themselves and compare them with correctly exposed and processed film strips that you know are of good quality to see what differences you can spot. I would also recommend trying to re-bleach and fix a few negatives to see if that changes the nature of the images.
In fact ,, I’m happy to know you ,,You're very kind, Mohmad, thank you for your kind words. And if the opportunity presents itself, I will certainly give the quinone bleach a try. It certainly sounds interesting. I don't currently have any potassium persulfate at hand, but I may order some when I get round to it.
Good luck with troubleshooting the problem and please keep us posted if you find anything!
Yes, yes, God bless you, thanks for the advice.If anyone is interested in using a quinone bleach, then very good ventilation is a must. I've synthesized quinone in the past, in small quantity, and it was one of the most irritating, acrid smelling compounds I've ever dealt with. FWIW, PE commented in the past that it's an effective bleach, but care must be taken when using it.
My brother Adrian ,,
I called the lab technician and told me that the movie was (Kodak Ultra Max 400) an expired film and was refrigerated by the seller.
Have a comment.
Teacher, thanks for your kind response.
This is a film treated with (C41) acids produced by Titanl Machinery Company (JOBO) except bleach solution. I have prepared it as I explained (bleach quinone).
I called the lab technician and told me that the movie was (Kodak Ultra Max 400) an expired film and was refrigerated by the seller.
Have a comment.
Theoretically, there is no reliable academic information on this matter.Mohmad, what's the capacity of the quinone bleach? And what's the shelf life?
This image is false ,,There are two primary issues: The contrast is way off, and there's a color cast.
A third issue is that the saturation is a bit much. This has me thinking that the images are probably not scanned right. It might be the bleach, I doubt it's the film that is expired. Expired film generally shows a shifting color cast across the frame and really bad granularity along with super low contrast, and this has the opposite of that.
My dear brother, Mr. AdrianThere are two primary issues: The contrast is way off, and there's a color cast.
A third issue is that the saturation is a bit much. This has me thinking that the images are probably not scanned right. It might be the bleach, I doubt it's the film that is expired. Expired film generally shows a shifting color cast across the frame and really bad granularity along with super low contrast, and this has the opposite of that.
Theoretically, there is no reliable academic information on this matter.
Practically: using a JOBO machine, 24 were processed using one liter. In fact, the life of this solution is rather short, and from the moment of first use it can live for a maximum of two months.
- Noticeable :
It happened once that I lasted more than two months ,, and there were deposits of it ,,, and the next day the deposits melted on their own without a convincing reason.
My dear brother, Mr. Adrian
Please - How can I get the data sheet for this film Ultramax 400
Here it is Mohmad: 245.3kb, PDF format:
http://apps.kodakmoments.com/wp-content/uploads/2017/07/E7023_max_400.pdf
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