Archival Stability Ilford XP2 Super developed in B&W Chemistry

[pentaxuser]

I just did, but here is something more:

https://www.rangefinderforum.com/forums/showthread.php?t=120810
"Like someone just already said...chromogenic film wins by far on latitude...i´ve used extensively xp2 and teh results are really WIDE...check one film under hard light conditions you´ll be able to get a pair or point on each extreme.
Also teh grain is very fine.."

https://www.l-camera-forum.com/topic/182236-dumb-film-question-xp2-exposure-latitude/

Well frankly you haven't actually given a reason(s) you have made statements without citing evidence. I am simply looking for an explanation as to why, per se, C41 chromogenic film gives a greater exposure latitude when developed in C41 as compared to the same film when developed in B&W chemicals.

I am simply seeking reasons and more knowledge of how "thing work"

pentaxuser

 

[MattKing]

The "latitude" is mostly toward over-exposure.
Simplifying tremendously:
Dye clouds get smoother when they become more dense.
Film grain gets "Lumpier" when it becomes more dense.
Caution: "Lumpier" is not a generally accepted technical term.

 

[Svenedin]

The "latitude" is mostly toward over-exposure.
Simplifying tremendously:
Dye clouds get smoother when they become more dense.
Film grain gets "Lumpier" when it becomes more dense.
Caution: "Lumpier" is not a generally accepted technical term.

Yes for C41 processed XP2 Ilford say (according to their data sheet) it can be exposed at up to EI 800 (one stop under exposed) or as low as EI 50 (3 stops over exposed). I've tried it at 800, 400, 200, 100 and 50. It becomes really annoying to print at 100 and 50 (the negatives are very dense). At 800 it's a bit thin but still prints quite well. I prefer it at 200 or 400 but to be honest I don't really like it that much. I just did some experiments and decided that if I had to rely on lab C41 it would be acceptable but whilst I still do standard B&W processing at home (but not C41 at home) I'd rather stick to conventional films.

 

[Nihil Abstat]

The "latitude" is mostly toward over-exposure.
Simplifying tremendously:
Dye clouds get smoother when they become more dense.
Film grain gets "Lumpier" when it becomes more dense.
Caution: "Lumpier" is not a generally accepted technical term.

Yep, that's what I was saying...

 

[Nihil Abstat]

Well frankly you haven't actually given a reason(s) you have made statements without citing evidence. I am simply looking for an explanation as to why, per se, C41 chromogenic film gives a greater exposure latitude when developed in C41 as compared to the same film when developed in B&W chemicals.

I am simply seeking reasons and more knowledge of how "thing work"

pentaxuser

I gave it already. Callier effect absent.

 

[Nihil Abstat]

maybe another reason the OP is processing it in b/w chemistry is because the OP doesn't want to deal with color processing ? ...

Then why use it at all? It doesn't make any sense whatsoever to use it in this way. There is no advantage whatsoever over conventional B&W film.

 

[MattKing]

Then why use it at all? It doesn't make any sense whatsoever to use it in this way. There is no advantage whatsoever over conventional B&W film.

Incorrect.
In many places, there is no easily accessible, competitively priced, reasonable quality commercial processing for traditional black and white film.
So if you want to be able to choose between commercial processing and your own processing, having the option to do so with XP2 is attractive.
I know I sometimes have a backlog of film waiting to be processed. How much does it add to quality of life to know that one can either spend the time and effort to do it yourself, or spend the money to have the reasonably local lab do it for you?

 

[Billy Axeman]

I agree with Nihil Abstat. OP is processing his own film (post #1), and technically there is a disadvantage developing XP2 in B/W chemicals. So, why doesn't he use a decent B/W film. That is still the question.

 

[mnemosyne]

I agree with Nihil Abstat. OP is processing his own film (post #1), and technically there is a disadvantage developing XP2 in B/W chemicals. So, why doesn't he use a decent B/W film. That is still the question.

Because it's there, to quote a famous Englishman, or, because it's there in his fridge, to quote the OP

 

[Billy Axeman]

Bill, what is the technical disadvantage that you're talking about?

The answer to that is in your own question in post #1.

 

[Raghu Kuvempunagar]

The answer to that is in your own question in post #1.

Ian and AgX put my concerns to rest. See #5 and #6.

 

[AgX]

I am simply looking for an explanation as to why, per se, C41 chromogenic film gives a greater exposure latitude when developed in C41 as compared to the same film when developed in B&W chemicals.

The "latitude" is mostly toward over-exposure.
Simplifying tremendously:
Dye clouds get smoother when they become more dense.
Film grain gets "Lumpier" when it becomes more dense.
Caution: "Lumpier" is not a generally accepted technical term.

I gave it already. Callier effect absent.

Both completely off track...

The benefit behind chromogenic b&w film is that by seperating the sensitive part from the image forming part one gains much more freedom in characteristic curve design than with a one-stage concept as in classic b&w film.

Agfa mainly played this concept, whereas Kodak leaned more to the advantage of standardized commercial processing and printing.

 

[Billy Axeman]

Ian and AgX put my concerns to rest. See #5 and #6.

I am surprised you are accepting this so quickly because it seems you have done a lot of homework.

 

[AgX]

Well, hinting at non-cromogenic development to be on the safe side I wrote "not to be expected"...

Furthermore the OP employs a staining developer, thus will receive a dye image in addition. This of course complicates longevity matters.

 

[Martin Rickards]

It seems that we have forgotten the question of longevity mentioned in the OP. Is it worthwhile putting formaldehyde in the final rinse?

 

[Billy Axeman]

Here is some reading about stabilizers:

The definitive word (I hope) on color stabilzers!
https://www.photrio.com/forum/threads/the-definitive-word-i-hope-on-color-stabilzers.89149/

 

[Svenedin]

Because it's there, to quote a famous Englishman, or, because it's there in his fridge, to quote the OP

If he was given a lot of it for nothing it might make some sense but if he bought it knowing he was going to develop it in B&W chemicals then it makes very little sense unless of course it's a question of local availability of conventional B&W films.

 

[Billy Axeman]

Now we are really closing in on the OP.

 

[removed account4]

Then why use it at all? It doesn't make any sense whatsoever to use it in this way. There is no advantage whatsoever over conventional B&W film.

who cares if there is no " advantage " .. or "makes no sense" the OP likes his results.

 

[Billy Axeman]

who cares if there is no " advantage " .. or "makes no sense" the OP likes his results.

A man decides he wants to bake a white bread. He takes 1 kg of whole wheat and starts processing it with his own recipe until he has white flour. He puts it in the baking machine together with sugar, salt, dry yeast etc., and he enjoys the work he is doing.

In the mean time his wife enters the kitchen to see if she can help, and wonders what he is doing. She asks "Why are you buying whole wheat when you want to bake a white bread". He is surprised and replies somewhat irritated: "Well, I like the result".

 

[Gerald C Koch]

I've had some success developing Ilford XP2 Super ISO 400 film in Obsidian Aqua, a staining developer designed by Jay Defehr. Though XP2 Super is a film designed for C41 process, I prefer to develop it as traditional B&W film as I need not rely on commercial labs for developing the film and I can use the developer I've brewed at home. In both 135 and 120 formats, I've got negatives that have good contrast, fine grain at ISO 100, and nice tonality.

One concern I've now is about the colour couplers used in XP2 Super film. In C41 process the couplers would react with the developer and form a dye cloud around the silver grain that was exposed to light. When developed in B&W developers such as Obsidian Aqua I'm not sure what happens to these couplers. I suspect they remain in the film even after fixing and washing. Can the couplers cause any harm to the negative over a period of time?

Another concern I've is about the risk of fungus attack on XP2 Super negatives developed in B&W developers such as Obsidian Aqua. In C41 process the negatives are bathed in stabiliser which contains fungicide. As the negatives have no silver, the stabiliser bath is a must to protect them. On the other hand, my XP2 Super negatives have silver in them and I don't use a stabiliser. Is the silver in XP2 Super adequate to protect the negatives from fungus attack?

The judgement of the marketplace is better than that of single APUUG members. This film was discontinued due to lack of sales. I don't know about others but this fact shouts in my ears. Now were it not for a similar Ilford film I would say that this idea is more appealing. Like a film then buy lots of it or it will go away. Law of Acquisition #153.

 

[JBrunner]

Mountain climbing serves no useful purpose to me. But all who wish to do so, may do so, and I'm not going to question why. Or to wit; the why question is not part of the OP and at this point I consider it a dead horse that is being beaten to the point of derailing the intent of the OP, so we will kindly knock it off, or I will prune the thread accordingly.
That will be all.

 

[MattKing]

The judgement of the marketplace is better than that of single APUUG members. This film was discontinued due to lack of sales. I don't know about others but this fact shouts in my ears. Now were it not for a similar Ilford film I would say that this idea is more appealing. Like a film then buy lots of it or it will go away. Law of Acquisition #153.

Gerald:
XP2 Super is a current Ilford film. Processed in C41 chemicals it yields black and white negatives without any orange mask. Those negatives print well in an enlarger, and they are excellent for scanning too.
The Kodak version is the discontinued film. When processed in C41 chemicals it yielded black and white negatives with the characteristic orange mask, which were easier to print using the colour paper found in most mini-labs.

 

[pentaxuser]

Well as has been said, the OP is clearly getting what he wants from XP2+ developed in the trad B&W process and he has the assurance he needs from Ian Grant and I think one other that his specific concern has been answered.

Are XP2+ negatives as easy to print and are the prints as good when processed in B&W chemicals is a pertinent question, of course for those of us who haven't tried this route. Fujilove gave a link to what turns out to be an e book which might give the answer to my question above but I am not a convert to e-books.

The OP doesn't say whether he has made prints from his negatives but I have a feeling others on Photrio may have

So can I ask, for my own enlightenment, if anyone else point me to examples of prints from XP2+ negative processed on trad B&W chemicals or at least describe how easy they feel such negatives might be to produce prints from ? I extend this request to the OP as well in case he has prints he has made.

Thanks

pentaxuser

 

[removed account4]

Gerald:
XP2 Super is a current Ilford film. Processed in C41 chemicals it yields black and white negatives without any orange mask. Those negatives print well in an enlarger, and they are excellent for scanning too.
The Kodak version is the discontinued film. When processed in C41 chemicals it yielded black and white negatives with the characteristic orange mask, which were easier to print using the colour paper found in most mini-labs.

hey matt

just to add to what you said
not sure who told this to me but the xpsuper negatives
were sometimes printed in a mini lab but the lab sometimes had to
sandwich a sheet of color negative film that had nothing on it but the orange mask
this person told me the brand of film to, "kodak gold"

but YMMV