Split toning when bleaching

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I hope you can help me save a little time tracking down the cause of this problem. Lately I have had more than my share of problems with locally bleached areas of a print toning a very different shade than the rest of the print when toned in selenium. The prints were bleached with potassium ferricyanide applied locally with a small brush. Although I bleach only rarely, this now ruins more than 50% of my bleached prints. Many times prints of the same subject, made at the same time and procesessed and bleached identically (or as close as I can) will display this fault while others do not. Typically, the bleached area tones lighter and redder than the rest of the print. My bleaching technique is to transfer the print from the first fix to a water bath. There it sits from 30-60 seconds. It is then placed on an angled sheet of plex and the bleach applied. The dilution of bleach varies and seems to have no effect on this problem. Although bleaching is obvious at this stage, there is no change in image color. After bleaching, the print is returned to the fixer for a short time, washed thouroughly and dried. I tone prints at a later time in toning sessions. There the prints are soaked, given the second fix and transferred to the selenium toning bath, usually 1:9 or thereabouts. It is at this point that the split toning appears. I have no clue as to why this appears in one print and not another. I use TF-4, Kodak and Ilford rapid fixers at "film strength" and give 60 seconds in each bath as per Ilfords recommendations. The fixer is never used to capacity. I'm wondering if the rapid fix or the dilution has any role in this since the problem has increased since switching to this method from the more traditional scheme of conventional non-hardening fix for first bath (3 min.) and plain hypo for bath 2 (also 3 min). Any ideas, help or experiences would really be appreciated. Thanks in advance for taking time to read this and respond. I'll be happy to provide more details if this is not sufficient. Regards, ;^D)

-- Doremus Scudder (ScudderLandreth@compuserve.com), November 05, 2001

Answers

My experience is that print color after bleaching is very much dependent on the type of paper. The warmer the paper, the more likely you are to get a split after selective bleaching. Warmer papers have much finer silver grains in their emulsion to start with. If you have a paper that is somewhere in the middle between cold and warm, it is already halfway there, and selective bleaching reduces the silver grains to the point where they refract light into the reddish-brown range.

So, what paper are you using? In my experience, you won't have this problem with Ilfobrom Galerie. I haven't used Seagull in a long time, but I'm told that Bruce Barnbaum uses it, and he does a lot of selective bleaching.

-- Ed Buffaloe (edb@unblinkingeye.com), November 05, 2001.


Concur with Ed's diagnosis. I find that bleaching and then toning in selenium actually leads to differences in print color. Since color is intimately tied to size of the silver grain and local bleaching reduces the size locally, there would be differences in color in these areas. The problem appears less frequently with bromide or predominantly bromide papers (e.g., Galerie, Oriental Seagull), primarily because these develop fairly large grains and it takes quite a bit of bleaching to coax color out of them. Good luck, DJ.

-- N Dhananjay (dhananjay-nayakankuppam@uiowa.edu), November 05, 2001.

Doremus:

I believe everyone so far has been very accurate in their estimate of the cause of your problem. Most papers are a mixture of bromides and chlorides. This is true for a lot, if not most, of the graded papers and all of the VC papers. That's why you get split toning with VCs, and that is probably related to what you are getting here. The two types of emulsion are probably bleaching at different rates, resulting in a shift or split in tone.

-- Ken Burns (kenburns@twave.net), November 05, 2001.


Doremus,

As well explained above, split toning will usually be more obvious with warm-tone papers. And every step from filter selection, to development formulae and time/temperature composite may show some sort of consequence. By now, I gave up worrying about that. I prefer to play around. Heavy bleaching plus seleniun and, sometimes, gold toning also, will add some quite interesting effects to high and low values. And if these bother me, it's Ok, just gotta change to cold tone paper. Anyway, maybe you could try bleaching with some permanganate formulae wich are supposed to withstand toning on better mood. Regards,

Cesar B.

-- Cesar Barreto (cesarb@infolink.com.br), November 05, 2001.


Thanks for the responses all. I thought I had covered all the bases and given adequate info about my materials and technique, but obviously, I neglected to mention the papers I use as well as a few other things. To "thicken the plot" so to speak, here is the rest of the info: I use primarily graded papers and have been having my problem with Oriental Seagull G, Zone VI Brilliant (which I think is an Ilford product similar to Ilfobrom of old) and Bergger NB. As I mentioned earlier, this is a recent problem and did not occur with anywhere near the frequency until just lately, all with the same set up with the exception of fixer types. The problem does not seem to be brand related. Is it possible that rapid fixers contribute to the split toning, or bleach dilution, more or less bleaching time, brush type, or...? I'll keep trying to track down the cause and report if I find one. Any further ideas would be appreciated. Regards, ;^D)

-- Doremus Scudder (ScudderLandreth@compuserve.com), November 06, 2001.


If the only thing you changed was fixer, I would go back and try it with your old method.

In my own practice of selective bleaching, I use rapid fix, usually Ilford, at their recommended dilution of 1+4, but I rarely use it on any paper other than Ilfobrom Galerie unless I desire the change in color. Galerie, of course, is well known for being hard to tone in selenium.

-- Ed Buffaloe (edb@unblinkingeye.com), November 06, 2001.


Hmmm, stranger and stranger.... I take it you are trying partial bleaching. What about bleaching the spot away completely and refixing before toning? Nothing left in that area for the toner to work on, so you'll end up with a white spot that can be spotted in. Good luck, DJ.

-- N Dhananjay (dhananjay-nayakankuppam@uiowa.edu), November 06, 2001.

Another thing that comes to mind is that fix is a silver solvent in and of itself. It may be that a stronger concentration of ferricyanide worked well with standard fix, whereas you may require a lesser concentration when using rapid fix.

I mixed up some iodine bleach, but I'm still experimenting with it. Early impressions are that it gives much cleaner whites than ferricyanide but, of course, it is still reducing the grain size where it doesn't bleach totally, so it does produce a change in the overall emulsion color. I haven't gotten to the point of trying it as a selective bleach.

-- Ed Buffaloe (edb@unblinkingeye.com), November 07, 2001.


Interesting idea, Ed. And IF that is the problem, maybe moving to an alkaline fix would cure the problem since alkaline fixers don't bleach the silver image. Not to mention that they are supposedly a lot easier to wash out of the emulsion. Wonder why they aren't used for paper, given what an issue washing fibre based paper is. Cheers, DJ.

-- N Dhananjay (dhananjay-nayakankuppam@uiowa.edu), November 07, 2001.

I use TF-4 for fiber based paper all the time.

-- Sal Santamaura (santamaura@earthlink.net), November 07, 2001.


One other thing is your bleach is too concentrated, maybe you are trying to bleach too fast? I know i have done this when I want the parts I am bleaching to have a reddish color, I use a more concentrated solution of ferri and no fix, so maybe if you dilute your ferri and use rapid fix after, you will not get the color shift.

-- Jorge Gasteazoro (jorgegm58@prodigy.net.mx), November 08, 2001.

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