Dealing with fogged E-6 film
Alright guys, this is for anyone interested, something I whipped together to start experimenting on, I've made my own first developer as a test, this was the 2nd test, and the first with success (of some measure).
Just to show that aged/fogged slide film isn't necessarily useless and irrecoverable.
I had made several attempts before this with latent image bleaching techniques, and bleaching post first development but pre colour development among things, so far this has been the most effective and simplest method, brewing my own first developer to compensate for fogged film, as I've done with colour negs.
I'll just leave this pic here of the results thus far, far from happy with it (want better colour, change tone curve a bit), is a bit speed losing, and base does look like the film is very slightly aged with the lightest hint of base fogging (need more dMax) like it's been well stored instead of poorly stored.
But if you can recover this much from something that badly fogged, more smaller adjustments could be made, and film that's not nearly as badly as fogged is also going to be able to get great dMax.
The film is some really old Kodak EPN I found in a bulk loader.
I do knw that older slide film can be processed within some success. A kind of pull processing with less thiocyanate as usual will be fine at first.
Would you be so kind to post your FD formulae?
Do you brew up your own CD as well? Basically you have to if you want the maximum out of aged Film, use less or no citracinic acid at all, adopt pH to best possible color rendering, possibly adopt iodide potion to the as well changed iodide potion in the FD.
The point I don`t get here is the bleaching past FD. Is this a rehologenating bleach? I do know this for color negative processing in order to increase contrast and saturation. But don`t you get results in the wrong Direction? I mean, if you rehalogenate a developed film after FD, do a reversal and than the CD step I would suspect the CD not only do develop all the silver bromide “left over” in order to get a positive picture, but some rehalogenated, former developed areas too. I mean a white object captured on film would be reduced to metallic silver during FD, the following CD can not develop anything more, so no Dye`s are produced, the silver will be blech(fixed) away in the next step and a translucent area will appear, our former captured white, reversal processed. Won´t you get more a kind of grey if rehalogenating prior CD??
All the different types of bleach to modify the image were failures or very limited successes. The idea to bleach the image partially after first developed, is to reduce the developed negative density, thus leave more room for positive density. Didn't work well. They were rehalogenating bleaches, either potssium ferricyanide or potassium dichromate based. They act selectively on different areas first, depending if its latent image or developed negative. I tried latent image bleaching with dichromate, which acts as much on lower exposed areas on a latent image as well as higher exposed areas, some small success, not enough bleaching. But I stopped, and just thought that I know that it can all be done in developer.
This example, only uses customs first developer, thats it, and stop after FD instead of wash, then process carried out as normal, nothing else modified, the film was then started in reversal bath in a dip and dunk processor.
I left thiocyanate level at 1g/L (I used potassium thiocyanate) first. I plan on using thiocyanate to affect yellow/blue colour balance instead, so modifying it in small amounts.
IIRC, what I used was this, the general tonality didn't please me, but EPN was never my thing as far as I know anyway, it needs more work:
23 g/L Sodium Sulphite
4 g/L Hydroquinone
0.5 g/L Metol
18 g/L Sodium Carbonate Anhydrous
7.5 g/L KBr
1 g/L KSCN
10 mg/L KI (5mL 0.2% KI solution)
You only need the basic chemistry to do this, no rolling your own colour dev (well you still need access to the rest of E-6 kit). KSCN was cheap off ebay.
Found some notes.
The dMax of strip through standard E-6 is 0.95, 1.59, 1.03
The above modified recipe (as seen on the strip itself) measured 2.42, 2.71, 2.22
I thought so, this bleaching in reversal processing, or the limited success of this bleaching prior CD is somehow logic, you may increase D.max but will fog the highlights too. At least my tired brain tells me that
Inreasing Iodide in the FD and decrease Iodide in the CD is another option to boost the blue sensitive / yellow forming layer a bit. That was the way I could get rid of a nasty magenta/blue color shift some time back. The red/green axis can be controlled (depends a bit on the Film) by pH of CD, Yellow dye buildup was increased by the Iodide Variations. Watching at your formulation, your FD already contains quite a lot of Iodide, but this is (was) not uncommon for Hydroquinone based FD’s, to overcome the high activity compared to HQMS… Maybe increase it a bit further to about 15 mg/L.
Lowering Thiocyanate solves less silver, more silberbromide can be developed. The effect is , as far as I know, also more prone to the top layers, our suffering blue sensitive, yellow forming layer. That’s another option, you’re absolutely right (Side effect may be lowered contrast and less clear highlights under normal(!) circumstances). In the end I got the best results with iodide variations, Overexposing and pull development, as well as slight pH variations of the CD, for outdated films.
But anyway, for such an old Film the result looks amazing, especially if compared to standard development. It will hardly get any better, but hey, it’s just a game/hobby, no serious work…
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This is neat stuff. Way over my head as I've only done basic b&w dev at home (fool-proof D76 and HC110), but quite interesting that you were able to affect results so much.
Thanks for putting this out there.
Just a mind game…
In order to increase saturation and density of aged slide film you could try something like this…
-Overexpose film for about one aperture (or more if needed)
-Do a pull process in the FD, in order to keep halfway enough silverbromide left over for the following steps.
-stop and rinse good
-use a NONrehalogenating bleach, as used in BW reversal (dichromate/sulfuric acid) to get rid of the former developed silver. Maby use a clearing bath as used in BW reversal too.
-Wash well, do an optical reversal exposure with a flood light
-Do use now a color developer with less CZA as usual, keep dev. time/circumstances normal.
-Now use a rehalogenating bleach, wash well afterwards.
-Do an optical reversal again, followed by color development number 2.
-From now on process as usual, this should increase densities and contrast (possibly all other color deviations too)
-Spend a few days in the lap to optimize the process (till the film is finally all used up)
I tried B&W bleach to build up density that way. But I last time I did it I used sodium bisulphate from a pool shop, my bisulphate must be contaminated with chloride or bromide because it is partial rehalogenating, and I dont know where my sulphuric acid is.
I've done a pull process on this film before, 2 stop pull got this film to around ~2.8 on the density scale, lowered contrast though, trying to avoid the pull process look.
Maybe do a rehalogenating bleach before you load the camera, let it dry and load into the camera for picture taking. Wouldn't that remove the fog? What about sensitivity - would that still be preserved? Just a thought might be worth experimenting with. PE probably has the answer. He has forgotten more about silver halide/photo related organic chemistry than most of us will ever know.
Shoot more film.
There are eight ways to put a slide into a projector tray. Seven of them are wrong.
I've done a potassium ferricyanide + potassium iodide bleach, but it was extremely uneven, unlike with bromide, but with bromide, the fog will go back to silver bromide, but I think it'll displace the silver iodide into silver bromide as well.