How to process old E100VS with BW chimistery

[esox]

Hello,

I have lots of old E100VS ektachrome 120 films. I tried a Rodinal 1+100 stand dev for 1 hour and Agfa fixer. I got something on the film but the film itself is very opaque. Is ther something I can do to have a more transparent film ?

Thanks !

 

[Donald Qualls]

You could process it in C-41 to get funky-colored negatives. Or you could get an E-6 kit and process it the way it expects. E-6 films seemingly hold up well after expiration, compared to B&W or even C-41. Usually little or no speed loss (possibly because fog lightens the final slide, instead of darkening the negative?). If you have several rolls, it would be economical to process it yourself in E-6 chemistry, vs. sending it out -- and you'll surely get better images than in Rodinal.

 

[Anon Ymous]

...I got something on the film but the film itself is very opaque...

This could have several causes:

1) The film is old and some base fog could be expected.
2) Development for that long, even if stand developing could increase base fog. Perhaps not by much, but this could be contributing.
3) This film probably has a yellow filter layer made of silver. Yes, real, metallic silver. When developed in E6 (or even C41) chemicals, it is removed by bleach and fixer.

I'd say a combination of 1 and 3 makes your film opaque and there's not much you can do to get clearer film if processed as BW negative. I'd try E6, or C41.

 

[esox]

Ok thanks. That was a try...

What do you thing af opened tetenal E6 chimistery kept in fridge and dark for 4 years ?

 

[Raghu Kuvempunagar]

3) This film probably has a yellow filter layer made of silver. Yes, real, metallic silver. When developed in E6 (or even C41) chemicals, it is removed by bleach and fixer.

I'd say a combination of 1 and 3 makes your film opaque and there's not much you can do to get clearer film if processed as BW negative.

If it is primarily #3, then OP can check out @David Lyga's method.

 

[Anon Ymous]

If it is primarily #3, then OP can check out @David Lyga's method.

You could probably get away with using a rehalogenating bleach (potassium ferricyanide + potassium bromide) as a first step, then a good rinse, followed by whatever regular BW chemicals you use. This will clear the colloidal silver layer, but I'm not entirely sure how much it will affect the latent image. I suspect the OP doesn't have any rehalogenating bleach, so didn't bother proposing this. IMHO, this is a bit too much of an effort. I'd be more inclined to try cross processing in C41. Speaking of which, his already processed film can be bleached with the aforementioned bleach, then processed in C41. This will likely give a colour negative image, obviously with weird colours . I haven't tried it, but suspect it will work. Instead of C41, one can also use E6 chemicals, but skip whatever is before the colour developer.

 

[Donald Qualls]

You could attempt to process in that old, cold, Tetenal E-6 kit, but I wouldn't be confident. At the least, I'd start with a test roll shot for the purpose. IIRC, most E-6 kits one-shot the first developer, but reuse the color dev and blix. Leader tests will at least let you tell if the developers are dead -- they won't tell you if you're going to get color shifts, crossover, and other unpleasantness. If both devs test okay in a leader test, I'd probably go that way.

If the density is some combination of fog and silver filter layer, you might also process by B&W reversal to obtain a B&W positive image. It's more complex than regular B&W negative, but doesn't require the high temperature and tight temperature control of color processes. In addition to your existing chemistry, you'll need a silver bleach that doesn't rehalogenate (so not C-41 or E-6 bleach or common Farmer's Reducer type with ferricyanide and thiosulfate). The one exception to this (which I haven't tried myself) is that if you rehalogenate with chloride, the silver chloride is soluble in plain ammonium hydroxide (clear household ammonia, or some dilution from it) -- but the bromide and iodide of the original emulsion are not. I'd surely test this with B&W test film before trying it on your Ektachrome; at the least, you need to know how strong and how long for the rehal and ammonia baths. VERY effective darkroom ventilation, please!

 

[Raghu Kuvempunagar]

You could probably get away with using a rehalogenating bleach (potassium ferricyanide + potassium bromide) as a first step, then a good rinse, followed by whatever regular BW chemicals you use. This will clear the colloidal silver layer, but I'm not entirely sure how much it will affect the latent image.

This is not a good solution actually and isn't what David prescribes. His method worked fine on C41 films I've tried. Worth looking at it if OP has the necessary chemicals.

 

[Anon Ymous]

This is not a good solution actually and isn't what David prescribes. His method worked fine on C41 films I've tried. Worth looking at it if OP has the necessary chemicals.

I know it's not what David describes, but this doesn't require putting much attention to it, it's a process to completion kind of thing. There's no "snatch point" to keep an eye on for. Once the filter layer has been properly bleached back to silver bromide, you're fine. I'm sure David's method works, there's no doubt about it, but there's the risk of losing shadow detail, that's all.

 

[Raghu Kuvempunagar]

The one exception to this (which I haven't tried myself) is that if you rehalogenate with chloride, the silver chloride is soluble in plain ammonium hydroxide (clear household ammonia, or some dilution from it) -- but the bromide and iodide of the original emulsion are not.

A rehalogenating bleach consisting of Copper sulphate + Sodium chloride (acidified suitably with Sulphuric acid) serves you well in this regard though it's a little slow. This is essentially Athiril's method and has worked well on all the films I've reversed including some C41 films. 2% ammonia solution works fine and clearing of silver chloride takes hardly two minutes.

I did try Ferricyanide + Sodium chloride rehalogenating bleach in B&W reversal. It didn't work well and I didn't investigate further. If made to work, it would be faster than Copper sulphate bleach. But nothing beats the efficiency and convenience of dichromate bleach in B&W reversal.

 

[Raghu Kuvempunagar]

. There's no "snatch point" to keep an eye on for.
..
there's the risk of losing shadow detail, that's all.

There's a snatch point - watch out for the clearing of inter-frame gap. It works fine for 35mm film at least but might need some practice to get it right.

Regarding shadows, a stop of extra exposure generally suffices.

If OP wants to try David's method, I would suggest doing it first with short strips of film instead of an entire roll.

 

[Donald Qualls]

But nothing beats the efficiency and convenience of dichromate bleach in B&W reversal.

I wouldn't recommend potassium dichromate (though it's what I used back in '05-'07) because of environmental and health concerns. The hexavalent chromium is acutely toxic, a suspected carcinogen (might have been confirmed as one since I last checked), and in some areas (EU) may be very difficult to obtain or legally dispose of, mainly due to its environmental hazards. Dichromate is the one photo chemical for which I've always worn both protective gloves and safety glasses. In today's world, I'd stick with a chloride rehal and ammonia process, if it does the job (and it seemingly does).

 

[Raghu Kuvempunagar]

I wouldn't recommend potassium dichromate (though it's what I used back in '05-'07) because of environmental and health concerns. The hexavalent chromium is acutely toxic, a suspected carcinogen (might have been confirmed as one since I last checked), and in some areas (EU) may be very difficult to obtain or legally dispose of, mainly due to its environmental hazards. Dichromate is the one photo chemical for which I've always worn both protective gloves and safety glasses. In today's world, I'd stick with a chloride rehal and ammonia process, if it does the job (and it seemingly does).

Capacity of dichromate bleach is quite good and keeping that in mind and the usage rate of a hobbyist, dichromate isn't perhaps the threat to environment as it is made to believe. It's possible to reduce the toxicity of used bleach by adding ascorbic acid or dithionite to it. The biggest concern to health is when mixing dichromate powder into solution as there's a possibility of inhaling the dust. You will need a good mask along with gloves and glasses. Once it goes into solution, avoiding spills and wearing gloves should suffice. If you can buy dichromate in solution, you can avoid mixing it. As far as carcinogenicity is concerned, even Hydroquinone, a component of most developers, is a suspected carcinogen. And pyro developers are much more dangerous than Hydroquinone. If you use thiourea based toners in the darkroom, you face risk similar to that of dichromate as they're also toxic and carcinogenic. With good darkroom practices, you can handle all of these chemicals safely. Disposing used darkroom chemicals is certainly an issue and needs to be given due thought and attention. Having used both Copper sulfate and dichromate bleaches in B&W reversal, I find the time saved by the latter valuable. Further, dichromate makes excellent rehalogentaing bleach with bromide/chloride which can be used for intensifying and toning the slides when necessary.

 

[Donald Qualls]

The only times I've mixed dichromate (once to make a 1% water solution for alt-process contrast control, and twice for B&W reversal bleach), lacking a fume hood or proper mask, I mixed the crystals into the liquid outdoors in a slight breeze.

I've never used thiourea toner, though I do recall "taste papers" when I was in high school that had some micro-quantity of that soaked into them, which we were expected to taste (the test being that some are genetically unable to taste that compound, though most can). It probably wasn't known to be carcinogenic yet in the early 1970s, and the amount involved was well below the toxicity threshold. I always neutralized the dichromate bleach by mixing it with the clearing bath (sodium sulfite solution), which turned the bleach from red/orange to green, indicating the hexavalent chromium had been reduced to trivalent, which is much safer in all respects.

Another bleach option for B&W reversal is 12% or stronger hydrogen peroxide acidified with citric or acetic acid. Little risk for inhalation, certainly less hazardous than sulfuric acid (used in reversal bleaches containing dichromate, permanganate, or copper sulfate), and safe for drains (though after use, probably ought to be treated like exhausted fixer). Slow, and you have to take precautions against the dissolved silver resettling on the emulsion and staining, but it does work and may be the most environmentally friendly method. Can't be formulated to rehalogenate, however (as far as I know).

The OP, however, is interested in processing old Ektachrome -- if the E-6 in his fridge is still good (after four years?!), that would be the way to go. If not, a little Farmer's Reducer and a refix will remove the background density that's most likely due to a silver filter layer -- or processing in C-41 will get rid of that along with the image silver while leaving a dye image behind.