My B&W Reversal Procedure

[Triscuitmeniscus]

I’ve been experimenting with reverse processing B&W negative film to make slides on and off for a few years, and have eventually settled on a procedure that works pretty well for me. I figured I’d share some of my notes/experiences on this forum for posterity. 

I’d like to acknowledge that this is the one area of photography that I’ve found where the normally sound advice of just finding a process from an authoritative source and following the directions to a T is likely to lead to failure. Early on I used Ilford’s and Foma’s procedures as a starting point, and neither worked well for me. This is a process where you really have to individually calibrate each step experimentally to get a good system that works for you. 

Film: I bulk load from 100’ rolls of Arista Edu Ultra 100. This may not be the best film to use for making slides, but it’s super cheap and “good enough.” I burned through a lot of film while experimenting and I’d much rather do that with $3 Arista than $12 Pan F Plus etc. The issues I had with Arista/Foma in the past (blue-purple tinted base, super curly) seem to have been rectified in recent years as well. It seems to have a reputation for having a really weak/delicate emulsion for this process, but with the proper bleach solution and reasonable handling this doesn’t cause enough problems to warrant switching films (for me).

In the process of experimenting I found it very helpful to have a couple rolls of test pictures of my cat or girlfriend (or my girlfriend holding my cat) handy, so I could pull off ~12 inches to test develop before I risked a whole roll.

Primary Developer: Homemade D-76 plus “a little bit” of Na thiosulfate pentahydrate, developed at ~19C (room temp in my kitchen, and cooler temps seem kinder to the emulsion). Again, D-76 isn’t known for being one of the best developers for this process but it’s “good enough” for me and it’s what I’m familiar with. I say “a little bit” of thiosulfate because in my experience a lot of the information online calls for way more than you need. I was using 16g/l initially, but that was enough to completely strip off the emulsion leading to blank or at best very faint slides. After some experimentation I’ve found that 1-3g/l is more appropriate. I’ll start with 2g/l and develop a few test frames, and bump it up or down depending on how they turn out. I think that some of the problems people ascribe to the bleach step (for instance having a blank strip of film when you pull it out of the tank to expose) are actually caused by having too much hypo in the first developer. Unfortunately for me the thiosulfate seems to be a necessary evil: without it the whites in the final slide are always a bit muddy. I’m sure there’s a combination of film/exposure/developer out there that will yield good results without it, but tracking down that combination will be a lot harder than just adding a couple grams of thiosulfate to some D-76.

As far as developing times go, the old “time how long it takes a piece of leader to turn dark and divide by 3" method has worked pretty well for me. I may add or subtract 30 seconds or a minute depending on how the first roll turns out, but in general the rule of thumb is good enough for me. I prefer it to the Massive Development Chart because I’m always working a degree or two under 20C, and I mix my own brew so it's possible for each component to be off by a percent or two. 

Bleach: I use potassium permanganate in sulfuric acid, but again at a lower permanganate concentration than many of the more authoritative sources suggest: I’ve settled on 1g/l permanganate final concentration (2g/l for “part A” stock concentration). One of the major issues with permanganate bleach is that it’s almost impossible to get it to completely dissolve at that concentration, which will result in tiny specks of permanganate sticking to the emulsion and causing black dots on the slides. Passing the permanganate solution through a coffee filter prior to mixing with the acid eliminates this. 

For the acid solution I use concentrated sulfuric acid (look in the plumbing section of your hardware store), 10 ml/l final concentration (20 ml/l “part B” stock concentration). Since concentrated H2SO4 is pretty syrupy I actually do it by weight: 18.4 g = 10 ml. Always drop acid to water, and make sure to rinse out the beaker/graduated cylinder to get what’s still sticking to the sides after you pour. I did lab work with H2SO4 on a daily basis in grad school so I’m very comfortable handling it, but a lot of people shy away from it and use Na bisulfate etc instead. I submit that if you’re comfortable developing film at home you probably have the skills necessary to work with concentrated sulfuric acid: wear gloves and eye protection, imagine you’re wearing a wedding dress in a white room and the sulfuric acid is black paint and you’ll be fine.

The separated stock solutions last a very long time (> 6 months at least), but the mixed solution spoils “quickly.” I don’t know how quickly, but it lasts at least a few hours. You don’t have to mix it fresh for each roll of film. You CAN NOT reuse the bleach.

I determine bleach time experimentally by dipping a black developed leader in the bleach solution and timing how long it takes to completely clear, then double that time. Usually this will yield something like 3-4 minutes. That leaves the emulsion soft, but sturdy enough that it will stay intact with reasonable handling. 

Clearing solution: 30g/l Na metabisulfite for 1-2 minutes. When I take the film out of the clearing solution to expose, if the leader has any developed silver remaining I’ll bleach it again for a minute or two until it’s completely gone, then re-clear for 1-2 minutes.

Exposure: This is pretty simple but it IS possible to underexpose. I take if off the reel and either take it outside in daylight or hold it up to a 100 watt equivalent light for ~1-2 minutes. 

Second Developer: I use home brewed Dektol because it’s easy to mix, powerful, and I always think “I can drag out the enlarger and make some prints with what’s left over” (I never do). I imagine just about any developer would do for this step, as long as you let it work long enough. 

Stop: Vinegar or Kodak stop bath.

Fixer: Ilford rapid fixer, 15-20 seconds. I read somewhere a long time ago that fixer can weaken the base or something (???) in this process and so fixing times should be minimized. Regardless if this is true, this step seems superfluous anyway (after sitting in Dektol for 5 minutes I highly doubt there’s any undeveloped silver halide left in my film!) so I feel comfortable with the super short fix time. I’ve never noticed any problems.

All rinses: I rinse between each step with either distilled water (ideally) or tap water (if I’m too lazy to go to the store for more distilled water). I’ve never had any problems with my tap water, but of course YMMV. I do my final rinse with running tap water and then do a ~2 minute distilled water soak/rinse before drying.

Drying: I “squeegee” very lightly with a folded piece of blue shop paper towel. This doesn’t cause any scratches for me but if you’re worried about soft emulsions you could certainly skip this. I then hang them in my bathroom (the most dust-free room in the house) overnight. 

Display: I scan the film as a matter of course but the main way I display the pictures is either by projecting slides, looking at them on a light table, or putting them in those little photo viewer keychains like what you used to get at the beach and giving them out to family/friends. People LOVE those little viewers! 

Edited November 29, 2022 by Triscuitmeniscus
Formatting

[AJG]

When I did  B&W slides I used Kodak Fine Grain Release Positive, a blue sensitive B&W movie print stock.  It was around ASA 3, if I recall.  I shot existing negatives in a slide copying set up with some 4x5 that I set up on a light box.  I developed them in a print developer and selenium toned them so they really looked like good prints.  With the slow ASA and a light box I even managed some dodging on some of the 4x5 negs.  Shooting color slides of finished prints was never totally neutral in color the way this process was, but it was a lot less labor intensive.

[glen_h]

The "Kodak Direct Positive Film Developing Outfit" seems to use D67 (yes, not 76) for the first developer.

Redeveloper is strange, and lasts only a short time after mixing. 

You are suposed to mix it while the first roll is developing, so it will last to the second.

It is called FD-70, and has sodium dithionite, which it seems can develop without exposure to light.

 

Someday I hope to try this out.

The D67 comes in a can of powder, with a bottle inside the can.

 

https://125px.com/docs/techpubs/kodak/j6.pdf

[rodeo_joe1]

14 hours ago, AJG said:

When I did  B&W slides I used Kodak Fine Grain Release Positive, a blue sensitive B&W movie print stock.

+1 to recommending that approach AJ. 

Years ago I was asked to shoot some B&W slides to be projected as the backdrop for a stage performance. I just shot the scenes normally on 35mm film (FP4 IIRC) and then contact-printed them onto a copying film and developed them in print developer. Maybe ID-2 or D163, can't remember which. 

No hassle experimenting with witch's brew reversal baths, holding wet film up to a light bulb, or anything like that. It was pretty much plain sailing and easy. 

These days they'd just use a digital projector - even easier.

And who subjects a bunch of 'victims' to a slide show in a darkened room these days? 

 

Edited November 30, 2022 by rodeo_joe1

[rodeo_joe1]

13 minutes ago, glen_h said:

The "Kodak Direct Positive Film Developing Outfit" seems to use D67 (yes, not 76) for the first developer.

Redeveloper is strange, and lasts only a short time after mixing. 

You are suposed to mix it while the first roll is developing, so it will last to the second.

That's probably an Amidol-soda formula that was much-loved by reversal fans for the 2nd developer. It also had a following by those that liked a 'self-toned' print and didn't mind the darkly-stained fingers it gave as a side effect. 

[AJG]

3 hours ago, rodeo_joe1 said:

+1 to recommending that approach AJ. 

Years ago I was asked to shoot some B&W slides to be projected as the backdrop for a stage performance. I just shot the scenes normally on 35mm film (FP4 IIRC) and then contact-printed them onto a copying film and developed them in print developer. Maybe ID-2 or D163, can't remember which. 

No hassle experimenting with witch's brew reversal baths, holding wet film up to a light bulb, or anything like that. It was pretty much plain sailing and easy. 

These days they'd just use a digital projector - even easier.

And who subjects a bunch of 'victims' to a slide show in a darkened room these days? 

 

One of my favorite photography quotes:  There has never been a slide show that was too short.

[Triscuitmeniscus]

5 hours ago, rodeo_joe1 said:

Quote

No hassle experimenting with witch's brew reversal baths, holding wet film up to a light bulb, or anything like that. It was pretty much plain sailing and easy. 

It's funny, doing contact prints always seemed like a PITA to me: I'd rather expose film to daylight than manipulate film in pitch dark. My other problem is I don't have a dedicated darkroom, and it takes time to light seal and prep my bathroom and once I do it's really cramped to work in. Not to mention the fact that no one else can use the bathroom while I'm working in it (my house only has one). Reverse processing takes less time for me than doing contact prints would, and uses half the film to boot.  

Quote

And who subjects a bunch of 'victims' to a slide show in a darkened room these days?

The mistake people make is showing pictures of themselves. If you're showing newlyweds pictures of their wedding or parents pictures of their kids I assure you they will sit through a whole carousel and beg  for more.

 

 

[JDMvW]

7 hours ago, AJG said:

There has never been a slide show that was too short.

Most people's experience, especially if you want people to appreciate them. Of course when I'm looking at them myself, I indulge

Minicam 1941-04

Edited November 30, 2022 by JDMvW

[JDMvW]

However, I will admit that some of my colleagues and students came to know me as the "Marquis de slides"

[glen_h]

18 hours ago, rodeo_joe1 said:

That's probably an Amidol-soda formula that was much-loved by reversal fans for the 2nd developer. It also had a following by those that liked a 'self-toned' print and didn't mind the darkly-stained fingers it gave as a side effect. 

It seems to use sodium dithionite. 

Unstable enough that it is flammable, and can ignite when damp.

It also warns that the powder can cause spots (fogging) on photographic materials,

so you should be careful not to spread it around the darkroom.

[rodeo_joe1]

5 hours ago, glen_h said:

It seems to use sodium dithionite. 

Yes, that's a chemical foggant that negates the use of a second exposure to white light. 

Most chemical foggants are toxic, or volatile, or both, and obviously they don't play nicely with unexposed film or paper.

I think the E4 process (IIRC) used a particularly nasty foggant chemical which was highly toxic and later banned from use. Probably why E4 was such a short-lived process. And whatever happened to E5??? 🤔

[glen_h]

27 minutes ago, rodeo_joe1 said:

Yes, that's a chemical foggant that negates the use of a second exposure to white light. 

Most chemical foggants are toxic, or volatile, or both, and obviously they don't play nicely with unexposed film or paper.

I think the E4 process (IIRC) used a particularly nasty foggant chemical which was highly toxic and later banned from use. Probably why E4 was such a short-lived process. And whatever happened to E5??? 🤔

The other part is 2-thio-barbituic acid.  The dithionite is definitely a reducing agent. I don't know about 2-thio-barbituic acid.

Besides, E-5, what about K-13, and many of the other K's.

And, for that matter, everything from C-23 to C-40.

 

[SCL]

Many years ago I used a product sold by Bessler called "slide-o-film" to produce slides from 35mm negatives. It was exceptionally low in ISO. With a negative abutted to the Slide-o-film, exposure in either a projector or exposed to the sun took about a minute. The SOF was then placed in water at its boiling point for development. The resulting image, unlike photographic films (black and clear) was milky white and clear. When projected the white obscured the light just as the black of negatives. There wasn't a lot of tonality, as I recall, but it was cheap, easy to use, and effective.