Black and white reversal processing?

John Wiegerink

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I have just a quick question about making slides out of b&w negative films and didn't want to barge into a thread about it that is already out there. My question is what is the purpose or the benefit over just processing as a negative. Yes, I already know about viewing ease, whether on a light table or slide screen via projector. I was wondering if there was something else I'm missing since there seems to be a little increase here on the subject. Do they scan easier or better? What am I missing. Just a quick answer and to satisfy my curiosity. Thanks!
 

Ian Grant

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Many years ago, probably 1973, I went to a student union photo club lecture on reversal processing. The student giving the lecture was doing post graduate reseach, funded by Kodak.

First B&W reversal processed slides have finer grain and a far longer tonal range, his images were stunning. He then showed B&W reversal prints made from similar B&W slides, again superb, he was using FP4 and Ilfobrom paper. However, he explained the downside was how difficult making the prints was, as it was extremely time-consuming. Even test strips took time because Ilfobrom paper was fibre based, so washing out the reversal bleach took quite a few minutes. Then matching paper grade to the chosen slides and exposure. There were no RC/PE papers in 1973.

Back then, there was 35mm Positive film for making B&W slides from negatives, very slow but extremely fine grain, it was only blue sensitive so could be handled with a normal B&W paper safelight, and processed in paper developer.

Ian
 

loccdor

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Other than what's been mentioned, the scans would require less contrast adjustment as they would already be at or near the levels intended for viewing, where as with negative a contrast curve normally is applied. Stray light reflections in a DSLR digitization setup are also more of a problem for lower contrast film than high, because the stray light gets amplified by the contrast enhancements.

Dust will also show up as black instead of white on the final image. Bright white dust is more distracting.
 

Nicholas Lindan

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Another advantage to processing 35mm as a positive is the ease of making enlarged negatives for alt. process. I find it easier than reversal processing of an enlargement from a 'negative' negative.
 

runswithsizzers

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John Wiegerink said:
Do they scan easier or better?
Click to expand...
If you are using a budget film scanner, in some cases, you may run into problems with shadow detail when scanning slides. That is, your eye may be able to see faint shadow details which the scanner may have trouble differentiating from noise. If the scanner manufacturer's specifications are to be trusted (;-), the scanners with a higher D-Max number should be able to read deeper into the shadows.

On the one hand, post processing b&w scans is slightly easier because you can skip the reversal step, and unlike negatives, the whole process is intended to produce a viewable result. So the need for contrast/gamma adjustments should be less. On the other hand, the half-dozen rolls of b&w film which I had processed as positives were all somewhat high in contrast which made recovery of any marginal shadow/highlight details more difficult.

Mine were all processed by DR5. I have no idea how his processing compares to what else is available for reversal processing, and whether contrast I saw was due to his process, or if that is just the nature of reversal processing. If you are doing your own processing, I assume you may have some control over contrast(?) so maybe not a significant issue(?)

If shooting in contrasty light, you will probably want to try to control your exposures a little more carefully than what most people consider necessary for negative film. Also, in some cases the recommended EI for reversal processing may be different from what you might choose for negatives.
 

Alessandro Serrao

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A b&w slide has qualities radically different than a negative.
First of all, due to the peculiar way of developing it, a b&w positive has way less grain than a negative and the grain where present are always much smaller and compact.
Then, all b/w slides has a glowing auras around black/white transitions, which gives you a sort of a "dreamy" effect. It's somewhat subtle but there is.
A b&w slide is always archivial no matter what.
The tonal scale is longer and rendition is much more different.
All in all a b&w slide is better in every respect than a negative counterpart.
A plus: you don't have to pay ridiculous prices for print paper...
 
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John Wiegerink

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So, from what I have gathered reading all this I'd say the only advantage is in direct viewing/projection. There is no advantage with scanning or printing at all?
 

Ian Grant

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John Wiegerink said:
So, from what I have gathered reading all this I'd say the only advantage is in direct viewing/projection. There is no advantage with scanning or printing at all?
Click to expand...

There may be some advantages for scanning. There was a Scottish member here who had his 120 negatives reversal processed and scanned at the same time and the results were superb, he's not posted here for quite a few years.

Ian
 

Alessandro Serrao

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John Wiegerink said:
So, from what I have gathered reading all this I'd say the only advantage is in direct viewing/projection. There is no advantage with scanning or printing at all?
Click to expand...

In printing no, of course because you have to do an internegative. Every step has a quality loss.
In scanning yes, as Ian has said. The b&w slides retain all its advantages provided you use a hi-end scanner...
 

ChrisGalway

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If you enjoy processing your own B&W films here's another advantage of processing direct reversal: when you've completed the process, open the tank and removed the processed film from the spiral, you see these beautiful beautiful vibrant transparencies, as positives, not indecipherable negatives!!!

It's a wonderful experience.

(I process reversal for direct viewing of stereo pairs in an optical viewer ... why ruin everything by going digital?)
 

MattKing

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Alessandro Serrao said:
In printing no, of course because you have to do an internegative. Every step has a quality loss.
In scanning yes, as Ian has said. The b&w slides retain all its advantages provided you use a hi-end scanner...
Click to expand...
In post #5 Nicholas points out a really big advantage for those who make contact prints using Alternative Processes.
Nicholas Lindan said:
Another advantage to processing 35mm as a positive is the ease of making enlarged negatives for alt. process. I find it easier than reversal processing of an enlargement from a 'negative' negative.
Click to expand...
 

koraks

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MattKing said:
a really big advantage for those who make contact prints using Alternative Processes.
Click to expand...

Is it? For alt processes, you could just as well start with a normal negative, then enlarge that onto Ortho film and reversal process it. It'll be just as much work as starting with a reversal processed slide and making an internegative from that. The main difference is that if you start with a regular negative, you can also enlarge that to normal printing paper, so it's ultimately more flexible. So I don't really see a clear advantage here. It's a valid approach, but not inherently superior to any alternative.

Not to mention that 95% of the people doing alt processes use inkjet negatives these days (queue the 5% who don't - yes, we exist, but that doesn't change anything about the majority).
 

MCB18

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I’m currently experimenting with a roll of direct positive, I might try doing some more tests tonight, 0.05 ISO could be a good EI. But seeing 120 positives without having to bleach and second dev, that is extremely annoying to do. Seeing a positive image coming out of the tank is just magical! Was told alt process folks might enjoy it as well
 

Alessandro Serrao

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There's a big caveat when doing reversals: the lack of slide mounts. Nobody seems to make them anymore...
 

loccdor

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The Korean company Matin makes glassless plastic slide mounts that you can find on Amazon.
 

dynachrome

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Years ago I used Panatomic-X rated at ASA 80 and developed it in the Kodak Direct Positive kit. If you look for it, I think you can find the formulas for all of the steps. Kodak did make Direct Positive film which had an ASA of 100. It's main advantage was that it had a clear base, which Panatomic-X did not. How good were my slides? They were very nice. I used heat seal slide mounts and my mother's iron. If I could get Panatomic-X and a Direct Positive kit, I would try it again.
 

Yezishu

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My thought is that in the past, negatives were more useful because they could be easily enlarged and printed on paper using optical methods. However, the situation has now reversed; the primary way of viewing images is through scanning and digital display rather than physical photo. The main disadvantage of slides has disappeared, leading to increased interest in them.
 
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John Wiegerink

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I was thing the same, but processing in also a little more involved with transparency/slides. I have two nice 35mm stereo cameras, viewers and complete Realist slide mounting kit. I just might try my hand at processing a few rolls as B&W slides to see the results. Who knows, I might just like it?
 

Romanko

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Do you need to use a special reversal film like Fomapan R or Adox Scala 50 or any film would do.
Also, what makes these reversal films special?

Sorry if I deviate from the main subject of the thread but it is kind of related to the question of why would one use it. For me, being limited to just two (slow speed) film stocks seems like a huge disadvantage.
 

koraks

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John Wiegerink said:
I have two nice 35mm stereo cameras
Click to expand...

That is one application where slides really work magnificently. Give it a try.

Romanko said:
Also, what makes these reversal films special?
Click to expand...
Clear base mostly. You can reversal process other films, too. Many films have a tinted base, which makes the results a little less spectacular.
 

Ivo Stunga

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Romanko said:
Do you need to use a special reversal film like Fomapan R or Adox Scala 50 or any film would do.
Also, what makes these reversal films special?
Click to expand...

Clear base makes slides that pop. Clear bases in 135 are quite rare and often is a strong indicator of a respooled Aerial film. Fomapan R100 and Adox CHS 100II might be the sole 135 films with clear Triactate base to my knowledge.
Other clear 135 films tend to be respooled AgfaPhoto Aviphot 80 and 200 with PET base, and most common examples are: Adox Scala 50 / HR-50, Rollei RPX25, Retro 80S, Retro 400S, Superpan 200 and Infrared 400.
But in larger formats clear base is quite common, making these a good choice for reversal.

I'm shooting slides exclusively for projection and am enjoying the challenge, rendering, reduced grain and ability to project at cinematic sizes very much. Slides also are 1st gen analog product, meaning no loss of anything via transfer to paper or screen via scan.
 
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Ivo Stunga

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runswithsizzers said:
Mine were all processed by DR5. I have no idea how his processing compares to what else is available for reversal processing, and whether contrast I saw was due to his process, or if that is just the nature of reversal processing.
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Contrast can be controlled at 1st development stage - just like with negs. Developer dilution, development times and agitation frequency have impact on contrast. One isn't forced to stick to a defined contrast grade when doing slides. You can also push and pull BW slides. If DR5 produced a single contrast grade and asked to shoot any given film at specific EI to boot - then I question such an approach. Hard.

runswithsizzers said:
Also, in some cases the recommended EI for reversal processing may be different from what you might choose for negatives.
Click to expand...
Not necessarily. See my comment/reply just above. Actually I'm quite triggered by the mythos of "you have to shoot film X at EI X to be compatible with our services". There's no valid reason for that with DIY BW Reversal kits - like Ilford Reversal Processing recipe. Imagine negatives having such dumb requirements. Unprofessionalism vibes detected... With commercial kits you can also have different dilutions, agitation frequencies and boosters - adding some hypo crystals to developer will make it more active, for example. So I see no valid reason for that circus.

Alessandro Serrao said:
There's a big caveat when doing reversals: the lack of slide mounts. Nobody seems to make them anymore...
Click to expand...
Nobody is really making film cameras anymore, so we buy used and/or stock made in the past. Slide mounts are no different.

See these eBay links for examples:

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Get the best deals for Film Slide Mounts at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items!
www.ebay.com

Diarahmen for sale | eBay

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Europan

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Reverse processing about doubles film speed. That is to say that true reversal films, such that consist of two different emulsions mixed together (a higher speed mostly panchromatic and an unsensitised low speed one) are actually of half box speed. Example: Fomapan R(eversal) 100 is in fact an ISO 50 material. The gain in speed comes inherently from the reversal process.

Reverse treatment always yields a little less maximum density as well as a little less differentiated lights but when thoroughly done slides (or cine films) can show brilliance and stark black.

It’s the decision what type of original you want, a negative or a positive. Keep in mind that you can make nice projection positives from a negative. That’s how cinema works. Home cinema is rather based on reversal originals. Colour TV films were and still are reversal stocks such as Ektachrome. You can project Ektachrome, it is designed for that. Kodachrome was somewhat more contrasty. With black and white you’re free to manipulate the image character in any direction. Limit is the availability of film stocks.


To reverse process a common film I call untrue reversal. You can run into a coloured film base (anti-halo countermeasure), too thin shadows due to a not so silver rich emulsion, harsh contrast, and more.

Bergger sells a print film of interesting properties.
 

runswithsizzers

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Ivo Stunga said:
If DR5 produced a single contrast grade and asked to shoot any given film at specific EI to boot - then I question such an approach. Hard.
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Based on my very limited experience with DR5, I would say their management philosophy was definitely different from most other commercial labs. "Unprofessional vibes" is as good a description as any. But for whatever reasons, DR5 is no more. And as far as I know, presently there is nowhere in the USA to send b&w stills film for reversal processing(?) So if the goal is to promote reversal processing of b&w film, was DR5 better than nothing? For me it was not -- after a very unpleasant email exchange with the owner, I refused to give him any more of my business.

If there was a decent commercial lab in the US where I could send a few rolls per year for b&w reversal processing, I would definitely be doing that. But I can't quite convince myself that I want to try reversal processing at home. As someone who shoots about 20 rolls of b&w film per year, I sometimes find my myself wasting chemistry because I can't use it up before the chemistry expires. Adding another set of chemistry for reversal processing to my basement shelves would probably mean even more chemistry wasted for me. On the other hand, if I switched to reversal processing, exclusively, then I would probably be no worse off than I am now, so something to consider.
 
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