What did I do wrong with this B&W reversal?

Unbuiltbread · Oct 7, 2025

(http://imgur.com/a/H0PBFaW) Film was Rollei Retro 400
Process:
1. D76 1+1 for 35 mins
2. 250mL 3% hydrogen peroxide + 15mL White vinegar bleach for 7 minutes
3. Reexposure using a strong LED flashlight. Probably 3 passes over the length of film that took 30-45 seconds each. Holding the flashlight an inch or so away from the film.
4. D76 1+1 for 18 minutes (new chemistry).

Ignoring the minor uneven developing issues why did the positives come out so god damn dark? I feel like I over exposed the image on the reexposure after the bleaching. Maybe I should’ve held the flashlight further away and exposed it for less time. I got worried since so many people I’ve seen do this had problems with UNDER exposing during this step.

I developed for so long to ensure any exposed silver got developed, and then during the second development I followed the standard time for Rollei retro 400s.

Next time around I want to shoot the film at 75-100 ISO, develop like it was shot at 200ISO, and give it less light exposure but I want to make sure that is what I did wrong

dokko · Oct 7, 2025

looks to me that the main issues is incomplete bleach (very dark image despite long fist development plus solarisation).
I never used a hydrogen peroxide/vinegar bleach, I suspect it's not a vry reliable way of bleaching for reversal.

the other things hat look possibly problematic to me is using D-76 1+1 will give low contrast slides on normal film, the first developer time looks very long to me, and a flashlight on short distance seems more prone to unevenness than a larger light from further distance.

koraks · Oct 7, 2025

dokko said:
looks to me that the main issues is incomplete bleach (very dark image despite long fist development plus solarisation).
I never used a hydrogen peroxide/vinegar bleach, I suspect it's not a vry reliable way of bleaching for reversal.

Bingo.
Try a regular B&W bleach using permanganage or dichromate.

P C Headland · Oct 7, 2025

I thought LEDs were not a good light source (something to do with the spectral output?)

The peroxide bleach has worked fine when I've used it.

I tried Rollei Retro 400s (135) at EI200:
1. Develop in Rodinal 1+25 @23c for 15 minutes
2. Rinse / soak 10 minutes at 25c
3. Bleach @30c for 15 minutes
4. Re-expose 2-3 minutes
5. Re-develop in Rodinal 1+25 15 minutes
6. Rinse

dokko · Oct 7, 2025

P C Headland said:
I thought LEDs were not a good light source (something to do with the spectral output?)

not sure where this claim started, but I used LED film lights for re-exposure many times and never had problems.
thinking of it this way:
If LEDs wouldn't work properly for re-exposure, they wouldn't work proprly for the first camera exposure to start with, yet we all took plenty of photographs under LED lighting.

P C Headland said:
The peroxide bleach has worked fine when I've used it.

As said I have no experience with that bleach, but in the case above if it worked fine, then it would have bleached away the silver from the first exposure, thus there is no way the negative could be as dense (unless it was massively underexposed). bleach failure is pretty much the only explanation for the strange greenish color cast and and strange solarisation though.

getting good reversal results is challenging enough with a good bleach, so why use something experimental? Dichromate is pretty fool proof but has serious health and environment risks. So permanganate is the next best thing.

Raghu Kuvempunagar · Oct 7, 2025

As others have advised, use a proven bleach like Dichromate/Permanganate and a stronger first developer. Reversal processing is unfortunately a long and laborious process and there is no need to make it more painful by using suboptimal choices for bleach and first developer. If D-76 is all you have currently with you, you can make it more active by adding some Sodium Carbonate to it. If you search this forum for Hans F. Dietrich you will find an adaptation of D-76 for reversal.

thinkbrown · Oct 7, 2025

If you're averse to using dichromate/permanganate, there's an alternate bleach that's been published on photo that's peroxide/citric acid/edta based that's supposed to perform much better: https://www.photrio.com/forum/resou...ach-—-hydrogen-peroxide-edta-citric-acid.448/

Raghu Kuvempunagar · Oct 7, 2025

thinkbrown said:
If you're averse to using dichromate/permanganate, there's an alternate bleach

Copper Sulphate bleach works well on a variety of films and merits consideration though it adds additional steps to the process.

Bleach:

Water: 750ml

Copper Sulphate: 50g

Sodium Chloride: 50g

Sodium Bisulphate: 35g

Water to make: 1000ml

P C Headland · Oct 8, 2025

dokko said:
not sure where this claim started, but I used LED film lights for re-exposure many times and never had problems.
thinking of it this way:
If LEDs wouldn't work properly for re-exposure, they wouldn't work proprly for the first camera exposure to start with, yet we all took plenty of photographs under LED lighting.

Makes perfect sense!

dokko said:
As said I have no experience with that bleach, but in the case above if it worked fine, then it would have bleached away the silver from the first exposure, thus there is no way the negative could be as dense (unless it was massively underexposed). bleach failure is pretty much the only explanation for the strange greenish color cast and and strange solarisation though.

getting good reversal results is challenging enough with a good bleach, so why use something experimental? Dichromate is pretty fool proof but has serious health and environment risks. So permanganate is the next best thing.

In my case, I used the peroxide/vinegar bleach as that is what I could easily obtain, and it worked well for me. Depending on where you live, not all chemicals (or commercial products) are easy to obtain, so you work with what you've got.

Noted above the stronger developer - I used 1+20 for Rodinal and 1+30 for PC-TEA. I've also read a number of articles where people have recommended using paper developers, though I've not tried this.

isaac7 · Oct 8, 2025

What temperature was the bleach? One of those hydrogen peroxide bleaches need to be used at a higher temperature, 40c I think.

Samu · Oct 11, 2025

Raghu Kuvempunagar said:
As others have advised, use a proven bleach like Dichromate/Permanganate and a stronger first developer. Reversal processing is unfortunately a long and laborious process and there is no need to make it more painful by using suboptimal choices for bleach and first developer. If D-76 is all you have currently with you, you can make it more active by adding some Sodium Carbonate to it. If you search this forum for Hans F. Dietrich you will find an adaptation of D-76 for reversal.

It often is, because there are strict restrictions in many countries in obtaining sulfuric acid, potassium dichromate, and even potassium permanganate, which has been classified as a drug precursor. Some people cook amphetamines using this, and the governments react by banning the chemicals altogether.

Raghu Kuvempunagar · Oct 11, 2025

Samu said:
It often is, because there are strict restrictions in many countries in obtaining sulfuric acid, potassium dichromate, and even potassium permanganate, which has been classified as a drug precursor. Some people cook amphetamines using this, and the governments react by banning the chemicals altogether.

No doubt availability of chemicals needed for reversal processing v:aries across geographies, but OP seems to be from USA and shouldn't have much of a problem.

1957ExaktaVarexIIa · Oct 12, 2025

As it has been written already...

dokko said:
looks to me that the main issues is incomplete bleach (very dark image despite long fist development plus solarisation).

Yes - I think that's absolutely right.
Just to demonstrate the effect dokko mentioned:

dokko said:
the other things hat look possibly problematic to me is using D-76 1+1 will give low contrast slides on normal film, the first developer time looks very long to me, and a flashlight on short distance seems more prone to unevenness than a larger light from further distance.

I agree.

As for the developer: When I started reversal process I got the advice to use a strong first developer, back then it was Tetenal Dokumol which has always worked fine for me.

Today Ilford PQ Universal should work well. As soon as my remaining Dokumol stock is consumed, I think I'll switch over to PQ.

dokko said:
getting good reversal results is challenging enough with a good bleach, so why use something experimental? Dichromate is pretty fool proof but has serious health and environment risks. So permanganate is the next best thing.

Moreover it's easy to check the bleaching even during the process itself: I use to use permanganate with sulfuric acid.

Standard bleaching time: 5 min.
After those 5 min. I open the tank and look at the film while keeping the bleaching bath inside the tank. Sure, it differs from one emulsion to another how a bleached film looks like: Fomapan R100 should be bright yellow. Same, as far as I remember, with Rollei Infrared 400 and old (! 2007) Agfapan APX 100. Fomapan 400 is light grey. Similar with Kodak Tri-X Pan.
There should not be any dark brown areas left on the film. These indicate that bleaching has not yet been finished.
If I see those dark brown areas I continue bleaching for 3 or 4 minutes and check again.
If there are still dark brown areas I set up a new bleaching bath and bleach for another 3-5 minutes.

flavio81 · Oct 13, 2025

I'm an armchair specialist of this process, but I can contribute:

Unbuiltbread said:
(http://imgur.com/a/H0PBFaW) Film was Rollei Retro 400
Process:
1. D76 1+1 for 35 mins

D76 gives too low contrast, although 35 minutes should (?) pump the contrast.
Still i have never seen D76 used as first developer for reversal. Get Dektol or paper developer to pump up the contrast.

Unbuiltbread said:
2. 250mL 3% hydrogen peroxide + 15mL White vinegar bleach for 7 minutes

3% (10 volume) H2O2 is very weak. 7 minutes will not be enough at all to bleach. I think here is the biggest mistake and sadly i haven't found a reliable guideline on this part, but when I tried 30 volume H2O2 to bleach an unexposed silver strip, it seemed to require more than 20 minutes.

Unbuiltbread said:
Ignoring the minor uneven developing issues why did the positives come out so god damn dark?

Dark is usually not enough bleach and/or not enough first development.

flavio81 · Oct 13, 2025

koraks said:
Bingo.
Try a regular B&W bleach using permanganage or dichromate.

Permanganate is hard to get here.

Dichromate, even harder, and is toxic stuff.

P C Headland said:
The peroxide bleach has worked fine when I've used it.

3. Bleach @30c for 15 minutes

Which concentration of hydrogen peroxide were you using?

Ivo Stunga · Oct 14, 2025

flavio81 said:
Permanganate is hard to get here.

You can try your local water ion exchange filter supplier as it's used to purify water and gets dumped down the drain whilst doing so

P C Headland · Oct 14, 2025

flavio81 said:
...

Which concentration of hydrogen peroxide were you using?

3% concentration.

Because we had such a spring-like weekend (gale force winds, rain, low cloud....) I thought I may as well do another reversal experiment. Inside!

Since we were in the clouds, there wasn't much natural light. Wanting to keep the shutter speeds repeatable meant the aperture was a bit wider than ideal for focus, but exposure wise it worked OK (slowest shutter was 1 second). Film was Fomapan 100 shot at 100.

I shot metered (camera + light meter in agreement), 0, -1, -2, +1, +2, +3

1. 1st developer: PC-TEA 1+25 @ 25C (saved for use as 2nd developer) for 15 minutes
2. Rinse a couple of times (bringing temperature up to 30C)
3. Bleach 30 minutes at 30C (350ml hydrogen peroxide plus 21ml white vinegar)
4. Reexposure (on reel)
5. 2nd developer: PC-TEA 1+25 @ 25C (re-used from 1st developer) for 15 minutes
6. Fix (probably not necessary?)
7. Wash

Here's an iPhone shot with the postives on a light box. For scanning, +1 looks best, box speed looked like it should project OK though.

When the weather next co-operates I'll shoot some outside test scenes and try the same process again.

YoIaMoNwater · Oct 14, 2025

P C Headland said:
3% concentration.

Because we had such a spring-like weekend (gale force winds, rain, low cloud....) I thought I may as well do another reversal experiment. Inside!

Since we were in the clouds, there wasn't much natural light. Wanting to keep the shutter speeds repeatable meant the aperture was a bit wider than ideal for focus, but exposure wise it worked OK (slowest shutter was 1 second). Film was Fomapan 100 shot at 100.

I shot metered (camera + light meter in agreement), 0, -1, -2, +1, +2, +3

1. 1st developer: PC-TEA 1+25 @ 25C (saved for use as 2nd developer) for 15 minutes
2. Rinse a couple of times (bringing temperature up to 30C)
3. Bleach 30 minutes at 30C (350ml hydrogen peroxide plus 21ml white vinegar)
4. Reexposure (on reel)
5. 2nd developer: PC-TEA 1+25 @ 25C (re-used from 1st developer) for 15 minutes
6. Fix (probably not necessary?)
7. Wash

Here's an iPhone shot with the postives on a light box. For scanning, +1 looks best, box speed looked like it should project OK though.View attachment 409378

When the weather next co-operates I'll shoot some outside test scenes and try the same process again.

This looks pretty good!

isaac7 · Oct 14, 2025

P C Headland said:
3% concentration.

Because we had such a spring-like weekend (gale force winds, rain, low cloud....) I thought I may as well do another reversal experiment. Inside!

Since we were in the clouds, there wasn't much natural light. Wanting to keep the shutter speeds repeatable meant the aperture was a bit wider than ideal for focus, but exposure wise it worked OK (slowest shutter was 1 second). Film was Fomapan 100 shot at 100.

I shot metered (camera + light meter in agreement), 0, -1, -2, +1, +2, +3

1. 1st developer: PC-TEA 1+25 @ 25C (saved for use as 2nd developer) for 15 minutes
2. Rinse a couple of times (bringing temperature up to 30C)
3. Bleach 30 minutes at 30C (350ml hydrogen peroxide plus 21ml white vinegar)
4. Reexposure (on reel)
5. 2nd developer: PC-TEA 1+25 @ 25C (re-used from 1st developer) for 15 minutes
6. Fix (probably not necessary?)
7. Wash

Here's an iPhone shot with the postives on a light box. For scanning, +1 looks best, box speed looked like it should project OK though.View attachment 409378

When the weather next co-operates I'll shoot some outside test scenes and try the same process again.

Looks good but man, half an hour in the bleach? This article says that if you run it at 40 it would only Take 10 minutes.

Black and White Reversal with Hydrogen Peroxide and Vinegar

Have you ever wanted to develop your own black and white slides? Traditionally there were two ways to show your photography: print and projection. We now often just scan for the Internet, but there is something pretty great about projecting your images. Even if you still just want to scan them...

imager.ie

He also says that you can watch after 5 minutes to get a better idea of exact timing.

P C Headland · Oct 14, 2025

isaac7 said:
Looks good but man, half an hour in the bleach? This article says that if you run it at 40 it would only Take 10 minutes.

Yeah, could probably half that (previously I'd done 15 minutes), but since (AIUI) you can't over do it, why not. Not like I was in a rush to get outside.

flavio81 · Oct 15, 2025

P C Headland said:
Film was Fomapan 100 shot at 100.

Fomapan 100 is said to be unsuitable for reversal. And it has a very dense base, not good. Foma make R100 which is specific for reversal.

I would suggest trying first with Ilford FP4 or HP5.

koraks · Oct 15, 2025

flavio81 said:
Fomapan 100 is said to be unsuitable for reversal.

OK.

Fomapan 100.
Contrast control wasn't super-duper. That's because I did this one sheet for fun and basically winged all aspects of it; exposure, 1st dev, etc. I recall the bleach involved a cleaning product from a local drugstore.
No doubt one could optimize it. I just thought 'neat' and moved on.

It is correct that the base on the 135 version is tinted. Some people may find this to be an issue. Some won't. It's not a particularly dark base, or strongly tinted.

I bet @Ivo Stunga has tried reversal processing F100. He's put a heck of a lot more time into this than I ever have.

isaac7 · Oct 15, 2025

P C Headland said:
Yeah, could probably half that (previously I'd done 15 minutes), but since (AIUI) you can't over do it, why not. Not like I was in a rush to get outside.

I guess I’m just impatient lol. I guess the E-6 process takes a while too. That article does make it sound like getting the 40 degrees is kind of a pain. So maybe 30 minutes isn’t too bad if it is noticeably easier to do.

P C Headland · Oct 15, 2025

flavio81 said:
Fomapan 100 is said to be unsuitable for reversal. And it has a very dense base, not good. Foma make R100 which is specific for reversal.

I would suggest trying first with Ilford FP4 or HP5.

My examples with pictures, would suggest otherwise. Not perfect, but perfectly usable for what I'm doing, and it's what I had available.

I've not found too much difference in base between Fomapan 100 and the Ilford films. The clearest base I've seen is Rollei Superpan 200 and Adox HR50. I don't have ready access to R100. I do have a few rolls of expired Scala (120) which I may try once I'm happy with the process.

Raghu Kuvempunagar · Oct 15, 2025

koraks said:
Fomapan 100.
Contrast control wasn't super-duper. That's because I did this one sheet for fun and basically winged all aspects of it; exposure, 1st dev, etc. I recall the bleach involved a cleaning product from a local drugstore.
No doubt one could optimize it. I just thought 'neat' and moved on.

It is correct that the base on the 135 version is tinted. Some people may find this to be an issue. Some won't. It's not a particularly dark base, or strongly tinted.

I bet @Ivo Stunga has tried reversal processing F100. He's put a heck of a lot more time into this than I ever have.

All films can be reversed and some give better results than other. However, some films couldn't be run through the vastly famous Dr5 process and hence might have wrongly earned the reputation of being unsuitable for reversal.

From https://www.dr5.com/blackandwhiteslide/filmreviewdev1.html

The following below films are not recommended or CANNOT be run through the dr5-process:
FOMAPAN-100 & 400 • ALL SHANGHI • FUJI-ACROS100 • COPEX/ADOX-20
APX-400 & 25 • ALL C41-XP2

What did I do wrong with this B&W reversal?

Unbuiltbread

dokko

koraks

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P C Headland

dokko

Raghu Kuvempunagar

thinkbrown

Raghu Kuvempunagar

P C Headland

isaac7

Samu

Raghu Kuvempunagar

1957ExaktaVarexIIa

flavio81

flavio81

Ivo Stunga

P C Headland

YoIaMoNwater

isaac7

Black and White Reversal with Hydrogen Peroxide and Vinegar

P C Headland

flavio81

koraks

Moderator

isaac7

P C Headland

Raghu Kuvempunagar

What did I do wrong with this B&W reversal?

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