If you just want to play with the process, have at it. If you want B&W positives, like slides for projection, you can shoot normal negatives on whatever film you like, contract print them on litho film, and develop that litho in Dektol/D-72 for a more controlled result with less messing around. The huge advantage is that you still have your negative available for more traditional uses. I suspect that this is also quicker and cheaper.

For those who don't mind going a little off program, it's possible to make a reversal bleach with copper sulfate (available in home improvement stores, sold for removing roots in drain pipes) with a little table salt added; this converts the developed silver to silver chloride -- but little if any of the original halide is this variety, and a bath in ammonium hydroxide ("clear ammonia" from the cleaning supplies aisle of the supermarket) will dissolve this halide and not the ones we want to expose before the second developer. The advantage is that, unlike permanganate, this not only doesn't stain (and doesn't require handling sulfuric acid; while it does need to be acidic, citric acid or acetic acid are sufficient as we only need to control pH rather than provide a reservoir of sulfate ions in solution), it doesn't soften the emulsion and make it prone to easy damage, or even to peeling off the film base (that's the permanganate bleach doing that, not the second developer). When I've done reversal in the past, however, I used potassium dichromate. I don't recommend this if there's an alternative available; not only is the dichromate toxic and probably carcinogenic, you still have to handle sulfuric acid (dichromate, like permanganate, works by converting the developed silver to soluble silver sulfate, but hardens the gelatin rather than softening it). When I've done this (only a couple times) I took the "too light" final image to indicate I needed to expose less; I was using Tri-X, and found the best exposures at EI 640-800, or 2/3 to 1 stop gain in film speed. My contrast looked normal (to my eye), so I felt exposing less was preferable over shortening the first developer time. I would differ with your statement relative to fixing: the original negative image is *not* still present to be fixed away; that silver was dissolved in the bleach step, not converted to something fixer can remove. It does no harm to fix after second developer, but if you've developed to completion in that step, fixing is technically unnecessary (the technical minded could confirm this by using fresh fixer after second developer, then performing a silver content test on the fixer that was used -- it should show no fixed-out silver complex). While I agree that in our post-projector age, there aren't many uses for B&W film positives (and if you're going to project these, you'd want to use the actual projector, screen, and room lighting you're working toward to confirm exposure and first developer time), I can see one place this process is very practical: if you shoot your original exposure on printing paper, this process will let you get a one-of-a-kind positive print without the expense of Harman Direct Positive paper (plus you can use multi-contrast filters to control your final contrast). You'll need to adjust first developer time, of course, but on the other hand, you can do the first developer and bleach steps under your regular printing safelight.

Hello there! Been reversing since 2016 with great results. Here are some tips to improve your results: 1:21, 5:12 - many films - especially classic emulsions - are absolutely best left without it, 0 grams. Hence your overdevelopment at 17:04 and poor density; 2:38 - try diluting this bleach by doing 1A+1B+1Water. Safer for emulsion, saves chems and bleaching time stays the same. 300ml per 35mm film in Paterson; 3:24 - you can try redevelopment in first developer, have had only good results and saves developer. And capacity is about 3 films, third might require +1min; 4:20 - Fomapan makes a kit for their reversal film - Fomapan R 100, haven't tried on other films, because Ilford's recipe just works for me; 6:23 - agitation has a strong impact. Extreme example: Stand Vs Constant. 3 inversions in 90s will give extended shadow and highlight detail, for example; 10:01 - it's the Bleach that makes emulsion soft. Hence I recommended using dilute - Foma films will be thankful; 18:26 - I'd say we need to work on which film needs what amount of hypo - if any. And then we can experiment Pushing/Pulling films to their best! 22:24 - guys, get a slide projector - that'll tell you all :) And slides scan good too: www.flickr.com/search/?sort=date-taken-desc&safe_search=1&tags=ilfordreversalrecipe&user_id=108634366%40N07&view_all=1 When it's a film I haven't reversed yet, I start 12min reversal with 3 inversions every 90s (Paterson tank) without any hypo, evaluate dry slides and go from there, adding hypo in 0.5g increments if 12min development didn't develop things enough. Or 1g increments with modern emulsions. 1x135 film gives 4 good length strips for 4 different development tests. Takes patience and time, but you can nail shit down this way, be on a solid ground ISO-wise, be literate in Pushing and Pulling slides. Speedy recovery!

Hoping for a speedy recovery for you and yours. Thanks for what you do! I think this is a good time to buy some merchandise:) I caught up on re-architecting and organizing my digital storage when I was sick. Take care!

Thanks for sharing the process!!

Hope everyone recovers well. Thanks for the video.

Another great video! Hope you all feel better soon. Interesting that tmx appears to gain speed in the reversal process. I will be trying this to make slides to project.

Great video and explanation of the process! I could see something like this working well with overlapping them like transparencies. I'm sorry that it wasn't just the images that were positive. Wishing everyone a speedy recovery.

Kudos to you for going the H2SO4 route. That's kinda scary. There is a H2O2 process floating around that seems a lot less intimidating. Ilford XP2 will also make lovely monochrome positives when run thru E-6 chemistry. Over expose two stops, over develop (1st dev) 25%.

Thanks for another interesting and useful video! I have done some experiments with the Ilford process and I am surprised that my end goal wasn't one you mentioned. I mount the results as 35mm slides and project them. It's a wholly different way of viewing a photograph as compared with backlighting a positive (quite similar to viewing a scan on a backlit computer screen) or printing on paper from a negative and viewing by reflected light. Old 35mm slide projectors are really really cheap and you just need some even white surface for a screen. I bought a very cheap plain white roller blind for this purpose. Sitting in a darkened room and projecting your photos to images several feet across is to my mind really quite magical. I bet your kids would love it!

Hope you and your family recover quickly. I have been careful enough so far to where it has spared me. #hermitlife

I believe you are correct by wanting to adjust your ISO, back in the old days we would underexpose Kodachrome (K25) by 1/3 to 1/2 stop to obtain better saturation. Thank you for all the effort you put into these presentations.

Very cool! Thanks for sharing the Ilford reversal process. I don't have any useful firsthand experience with B&W reversal, but from what I gather Foma 100 might not be ideal for high Dmax, per the folks who run the dr5 process. Great video nevertheless (esp. the tank agitation time-lapse), and it's cool to see the positive image on the light table!

This is a process I have in mind to try for many many years, but to be honest I never found any good reason to use it (aside from experimenting). So I appreciate a lot that you share with us your experience with this process. Probably I will try it to apply on a project I have in mind, unless I decide to use a 45,7m can I got of Kodak Rapid Process Copy Film (a very estranged film that get positive with “normal” proccess).

get well soon

Love this, considering making 10x8 sheet-film anthotypes without any digital intervention, so may try.

Did you see Analog Resurgence’s B&W Reversal video? His process uses HC-110+Ammonia+Fixer for first developer and Iron Out for Chemical Fogging & Reversal Developer.

Thanks for the video. I was thinking about how to create positive film images on medium format film negative to create larger negatives for contact prints 😁

I love this process. I love using it to create a 4x5 "original piece," and my super slide projector is on its way from eBay for my 6x6 slides.😁

I've been playing with this process for a few months, since seeing this video originally. A couple of comments. First, I just tried my first roll of FP4+ in 120 roll film format and at the final fix stage the emulsion mostly came right off the base. It seemed fine up to that point. There are faint images still visible. Oddly, FP4+ worked fine in 35mm. I checked with Ilford and indeed the two sizes use different thickness plastic and some differences in the coatings. PanF50 worked ok for one roll of 120 that I tried, am going to keep trying with that. I may try TMax100 since it seemed to be ok for you. I may also try using weaker fix at the final step, as most if not all of the silver should be developed by then at either the first or second step. I am doing this to make stereo slide pairs for viewing with a stereo viewer, using a Sputnik 6x6 stereo camera and a viewer made with 3d printing by Oszko in Germany. Pentax has a neat gadget, a beam splitter that fits over their standard 50mm K mount lens, going on any 35mm Pentax SLR, and then viewed with a Pentax slide viewer. However this splits a single 35mm frame to two vertical halves, so pretty tight real estate versus the 6x6. The Sputnik is not a fun camera to get working, but it's pretty much the only medium format stereo option (there was a Rolleiflex but I guess only a few got made as it's either un-findable or way overpriced, similarly a Chinese medium format stereo camera that pops up on google searches but also not really available). Thanks again! (p.s. I am also doing color slides by E-6 chemistry for the same project, but currently Fujifilm is not making 120 slide film at all, and Kodak has jacked the price of Ektachrome to the stratosphere.

Thanks. I've been curious about black and white reversal since I want to project some black and white slides. it may be something I'll have to do myself.

Hi Mr Naked and thank you for this very well done Video! I think, it is nothing mor but a verbal error of yours .... but .... it takes 33ml of battery acid to make 1 liter of bleach and not 10 ml as you claim! Battery acid is concentrated to 37% sulphoric acid and that makes 33ml then. Indeed ..... the ILFORD REVERSAL PROCESS works very well with FOMA 100 Film! Yours from Germany Klaus Rickert

Great video, thanks. It's Exposure Index, not the ISO, btw.

Thanks for your video! Just a quick question, when you do 2nd exposure on 120 rolls, do you take the film off the reel?

Here in Europe you can get 3 ready made reversal kits. Adox Scala, Rollei Dia kit and foma does a kit as well. I tried my luck with Rollei Retro 400s with the Adox Scala kit. Unfortunately I didn't not bleach long enough so I got a grey fog in the highlights.

Thank you, this is really cool to see in action. It's something I have wanted to try forever but always been too intimidated. Regarding the emulsion, is there some sort of hardener you could add to prevent the emulsion sliding off?

Foma also makes a BW reversal kit. You can get it freestyle.

Adox Scala should be available via Freestyle. Also Adox CHS in sheets should work great since it has a clear base

Question. Have you tried the RA-4 reverse, there is a few videos about it but most seem to be about using paper on large format cameras, I was thinking it would be a good way to print slides. I am thinking on trying it out myself for some of my slides, scanning slides just seems to defeat the purpose of shooting film. Scanning a print is a whole other story. Any thoughts on it? I think it would make a great video and the lights on second development just seems magical to me. Thank you.

Does anybody print from negatives onto sheet film, develop the sheet film as positives, then display the film positives in light boxes?

Questions! If you do this in a Paterson style tank will the sulfuric acid and potassium permanganate damage the plastic tank? Or worse, the metal balls on the reel? Also, I guess that you should be able with some experimentation to substitute other developers for the first step, right?

Hey just tell the kids it's an NFT from the 1890's and you're sitting on a gold mine!

Hey! What roller are you using to your tank?

What kind of witchcraft is this!!! Great video and concise explanation. 🙂

Can you use potassium meta bisulfate as a clearing agent, instead of sodium meta bisuflate?

Can anyone point me to LF bw films that are coated on a crystal clear support? If I want slides, I hate grey or blueish support.

Does this work for paper using black and white slides? I've got a TON of old 35mm positive slides I got from my grandparents