Author Topic: b&w reversal (Read 16723 times)

Benjamin J · « **on:** October 24, 2011, 01:08:02 AM »

so a friend of mine is asking me to do some super 8 processing for a film he's making. i haven't done b&w reversal since i graduated, and am running into issues tracking down bleach. kodak only offers 20 gallon batches (which i find somewhat excessive), and while i would be comfortable mixing my own, the prospect of working with 98% sulfuric acid seems, well.... annoying. the formulary sells tmax reversal kits but he'll be shooting on tri-x; would these be incompatible?? If this is a dumb question, please forgive me for being an ilford user.

i realize this is a cine question, but film is film. i've done e6 in my lomo tank many times, and would otherwise use D19 for b&w cine film.

Mojave · « **Reply #1 on:** October 24, 2011, 01:18:45 AM »

This question is quite beyond me. Good luck on getting it figured out!

LeonY · « **Reply #2 on:** October 24, 2011, 04:04:32 AM »

Benj, I ran into a similar problem a few years ago, trying to develop double 8mm bw reversal....in In Australia and no one was willing to sell me the bleach, couldn't even get Kodak to sell me a tank of the stuff unless i was some sort of huge company!

I went don the road of mixing it myself, but when i had to purchase the acid, i stooped and said 'yeah na'. Had to just send the stuff off to the 1 and only place i knew of in Victoria that developed reversal. I dont think the Tri-x kits will work...but i could be totaly wrong..

I gave up on doing this stuff myself after i found out how hard it was to find basic chems.

Francois · « **Reply #3 on:** October 24, 2011, 03:48:49 PM »

Well, I personally doubt it wouldn't work.
I checked various formulas in my own formulary and they're all pretty similar.

We should ask Terry on this one since he's our Cine guy...

Bastian · « **Reply #4 on:** October 24, 2011, 04:15:26 PM »

I'd say bleach is bleach. You may have to experiment with the bleaching times, because the different silver content of Tri-X compared to Tmax. But it can't be a big issue.
I sometimes shoot some B/W reversal films in 35mm format. I use the Kit made by Foma and the Fomapan 100R. The Foma Kit could be a bit cheaper than the Kodak Stuff ( and the Kodak Kit is banned here in Germany because it has a potassium dichromate based bleach). The process isn't much more complicated than the normal B/W process.

Terry · « **Reply #5 on:** October 25, 2011, 02:31:22 AM »

thanks for the nod Francois, but I can't weigh in on this one. I once had a Morse tank and loads of good intentions but that's as close as I ever got to souping reversal. I have a friend in Montreal who does this sort of stuff--I'll try asking him and report back. If it were my film, I'd try Bastian's advice on some test footage and see where that took me.

Benjamin J · « **Reply #6 on:** October 25, 2011, 04:07:40 AM »

thanks for the responses, and i'd love to hear what your guy in montreal has to say. the irony of this whole thing (for me, at least) is that E6 COLOR reversal is easy enough to do. there are kits, there are partial kits, there's film! one would think monochrome reversal would be a somewhat simpler task. when will companies realize that while film as a mass marketed factory product may be in decline, it is thriving in the small-scale DIY market?

maybe i'll just go for sabatier full reversal and a REALLY bright lamp (kidding)

Francois · « **Reply #7 on:** October 25, 2011, 02:57:11 PM »

Well, if you need some DIY formulas, just ask. I've got more than quite a few... but they all use sulfuric acid

mcduff · « **Reply #8 on:** March 23, 2015, 04:13:39 PM »

OK this is an ancient topic, but when I was googling "reversal processing" this one showed up

I have been interested in home processing super8 and I believe I have linked to this interesting and somewhat inspirational video.

Then I start digging deeper and the bleach solution is scaring the crap out to me! I have been chided a few times for being too nerdy on this site and I know need to turn to some of the folks that have teased me (who I know are fellow nerds). So I would like some help from you folks with more of a chemistry/lab background than me. All the bleach solutions suggested use 5N sulphuric acid -- I believe I am justified in being scared with working with this, correct?

I am presuming that the final solution is probably not that much worse than the bleach solutions used in colour processing, but it is the step of getting there. I guess I had some good safety conscious chem teachers, as sulfuric acid freaking scares that crap out of me

And this is not even talking about Potassium Dichromate which is pretty freaking nasty.

For the bleach solution we are talking about adding 12ml 5N Sulfuric Acid and 9.5 grams Potassium Dichromate and water to make 1 Liter

Any comments other than those listed back then?

I think I am looking for someone with some chemistry background to tell me to forget about it

Indofunk · « **Reply #9 on:** March 23, 2015, 04:43:00 PM »

I'm trying to remember back to my mol bio grad school days when we'd use all sorts of nasty chems, but I can't remember what our normal stock solution of sulphuric was. I do remember it was so damn concentrated that it would smoke as soon as you opened the bottle. The bottle, btw, was one of those glass stoppered bottles ... I don't think concentrated sulphuric can be kept in bottles with any other type of lid. But yeah, just take care, wear gloves, and for God's sake don't breathe it in! Although we had chemical hoods in the lab, I remember being quite cavalier about pouring out sulphuric in the open on the bench. Just, yeah, don't inhale

The working solution is dilute enough that you shouldn't be worried. You can even make the stock 10x less concentrated and use 120mL as long as the other ingredients don't come out to more than 1L. The .5M sulphuric stock should be a walk in the park

mcduff · « **Reply #10 on:** March 23, 2015, 05:04:09 PM »

Thanks satish - I figured you would have some experience in this. I have access to a fume hood that I could use to mix it. I guess the final solution would be almost .05m which I guess will be not too scary. The other stuff sounds nasty but then again a fume hood would deal with that. I will keep folks posted.

UPDATE: I think I am going to turn chicken and pass. It is the potassium dichromate that is the really nasty one. It is a powder and generally evil (has a 4 rating on MSDS). I guess you can use potassium permanganate which is less nasty but does not work as good.

Given the above and having to work for part of the time in the dark, I think I will live to fight another day in the darkroom

Francois · « **Reply #11 on:** March 23, 2015, 09:24:27 PM »

One of the things is that I don't think it will get in your system through the skin, which is a bonus.

When I read the MSDS for the Kodak Rapid Selenium Toner, I chickened out... this stuff is definitely scary! It said to go to hospital with the label if you simply happen to touch the solution!

I don't think things are that bad for reversal bleach baths... though you might want to check this
http://www.freestylephoto.biz/static/pdf/msds/foma/EN_Black_and_white_reversal_film_se,_part_B2.pdf

jharr · « **Reply #12 on:** March 23, 2015, 10:31:06 PM »

Does a Chemistry/Biochemistry background count?

Acid isn't scary. Just remember to keep it alphabetical (acid into water) pouring water into acid will cause unhappy reactions and breaking glass, etc. Wear gloves, goggles, etc. and do it outside with a breeze blowing across your work.

I have used quite a bit of Potassium Dichromate doing gum printing. Again, make the solution outside or in a hood and wear gloves when working with it. This is all common sense stuff and reading an MSDS should just make you aware, not scared. It's like reading a label on allergy medicine. You would think it is going to cause your head to explode and your legs to curl up like the wicked witch of the west. I worked for years with cytotoxic chemicals and never worried about being in danger from them. Take reasonable precautions to put barriers between you and the nasties and you'll be just fine.

Sulfuric acid must be stored carefully in containers made of nonreactive material (such as glass). Solutions equal to or stronger than 1.5 M are labeled "CORROSIVE", while solutions greater than 0.5 M but less than 1.5 M are labeled "IRRITANT".

mcduff · « **Reply #13 on:** March 24, 2015, 03:22:27 AM »

Thanks James. I knew you were the other person that would give good advice. Ya those msds sheets can give the willies pretty easy haha.

I think I am still gonna bail, particularly since it is a bit of a mess to do this if you don't have the super 8 reels. It means using the bucket method with a fair bit of it happening in the dark!

jharr · « **Reply #14 on:** March 24, 2015, 03:27:24 AM »

A 50ft length of hose would also maybe work (might be messier than the bucket method) if you could figure out how to thread the film without breaking it or scratching the heck out of it. Once loaded though it could be done in the light.

I think you would need around 8 liters of solutions to fill a 1 inch diameter hose.

Bryan · « **Reply #15 on:** March 24, 2015, 03:47:39 AM »

It's easy to fish the film through the hose, tie a tissue or cotton ball to a fishing line and suck it through with a vacuum. Best to lay the hose strait and tie off the end so you don't suck the whole thing into the vacuum. I've seen electricians use this method to fish wire through conduit.

The best way to develop 8mm film is with a Lomo tank, they are plentiful on the bay. I've never used one but I have heard they can be a little difficult to load the film.

Francois · « **Reply #16 on:** March 24, 2015, 01:32:43 PM »

Or... Keeping in line with the tube trick, simply making a custom tank out of black abs sewer drains with one tube that slides in another. You roll the film around the outside of the drum and insert it in the tank. The reel could be capped at both ends to reduce the amount of chemistry needed.

Hungry Mike · « **Reply #17 on:** March 24, 2015, 03:44:33 PM »

Many years ago I attended an avant garde film festival in Windsor, Ontario. One of the highlights were the Super 8mm films being presented by this German feminist / leftist / lesbian collective. One of the very sincere local Canadian filmmakers screwed up the courage to ask one of these extremely intimidating German ladies how they developed their films. She stared at him coldly & pitilessly and simply said "You develop them." The young man was so overwhelmed by the brusqueness of the response he quickly retreated.

jharr · « **Reply #18 on:** March 24, 2015, 04:38:00 PM »

Visions of monocles and riding crops... "You develop it! Schnell!!"

mcduff · « **Reply #19 on:** March 24, 2015, 09:39:47 PM »

OK I this looks like a reasonably safe bleach -- 9% hydrogen peroxide and some lemon juice!

The results are definitely low fi, but it is cool nonetheless! I know it is a bit stronger than the average H2O2 but I have used stronger concentrations for disinfecting things. Comments from the chemists?

Indofunk · « **Reply #20 on:** March 24, 2015, 10:22:48 PM »

I love the results he got!

mcduff · « **Reply #21 on:** March 25, 2015, 01:03:56 AM »

Ya I know. I think it looks pretty cool. Gritty, but that can be OK.

EDIT: still checking out if these two reasonably benign materials (hydrogen peroxide and lemon juice) are OK when together.

jharr · « **Reply #22 on:** March 25, 2015, 02:55:19 AM »

Maybe I'm just in a "mood", but I don't really like the color cast. I don't do color scans of my b/w negs. Why do it with positives? I think they would stand up well as straight b/w scans. The color reminds me too much of a lomo gimmick.

Bryan · « **Reply #23 on:** March 25, 2015, 03:57:04 AM »

Quote from: mcduff on March 24, 2015, 09:39:47 PM

OK I this looks like a reasonably safe bleach -- 9% hydrogen peroxide and some lemon juice!

The results are definitely low fi, but it is cool nonetheless! I know it is a bit stronger than the average H2O2 but I have used stronger concentrations for disinfecting things. Comments from the chemists?

Thanks for finding that, I would be interested to see how it looks on a projector.

Francois · « **Reply #24 on:** March 25, 2015, 01:02:22 PM »

Thanks McD for finding this!
I really love the results it gives. Just chunky and grungy enough for my taste.

mcduff · « **Reply #25 on:** March 25, 2015, 06:00:23 PM »

I want to try this, but I have decided I am going to wait until it is a bit warmer and I can use the bleach outside or at least in a room with proper ventilation. I also will likely work up to doing a roll of super8 as I would like to start with some more controlled experiments with a tank of 35mm film before mucking about with a bucket (or hose or whathaveyou) filled with super8 film! I have been talking with James a bit about this and for a bleach it seems that it is less nasty than some of the traditional options (potasium dichromate) but I still want to be on the safe side. Now Satish, no flowerbombing if sciency stuff gets talked about as I think it is fair to do if we are talking about our health! While this stuff does seem to be safer than the alternatives, it still is bleach, so the provisions for safety still apply. As one of my science friends did mention, acids and oxides can sometimes be pretty intense. (google "piranna solution" if you ever need a reason to be paranoid haha.)

I have corresponded with Richardo (the guy that originally posted this info) and suggested he pop around here and join in on the fun, and maybe he can talk a bit more about this process

jharr · « **Reply #26 on:** March 25, 2015, 06:17:41 PM »

Here is some info for a process that uses the traditional bleach, but replaces the flash/fix step with yet another nasty OTC chemical that you don't want to get on you.

I don't know why, but the cavalier part of me wants to just try it and see how it goes. One additional issue is where to dispose of this stuff once you use it. I can't imagine that pouring it down the drain is kosher. Maybe a household recycling center where they accept old cleansers and paint and whatnot?

https://www.flickr.com/groups/1924424@N22/discuss/72157629499928508/

Indofunk · « **Reply #27 on:** March 25, 2015, 06:41:04 PM »

Quote from: mcduff on March 25, 2015, 06:00:23 PM

Now Satish, no flowerbombing if sciency stuff gets talked about as I think it is fair to do if we are talking about our health! While this stuff does seem to be safer than the alternatives, it still is bleach, so the provisions for safety still apply. As one of my science friends did mention, acids and oxides can sometimes be pretty intense. (google "piranna solution" if you ever need a reason to be paranoid haha.)

So far, nothing is flower foul worthy. (so far) So you're safe. Keep in mind that I *am* in sunny California right now and snapping pictures of pretty flowers faster than I can buy film, so come next week when I'm back in NYC developing them, I'll have a pretty hefty backlog of flowers to post

"you've been warned"

Hungry Mike · « **Reply #28 on:** March 25, 2015, 07:31:02 PM »

Quote

but I still want to be on the safe side

With the lime juice & peroxide combo (he uses a 9% peroxide solution and I think generally drug store brands are at 3%), is the concern the potential damage to skin or disposal? In the development discussion you link to he's using lime juice which is a pretty weak acid (2 to 2.35 ph says the Internet) and because its from a fruit and not say chemically pure citric acid it is going to have a variety of buffering agents (water, plant proteins, sugars, esters, etc.) I'd guess those should buffer the chemical reaction a bit. So C6H8O6 (citric acid) + H2O2 (Peroxide) = C6H8O7 (Isocitric acid) + H2O (water)? Seems safe?

Francois · « **Reply #29 on:** March 25, 2015, 07:42:06 PM »

Just to help...
5 of the World's Most Dangerous Chemicals

then again... probably not

Indofunk · « **Reply #30 on:** March 25, 2015, 08:18:40 PM »

Surprised they didn't mention the silent killer, dihydrogen monoxide!!

http://www.dhmo.org/facts.html

Francois · « **Reply #31 on:** March 25, 2015, 09:48:56 PM »

Nah... H2O is just cake compared to these bad boys

Indofunk · « **Reply #32 on:** March 25, 2015, 11:27:25 PM »

I'll bet that dihydrogen monoxide causes more deaths per year than ALL of those chemicals in the video combined

mcduff · « **Reply #33 on:** March 26, 2015, 12:25:27 PM »

Hey just good old O2 is pretty nasty - for something that we need to live.

Back on topic (man I rarely say that), I look forward to trying this out when its warmer and I have better ventilation. I will not be starting with my noob friend and super 8 film sloshing in a bucket tho

As I mentioned I have been corresponding with Richardo (the guy doing this research whose email is avail in the link I gave) and he is now experimenting with H2O2 and acetic acid which he hopes will work even better. He said he will keep me posted. Yes, that is creating peracetic acid but his reasoning is that it is a dillute form and prudent handling etc should make it acceptable and safer than the sulfuric acid or chromate based options.

Francois · « **Reply #34 on:** March 26, 2015, 01:11:02 PM »

I wonder if hair bleach peroxide would work? It is more aggressive than hydrogen peroxide like we get at the drugstore...

As for the lime juice, I'm thinking it would be nice to standardize the pH and all by using a lime juice substitute like Realmon or something like that...

I wonder if salt and vinegar would work? I guess only a chemist would know.

Hungry Mike · « **Reply #35 on:** March 26, 2015, 02:10:51 PM »

Quote

experimenting with H2O2 and acetic acid which he hopes will work even better

I'm very out of practice with this stuff but I was thinking at first that combo would work out to water and CH3CHO (wiki says its the organic compound Acetaldehyde), but, yeah he's right, I think it should work like this H2O2 (peroxide) + CH3CO2H (acetic acid) = CH3CO3H (peracetic acid) + H2O.

Did he happen to say what strength of acetic acid he uses? If he's using regular vinegar (that's 4 to 5% acetic acid) then the resulting mixture would be weak I'd guess. So reasonable safe with precautions. If he's using something stronger... some kind of industrial strength acetic acid then I'd worry about it more. Regardless with this combo you would need decent ventilation, gloves - the works...

Quote

I wonder if salt and vinegar would work?

Doesn't table salt (so not pure sodium chloride as it has added stuff in it) act like a buffering agent? Perhaps a Caffenol aficionado can chime in as I thought I read that it is sometimes used that way.

mcduff · « **Reply #36 on:** March 26, 2015, 02:23:47 PM »

I am assuming he is just considering vinegar as his goal is to use simple, easy to access and safer compounds. So I doubt he will be subbing weak citric acid for something stronger. Plus he is not using much acid (it is a dilute version he is using and he is not using much of it), so I can't see the reason to use a strong acetic acid. But you guys with your chemistry mumbo jumbo would know more

mcduff · « **Reply #37 on:** March 26, 2015, 02:43:39 PM »

Here is the correspondence that I have had with Richardo (the fellow who has been playing with these formulations), for those that care...

Email #1

I've been doing some adjustments in the bleach, like substituting citric acid for acetic acid, it seems more stable, even if citric acid can give a more interesting tone to the film, it is not stable, and often creates blisters or stains...

I've also been testing other solutions,

As for the fixer, i'm still cheating and using normal sodium thiosulfate...

My main concern still is the developer and bleach, I was very hapy to eliminate the presence of metol, hydroquinone, potassium dichromate or potassium permanganate and sulfuric acid, so, ptassium bromide or sodium thiosulfate still exist in my tests...

Well, times of development depend on temperature, I usually use higher developing temperature, near 30ºC so I can have shorter developing times, near 20 minutes etc...

The hydrogen peroxide- acetic acid bleach is quite fast, around 1 min. but actually i've been trying to reduce it's time of action, so I can control it better, but because hydrogen peroxide is hard to stabylize, this is not an easy task,

Email #2

Well, yes, hydrogen peroxide with acetic acid creates peracetic acid,

But, using it in the dilutions I'm suggesting it's not so dangerous, of course that 9% hydrogen peroxide can dye your hair, but I don't think it can pose a big threat, unless you swallow it of course!

I'm still doing some research on this bleach, I'm preparing a new one, safer than this one though, I will have some news about it soon!

He is a nice guy so if any of you want to give him a chat, his email is in his posting http://www.filmlabs.org/docs/citric-hydrogen-peroxide-bleach.pdf

Bryan · « **Reply #38 on:** March 26, 2015, 04:22:03 PM »

Is bleach for Black and White film the same as for color? I'm wondering if this formula he's working on would work with color reversal film.

Francois · « **Reply #39 on:** March 26, 2015, 08:14:14 PM »

That's a good question but I think it probably would work fine for color film... the goal of a reversal bleach is to remove silver, just like C-41 bleach.

I also wonder i it would work using the regular 3% peroxide we have at the drugstore... maybe it would slow down the bleaching process?

I was looking at wikipedia and found this

Quote

Diluted H2O2 (between 1.9% and 12%) mixed with ammonium hydroxide is used to bleach human hair.

mcduff · « **Reply #40 on:** March 26, 2015, 08:46:18 PM »

Quote from: Francois on March 26, 2015, 08:14:14 PM

I also wonder if it would work using the regular 3% peroxide we have at the drugstore... maybe it would slow down the bleaching process?

Good question, especially since he says the bleaching is happening real fast (1 minute) so it may not hurt using a more dillute version.

Francois · « **Reply #41 on:** March 26, 2015, 09:09:06 PM »

Yeah, when I suggested the salt, I was thinking about when we were kids and we used to make pennies shiny and new by soaking them overnight in the stuff...

Hungry Mike · « **Reply #42 on:** March 27, 2015, 03:02:14 PM »

Quote

ammonium hydroxide

I believe that is what we call Household Ammonia, (NH3). I have read that a mixture of peroxide + ammonia is good for removing fungus from lenses (I've seen a variety of concentrations from 50/50 to 94 parts water 4 parts ammonia and 2 parts peroxide).

My concern for this application, using a hair bleach mixture with peroxide & ammonia rather than a straight dilution of peroxide, is how it might interact with the acid... Again small dilutions so maybe it is inconsequential. Personally I'd lean towards keeping the variables, in terms of chemicals at least, to a minimal and then expanding the experiment once some kind of baseline is established. I'd try a 3% dilution first and see what happens.

Quote

I was thinking about when we were kids and we used to make pennies shiny and new by soaking them overnight in the stuff...

Ah. Looking on APUG (which is always fraught with peril

), where they discuss this kind of thing more often than we do here, it has been mentioned that Sodium Chloride is a mild silver halide solvent and iodized table salt [because it has a tiny amount of potassium iodate or P. iodide] can be used as a restrainer in the place of potassium bromide (which is often used in home brew developer for reducing fogging I think). I was thinking that it'd just slow down the developing process with little other benefit.

Francois · « **Reply #43 on:** March 27, 2015, 08:29:35 PM »

Not like we really care about accelerating or slowing down development when at the bleach stage...