Triscuitmeniscus

These vials don't hold a vacuum in their headspace so if you withdraw 25 ml of solution you need to let in 25 ml of air to take its place. You might as well just open up the top. Isn't one of the selling points of HC 110 that stock solutions are very stable and you don't have to resort to these sorts of drastic measures? Regardless, if you want to divide it up into smaller containers the sterile ones you linked to are overkill: regular Boston round amber bottles with standard caps will be half the price.

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. 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.

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!