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GeneralWhat chemicals do I need, at minimum?At minimum, you will only "need" developer & fixer. That's it. Now, that doesn't mean that you can't use more. In fact, there are several other chemicals that are commonly used. They are listed in the next question. What additional chemicals do you recommend?In addition to just developer and fixer, you'll probably also want to get at least hypo-clearing agent. Also known as a wash aid, this solution helps you wash out any residual fixer (colloquially known as "hypo," thus "hypo-clearing agent") out of the film. Common brands include Kodak HCA, Heico Permawash, and Ilford Wash Aid. Significantly, HCA also helps clear out the anti-halation dye from film, which causes some processed negatives to come out with a purple tint. Usually, HCA is used after the fixer (with a short rinse in between). I've seen it used anywhere from 1 minute (30s agitation, 30s standing) to 3 minutes (constant agitation). I usually pour it in, agitate for 30s or so, then let it sit for "a while." Not an exact science, but it seems to work. Another chemical that is commonly used and that I recommend is a wetting agent. The most common example is Kodak Photo-flo. It's a detergent-like solution that helps water drip off the film during drying. This helps to eliminate water spots. Even though many people get away without it, I figure it's cheap and it doesn't hurt. One recommendation - use no more than half of the recommended dilution. I put 3 drops into a liter of water, and let the reel soak in it for 60s. What is the common sequence for using these chemicals?
Does it matter which brand I get vis-a-vis the brand of film I use?Bottom line: NO. Chemicals all work on the same basic concepts. Developers do their thing (convert the exposed silver to something else, something like that), stop baths neutralize the developer, fixers remove the undeveloper silver, etc. Technically speaking, you can use any developer/stop/fixer combination from any brands with any film. Of course, that doesn't mean there aren't some combinations that are better than others. See my Developer's and Times page for my input on various combinations. DevelopersPowder vs. liquid concentrateDevelopers come in either powder or liquid concentrate form. You mix up the powder into a stock solution which you can then either use undiluted or diluted. Liquid concentrate developers are already stock solutions and must be diluted prior to use (you can't use them undiluted). Other than the fact that some developers only come in one form or the other (e.g. - Rodinal only comes in liquid, ID-11/D76 only comes in powder), the only compelling reason to pick one or the other is convenience and preference. Powder developers are less convenient since you have to mix them up (and also introduces the possibility of inhaling the chemicals), but are far cheaper to ship. Liquid developers are super-convenient, but you have to pay to ship all that liquid. Personally, I use whatever form my preferred developers come in. The never-ending battle between fine-grain and high sharpnessDevelopers fall into 2 broad groups - fine grain (solvent) developers and high sharpness/definition (acutance) developers. Basically, fine grain developer use some chemical (usual sulfite) to dissolve grain, whereas acutance developers increase sharpness through increasing the micro-contrast between light and dark areas. The problem is that you can't have both fine grain and high sharpness. As you dissolve grain, you also dissolve the little details that separate one grain from another. As you increase sharpness, the grain really begins to pop out. Therefore, you have to pick your poison for your application. There are some times when you want high sharpness (landscapes usually need as much detail as they can get), whereas some other situations might call for as smooth a grain pattern as possible (portraits). Also bear in mind that, as you dilute fine grain developers, you are also decreasing the amount of sulfite and therefore increasing sharpness. D76 1+1, for instance, will be sharper and have higher grain than D76 straight up. In fact, D76 1+3 is considered to be an acutance developer. How much developer do I need in the tank?This one question seems to cover two separate topics. The first one is how much actual developer is needed to cover one entire roll of film. For instance - Agfa recommends that 10ml of Rodinal concentrate must be in the tank for each roll of 35mm film*. If there is less than that, you'll exhaust the developer before you are done actually developing. All developers have this minimum amount. Over time, I'll try to list them here. * - the amount of developer required is actually based on the area of film being processed. Therefore, the following sizes and quantites are all equivalent:
The second question usually means how much total solution needs to be in the tank. This is the actual liquid you pour into the tank, not the percentage of that which is undiluted developer. Technically, you only need enough to cover the reels. If you're using the common 2-reel Paterson style tank for 35mm and have only 1 roll of film in there, you could get by with only 12 oz of liquid. This will be enough to fully immerse the lower reel. However, I recommend that you put the full 20-24 oz that the tank requires. If you have only 12 oz in there, the developer could potentially move around so violently as you agitate that you'll get surge marks eminating from the sprocket holes. *One thing you should always do is to have 2 reels in a 2 reel tank, even if you are only developing 1 roll of film. This will prevent that lower reel from moving out of the solution if you do use only the minimum volume. Stop BathWater vs. "actual" stop bathsThere is a debate about whether development should be stopped using an actual stop bath or with a series of water washes. A "real" stop (which is usually acidic) halts development pretty much instantaneously. This allows you to highly control development and makes for a quick 30 second step. The common argument against using a stop bath is that it can be so sudden that it can leave pinholes in the film. However, that is really only an issue with thinner emulsions, such as Efke films. Modern films are more than durable enough to avoid pinholes. The benefits of a water stop are that it is more gentle on the film and allows for a tiny little bit of compensating effect. Personally, I use a water stop bath, and do 3 rinses. The first two are pour & fill, the last one involves 15 seconds of agitation. FixersAlkaline vs. acid fixersMost fixers are acidic by nature. While this isn't a problem unto itself, it makes washing out the fixer a bit harder. It is recommended that one use a hypo-clearing agent to help wash out the fixer. However, if one uses an alkaline fixer, you don't have to use an HCA to get the fixer out. Of course, since I recommend using an HCA wash anyway, I have no problem using an acid fixer. I use Ilford Rapid Fixer because it's been easy to get so far. Actually, right now I'm messing with Clayton's Odorless Fixer - my point is that I use whatever I can get my hands on. The most common example of an alkaline fixer is Photo Formulary's TF-4. Their TF-3 comes up a lot, too, but you have to mix that up yourself. HCA & Wetting AgentsHypo-clearing agentsHypo-clearing agents, as mentioned above, are used as aids in washing out the fixer (hypo) from the film. I honestly have no idea how it actually works (but I think it has to do with sodium), but it does. With the use of an HCA wash, the final wash step is much faster. For instance, you can use the Ilford washing method, which is much shorter and more economical with water than the old-school "5 minutes or more under running water" technique if you use an HCA wash (or, actually, if you use an alkaline fixer, as described above, but since Ilford doesn't make an alkaline fixer...). Another signficant benefit of using an HCA wash is that it will help pull out the last of the anti-halation layer that yields that purple tint to the negatives. Wetting agentsA wetting agent is a detergent-like liquid that helps water "slough" off the film faster while drying. This helps avoid water marks on processed film. You usually put the film into the wetting agent solution for a minute or so, shake off the excess liquid, then hang to dry. Some folks (including me) put the whole reel in there, others take the film off the reel and work it in and out of a little tub, coating the entire strip. Whatever you do, dilute it more than recommended - don't put more than half as much wetting agent into the volume of water as is indicated on the bottle. For Kodak Photo-Flo, I use 3 drops in a liter of water. ResourcesBooksWebsites
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