Measuring small quantities of liquids is a real pain for darkroom workers. The smallest graduates go down to a couple of ounces, but sometimes you need miniscule amounts, like one tenth of one milliliter! The standard photographic approach is to use the percentage-solution solution. In other words, mix or dilute more than you need in a quart of water and then draw off a dilute solution. The problem I have had with this is that I always end up wasting much more chemical than I need. And the chemicals that are needed in very samall amounts are sometimes very expensive.
But I've found the perfect answer, if you are using liquid chemicals. If you use a hypodermic needle, you can draw out exactly the amount of liquid that you need. And needles and syringes are really cheap. Let's say you need 2ml of developer Part C from the C-41 kit. With a hypodermic, that's what you'll get -- instead of mixing the whole kit.
There are a few drawbacks however. First, you may have a hard time getting the syringes and needles. In some states you need a prescription. But if you know a nurse or a doctor or have a veterinary supply store in you area you'll be all set. In fact, the vet supply stores are the best bet for the larger, horse-sixed syringes and needles. Syringes come in sizes from 0.5 ml to 60ml. Needles comes in very short, very thin sizes to very long, very thick sizes. Needs vary, but get the fattest needles that you can find. These allow the thick photographic chemicals to pass more easily. They are also harder to break by mistake.
Before you use them, make sure that you file down the tip of the needle. These buggers are designed to be sharp, and you will get stuck if you don't file down the tip. And while I've never thrown one out in 15 years of use (they are made of stainless steel), if you do have to dispose of one, do it responsibly. Wrap it well so that no one will be injured.
The idea of using syringes/hypodermic needles is a good idea, but dangerous, even if the ends have been filed down. Chemists and microbiologists often use transfer pipettes. Transfer pipettes are kind of like eye droppers, but are much cheaper, therefore disposable (I just re-use mine until I loose them :) ) Microbiologists use individually wrapped, sterile pipettes, and they run in the neighborhood of 50 cents a piece. Non-sterile pipettes are much cheaper, but the only price I know of is for sterile pipettes, as I use them for my biology experiments for school. They come in a variety of sizes, capacities and volumetric divisions should be at any science education store. The ones I use can go down to .25 mL and up to 1mL, and hold 3.5mL in the squeeze bulb. These also can be used to store pre-measured amounts chemistry in their liquid concentrate form (perfect for developing on vacation, etc...) I've managed to fit all the chemistry for four rolls of Minox film and containers to mix the chemistry in into a box for 100' of 35mm film.
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