Every once in a while, I get a question or two from people getting into film photography about how to mix chemicals for their development. Sometimes they want to know the in’s and out’s of the basics, other times they’re looking for tips and tricks. One issue that I’ve seen come up time and again is the matter of calculating just how much water to mix with a stock solution. What does 1:13 mean exactly? How do you figure that out?

While the math is not terribly hard, the problem I have is trying to explain the math in such a way that it becomes easy to understand. I decided then to employ the math via jQuery and jQuery UI in a little project I like to call photography chemistry volume based on parts calculator. You put in the parts and your volume, it breaks it down for you. The further math explanation is below the form.

Why no volume units (ala milliliters or ounces)? No need as long as you know that the volume you put in is what your parts will be based in.

Yes, it’s simple. But I guess that’s the point. :-)

The link, for those who didn’t see it in the paragraph above: photography chemistry volume based on parts calculator