Quote Originally Posted by nworth View Post
There are various grades of both distilled and deionized water. Simple, single distilled water is made in large quantities in many urban areas and is, indeed, cheap. Triple distilled water using tin condensers is used in some chemical and electronic processes and is very expensive. An elaborate deionization and filtration setup can produce water of about the same quality as triple distilled at a somewhat lower cost. A simple deionizing scheme can produce decently pure water at a cost only slightly higher than distillation and at a significantly lower hardware and setup cost. For very small scale water purification, deionization is usually the way to go.
Home stills are quite common, http://homedistiller.org/equip/photos-sold

Although the above are reflux stills in most cases, intended for alcohol, there are many others for water: http://www.jenconsusa.com/10-Water-S...ill-4000X.html and if you look at the dimensions you will see how small these are.

I am not advocating any method, just stating the fact that you can use either, and that there are advantages and disadvantages to both methods (distillation or deionization).

The bottom line is that all commercial developers and fixers are designed to work with tap water. They contain ingredients that prevent particulate matter from forming from hard water. And so, a true test is to mix some developer with tap water and look for the formation of sediment. I know that that is a harsh way to test due to expense if the test fails, but then it does work.

I don't use DW myself for mixing anything but materials for emulsion making. At EK, I did the same. We had tap water to use to test formulas with. And, what I have said goes for both color and B&W.

PE