At our facility in the Wonderful World of Photography* we develop our film in Kodak’s XTOL, mostly. Kodak recommends a dilution of one part developer to three parts water for greatest sharpness and a slight boost in speed, to guard against underexposure.
Would you be willing to compute water temperature relative to developer concentrate temperature if the amounts were six ounces and two ounces? I don’t think so. I do it all the time, in my darkroom below the surface of the earth, by setting the metal container of working solution in a tray of hot water (cool water in summer) and stirring until the temperature reaches its goal. But we found that, if we dissolve what should make five liters in ten liters of water, it keeps just fine at that dilution for the length of time it needs to survive before being used up. (Most of us are not aware that the batch from which we work is already half-diluted.) Since it’s already 1:1, no rocket science is required to dilute once more, again 1:1, and arriving at a temperature for the water is easy to do in one’s head. Voila: 75 degrees Fahrenheit.
Kodak also recommends that a minimum of 100 ml be used for every 80 square inches of film. That’s roughly three ounces. Most of us get perfectly usable results in an eight-ounce tank, and that means that we’re relying on two ounces of XTOL, not three.
On occasion (in lieu of extreme developing times; for unique films; in efforts to compensate for major exposure errors) we recommend using the intermediate dilution directly from the available batch, in which cases we generally resort to the sliding scale for correct developing times in room temperature developer.
Here’s my suggestion, available only online: process your single roll of film in a two-reel tank, leaving the top “spacer” reel empty, thereby using at least (more, actually) 100 ml of stock solution developer. Use eight ounces of water and eight ounces of the cut XTOL, then splash out a half-ounce and use only 15-1/2 ozs. of solution in the tanks we have, in order to allow for air space so that the (gentle) agitation will work. It’s not a waste, nor is it false economy; many workers use twice that amount per roll (one roll in about a quart of working solution). When you do this, you need never say anything; simply give an exaggerated wink, and we’ll know what you’re up to.
* aka BHS
2010/11/22
Categories: Tools & Materials . . Author: mrdplus . Comments: Leave a comment