Originally Posted by c6h6o3
The primary reason that I vary the A to B ratio is to reduce B+F stain. Since I work with alternative processes my development times are much longer than for silver. Longer development times with any pryo developer results in greater oxidation and general stain. Increasing the amount of A relative to B reduces oxidation.
As I mentioned earlier, this probably is not of any importance if you develop for silver printing, since development times are much shorter.
Ordinarily I test for SBR with BTZS testing and adjust for subject brightness by varying the time of development rather than changing the dilution. However, there are times, say with extreme SBR conditions of -10 or more, when varyying the dilution may work better than a change in temperature.
Last edited by sanking; 12-19-2007 at 08:31 PM. Click to view previous post history.