Sandy King has announced here on APUG that he is about to undertake a controlled study of the advantages (or lack thereof) of staining developers (those containing pyrogallol or catechol). His "research questions" are as follows:

1. Are there advantages to staining developers that can be demonstrated? And if so, what are they?

2. What differnces exist among the various stining formulae, and how can these differences be exploited?

Sandy has also indicated a desire to test the claims (made by some on various fora over the years) that stained negatives scan easily, or more smoothly, than those developed in non-staining developers. Sandy, I'd be happy to help you out with this (though my film scanners are fairly low-end).

I'm sure those of us who scan our negatives would be interested in the outcome of this study. In the meantime, I'd be interested in people's experiences in this area. Are there significant scanning advantages for stained B&W negatives that can't be duplicated by the appropriate choice of a non-staining developer?

Sandy King has announced here on APUG that he is about to undertake a controlled study of the advantages (or lack thereof) of staining developers (those containing pyrogallol or catechol). His "research questions" are as follows:



Sandy has also indicated a desire to test the claims (made by some on various fora over the years) that stained negatives scan easily, or more smoothly, than those developed in non-staining developers. Sandy, I'd be happy to help you out with this (though my film scanners are fairly low-end).

I'm sure those of us who scan our negatives would be interested in the outcome of this study. In the meantime, I'd be interested in people's experiences in this area. Are there significant scanning advantages for stained B&W negatives that can't be duplicated by the appropriate choice of a non-staining developer?

I believe there are advantages to stained negatives. One of the problems in scanning is film grain, especially in mid-tones and highlights. A very large percentage of the total highlight density of a stained negative consists of stain image (dye) which has no grain. This diminishes the effect of silver grain.

This should be a fairly easy thing to compare, provided the right questions are asked in formulating the methodology of the testing.

Any comments or suggestions about the methodology would be appreciated.

Sandy

Sandy -- your premises sound reasonable. The question, I guess, is how the film scanner "sees" the highlight density (the stain density vs. the silver density).

The only comment I could make right now about methodology is that different film scanners seem to "perceive" grain in different ways. It likely has to do with the interplay between grain size and the scanner resolution. For this reason, it might be useful to compare different scanners (e.g., if you use medium-format test images, scan them on both a flatbed and a dedicated film scanner to see how the scans compare).

Jordan

The only comment I could make right now about methodology is that different film scanners seem to "perceive" grain in different ways. It likely has to do with the interplay between grain size and the scanner resolution.

Actually, I might have just as much to do with the type of light source used in the scanner as the resolution of the scanner. Grain seems to disproportionately plague the LED light source used in Nikon film scanners. Some call the effect "grain aliasing" (or "grain anti-aliasing") -- and it is a phenomenon that might be looked at with respect to staining developers.