Tom,
Here's a brief description of my paper negative technique.
The biggest challenge I have in paper negative scenic photography is taming excess contrast. Paper is primarily blue and UV sensitive. MG papers have a high contrast emulsion that's blue sensitive, which will be activated by daylight. Some people have had success taming excess contrast of MG papers by using yellow filters over the lens, but I find the speed loss to be excessive, as compared to using graded paper of a moderate contrast grade (like grade 2). The nice thing about graded papers is that their contrast is not color dependant.
Firstly, you need to find your paper's working Exposure Index, through empirical testing. The Arista brand RC grade 2 paper I use rated at EI=12.
Second, you need to settle on a development method that gives a moderate contrast to the negatives while retaining adequate development (i.e. no mottling in the image, as would be the case with underdevelopement). I use paper developer diluted around 1+15, but find the contrast to be excessive unless the developer is used and/or aged. Freshly mixed developer will give noticably higher contrast to the negatives. I keep my used developer in a 1 liter container, filled almost to the top and secured with a cap to prevent excess oxidation.
Lately I've been using Ilford PQ liquid paper developer concentrate, but have had good results with Ilford Universal liquid concentrate, and also Agfa Neutol WA. The choice has more to do with availability than performance. I prefer liquid concentrates over powdered developers simply because of the keeping properties of the liquid concentrate over a pre-mixed stock solution from powder.
Even with the right developer to yield a moderate contrast negative, often the shadow details from a high contrast scene are obscured. So a slight pre-flash of exposure is often all that's necessary to raise the base exposure sufficiently to gain visible shadow detail in the negative. This moderate exposure won't over-expose the highlights, because of the logarithmic nature of the exposure values. For instance, a pre-flash exposure sufficient to render zone II shadow details is (VIII-II=2^6=64) or 1/64 of a zone VIII exposure, hardly noticeable in the highlight exposure.
I use a pre-flash light source rigged at a fixed distance above my darkroom table, and through experimentation have determined exposure times for grade 2 paper as well as Harman DPP paper. The light source is a type S-11 light bulb (standard household AC base, round white frost globe about the size of a table tennis ball, 7.5 watts), fixed inside a metal sauce can housing with a 5mm aperture hole to limit the light exposure. The light housing I suspend 30 inches above the table. I use a preflash time of 8 seconds for grade 2 paper and 3.5 seconds for Harman DPP. These times were necessary because my darkroom timer lacks the sub-1 second resolution required of a brighter light source, and warmup time of the lamp filament can become an important process parameter if the time is too short.
I had initially tried using my enlarger with lens set to f/32, but even then the pre-flash exposure times were too short (1-2 seconds) to accurately time with my old Gralab timer, hence the need to limit the light source intensity to gain longer exposure times.
I've also tried post-flashing paper negatives, after the in-camera exposure and before processing, and the results are very similar, but not exact. I suspect the pre-flashing enables the deep shadow portion of the image to overcome the emulsion's hysterisis.
After I've calibrated my process, pre-flashing is a very simple thing to do. Unload fresh paper from its box, set the timer, flash the paper, then load into the camera or film holders. Processing paper negatives is also simple, as the used developer typically ages pretty well, requiring only a development by inspection to ensure adequate development time.
Finally, I should mention, as we're getting on toward the colder months here in the northern hemisphere, that ensuring adequate developer temperature is important to yielding good results. I ensure that my developer mixture is around 68f, at which temperature I've calibrated my process to perform optimally.
~Joe
