Re: Pyro processing/Densities of a Stouffer step wedge

DEREK WATKINS (100015.635@compuserve.com)
Fri, 16 Jan 1998 09:50:14 -0500

Cor

>Could Pyro help me out on the following?: Some time ago I bought quite
some "obscure" 4*5 inch film: Efke PL100M made in Zagreb, Croatia,
formally made in Germany, known as ADOX. I am not able to get a higher
Dmax (corr.) of about 1.7. I used D76, D19 and Xtol finally undiluted and
for max. of 14 min (incedentally: with the 35 mm version of supposely the
same emulsion I obtained Dmax of around 3!). So could Pyro boost my Dmax
for Alt. Processes? <

I don't see why not. The stain would only increase the effective Dmax to
blue light and UV, but that, of course, is what you're looking for.

>An (slightly) related question: Can one "translate" the numbers/steps of a
Stouffer Step Wedge to the Zones of The Zone System i.e: Step number 5
eqquels Zone V ? I tend to think so: I took densitometer reading of all
steps, and step 5 reads (corr. for B/F) 0.66. One of my books gives a
corr. D for a greycard/Zone V as 0.70, so that seems to fit. <

It would depend on what gamma you develop your own films to. For example,
Zone VII may relate to step 9 of your Stouffer Step Wedge with one
development time and to step 11 or step 7 with a longer or shorter
development time. But in theory, it should work.

Hope this helps.

Regards
Derek