Potentially stupid pt/pd question
I started calibrating my new shipment of Coventry Rag Vellum paper, which Legion assured me was te same as their Coventry Rag (thanks to Eric for the recommendation and sample). Right out of the box, I could tell you that it's not the same. But I swiped it with a pH pen, and at least looked acidic enough for pt/pd, so I decided to give it a try. I'll start with my workflow. I pre-humidified the paper at 55% RH for a half hour, coated, then let it dry in 55% RH for another half hour. I exposed a 31-step tablet for 6 minutes, developed in potassium oxalate (100 degrees F), cleared in hypoclear+EDTA. This has been my normal workflow and until now proven to work well. Now here's what I'm encountering. First of all, the Dmax is nowhere near what I would have expected. I don't have access to a working densitometer, but I'm guessing it's about 0.9. The other issue is that it took twice as long to clear as any other paper I've used. So here's my question. What are the possible causes for this? Are these issues independent of each other, or could they have the same cause? Thanks, Camden Hardy camden[at]hardyphotography[dot]net http://www.hardyphotography.net
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