Reciprocity failure and Arista APHS Lithographic film

Hi,
This weekend I have a chance to take some picture and it will be my only chance because it is far from my house and I want to use Arista APHS Lithographic film with my pinhole camera. I am going to use ISO 6, I will be outdoor and it is suppose to be sunny. I was wondering if someone could give me some advice with the reciprocity failure of that film. I imagine that before apply the reciprocity failure time I will have a 2 minutes exposure. Do you think I should double the exposure or give more? Thank you Jacques

Go out and take some trial pictures today and see what turns out.

Lithographic films tend to exhibit very little reciprocity failure. Also very little latitude. You either hit the exposure or you don't. I'd follow Nicholas' advice and give it a quick test before you take it on a trip. In any pinhole exposure, it usually doesn't hurt to give a little extra light to the film. With a 2 minute exposure, giving an extra 20-30 seconds will never hurt. It's less than about 1/3 stop!

Peter Gomena