I have been really enjoying my entry into the world of pinhole photography. I am using the Ilford Titan with HP5 and Delta 100 depending on the weather; measuring the exposure with a Gossen Ultra Pro with incident readings (box speed) and converting with the Ilford exposure calculator. The film is developed in ID11 1:1 for the mfg recommended time @68F. Although I have only made 16 exposures so far and printed 4 in pt/pd all have been right on. I made a home-made "viewfinder" that has also worked very well.

My question is... I have seen a number of references to pre-flashing the direct positive paper. Why? Or would that be determined by expecting a particular lighting situation? If so, what conditions?

Thanks in advance for your input.