This information I'm asking for is not on the Adox website nor is it found on any datasheet in the packaging. Does anyone know what the reciprocity figures are for Adox CHS Art 25? Or even 50 or 100 would help because I'm sure there are similar characteristics between the various emulsions. I just bought a 50 sheet box of 4x5 and it arrived today early. Now I want to shoot it, this is my first pack of Adox on 4x5. I intended on shooting tomorrow some pinhole stuff. I want to shoot this but I would like to be armed with some figures so I know how to meter my exposures for optimal effect. With the CHS series and particularly with 25 iso, I do not want to overexpose. Some films have a huge reciprocity (like Ilford, all of their films) and some have medium reciprocity (like most Kodak) and some have almost none at all (Kodak Ektachrome, Fuji Astia/Provia/Velvia). I am thinking because the CHS series is not hardened and Ilford is like superhardened by comparison (development times are very extended for Ilford as compared to Kodak) that CHS has less reciprocity than any of the other films that appear in Pinhole Designer program. Experience really counts the most. Anyone have experience on this? I want to make my trip tomorrow count because gas prices are back up again here on the Central Coast (California) and certainly don't want to overexpose.