I have a question about the water to powder ratio for D-76. The instructions say to start off with 3 liters of water in which you dissolve the powder and then top off to 3.8 liters (or 1 US gallon). ...
I have an old glass positive photo from about 1850. Does anyone know what process was used? Heliotipy? Puharotipy? I'm think that the author of the image is Puhar I have an appointment with the ...