Kodak stopped producing 620 film in 1995, but the film is still available from companies that reload 120 film onto 620 film spools. Kodak "Pan" film usually refers to Kodak Verichrome Pan, a panchromatic film with extremely fine grain and high resolving power. Verichrome pan has an ISO rating of 125. Pan film may also refer to Panatomic X, which has an ISO rating of 32. In either case, development times and processes are the same. 620 film is dimensionally identical to 120 film, so developing tanks and reels that accept 120 film will work for 620 film also.
Load the exposed 620 film onto the developing reel in complete darkness. Without turning on the light, place the loaded reel into the developing tank and put the lid on. You may now turn on the lights.
Measure out the appropriate amount of developer for your tank; most 120-sized single reel tanks take 16 ounces. The developer should be at 68 degrees Fahrenheit (20 degrees Celsius).
Pour the developer into the tank, and develop the film for 5 ½ minutes, agitating by rocking the tank every 30 seconds.
Pour out the developer and add stop bath or plain water to the tank. Agitate continuously for 30 seconds.
Pour out the stop bath and pour fixer into the tank. Agitate at 30-second intervals for eight minutes.
Pour out the fixer, take the top off the tank and wash the film in running water for 20 minutes.
Using the clothespins, hang the film to dry.