So, I haven't dealt much with expired film, but I got a deal on a large lot of expired 220 film. I would like to test the film to determine if it's still good (I have the right to return if I want). Here's the details: Plus-X Pan in 220 Expired in around 1997 Purchased from a studio, has been frozen since it was bought new. (Even was shipped frozen in a cooler with ice packs!) I also received 5 rolls of 120 - would it be safe to use the 120 to test for the 220? I assume they are on the same base? Should I just do the normal tests for proper film speed and development time? I'm using Thornton's Two Bath developer, and Barry Thornton's method for film speed and dev time.