ISO on Kodak 6121 duplicating film. Anyone know maybe 4?

[AnselAvedon]

I recently got a box of Kodak 6121 Kodak Ektachrome duplicating film. I know it has a low ISO and I want to use that to my advantage for doing long exposure images. However I also don't want to go guessing and process 10 images before I have an answer. Is there any data sheet wheee I can read more about this film? I called their customer service only to get a lady who didn't even know what ISO was. She Acted all sorts of snobby when asking me do you even have a Catalog number and was even more upset to learn that I had the Catalog number. Cat 120 8347. She then told me this is 8x10 film and it's discontinued so we have no information. So I was told everything I already knew. Once again I just want to know the ISO I'm guessing it's at 4. But really you would expect Kodak customer service to at least know what ISO is!

[Mark Sampson]

To be sure, Kodak ain't what it used to be. My own long experience with various Kodak 'lab' films, like 6121, is that they never published an ISO number for them. This was because the were not intended for in-camera use. Rather, you would be exposing this film under a color enlarger, or in a process camera or other copy setup. Under such circumstances, you would have established a standard exposure and filtration by testing. You're way 'off the map' here, with old film and unknown lighting, so burning some film will be the only way to find a workable method. I'd cut some sheets down to 4x5 and test with those. I don't think I have any data sheets for this film any more... It's similar to 35mm 5071 dupe film as I recall though. Perhaps someone else on the forum will have tried this and give you a starting point.

[bob carnie]

I recently got a box of Kodak 6121 Kodak Ektachrome duplicating film. I know it has a low ISO and I want to use that to my advantage for doing long exposure images. However I also don't want to go guessing and process 10 images before I have an answer. Is there any data sheet wheee I can read more about this film? I called their customer service only to get a lady who didn't even know what ISO was. She Acted all sorts of snobby when asking me do you even have a Catalog number and was even more upset to learn that I had the Catalog number. Cat 120 8347. She then told me this is 8x10 film and it's discontinued so we have no information. So I was told everything I already knew. Once again I just want to know the ISO I'm guessing it's at 4. But really you would expect Kodak customer service to at least know what ISO is!

I used this film for making dupes from slides, never used it as an in camera film.

I would think the ISO is around 10- 4 but you can shoot one sheet to test push one stop as your normal , see where you are and adjust to this balance. Old Kodak resource material should be somewhere for you to read up on this topic.

[Drew Wiley]

I be surprised if it's still good. I takes some experimenting to properly balance it. No way around that. My old notes are geared to my own specific equipment, but I standardized on a 10 sec exposure under the enlarger. I also found the data sheet, and for ASA determination recommends bracketing in 1/3rd EV increments all the way from 3 to 25! - not much help, and batches varied. Yours has probably lost some speed anyway. You might try 6 as a starting point. Good luck.