E-6 processing in BTZS tubes?

[Eric Pederson]

There's a class this weekend on do-it-yourself E-6 processing (using the Kodak s ingle-use chemistry kit. I'm tempted and wondering if there is any point in tryi ng to use BTZS tubes (4x5) for this process (the center otherwise has combi-tank s which i dislike; they are oriented to roll film).

Concerns: 1) Temperature control. Would trays of water be enough to keep rolling tubes and waiting chemistry to a precise enough temperature for E-6? I don't ha ve a problem with B/W film, but that is closer to room temperature and arguably less sensitive.

2) The non-emulsion side stuck to the inside of the tube. This just requires ext ra fixing/HCA with B/W film, but I don't know if this would be feasible with chr ome film. Could the post color developer be done outside of the tubes (warmed 5x 7" trays of chemistry)? From the directions, the temperature control and perhaps the agitation is less critical after the color development.

3) Film is not continuously in the chemistry so perhaps there would be problems with consistency -- again, no serious problems with B/W film. This might particu larly be a problem during the 15-20 seconds it takes to remove a cap, drain, and screw on a new cap with new chemistry inside.

Thanks in advance!

[Gudmundur Ingolfsson]

There is a link on this page about sheet film home brew E-6. But I would not try it for any consistent result with anything less expensive than a manual JOBO lab. Something like CPP. The first developer is very sensitve to temprature and a 0,5 degrees centigrade off screws your film speed. But if you shoot a lot of 4x5" cromes this is a way to save money.