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blevblev
8-Jan-2008, 15:52
So I finished a Zone I test on TXP-320 / 120 film with my Mamiya 645. I want to finish doing the Zone VIII test before moving on to my field camera. According to the way Fred Picker suggests doing the Zone VIII test, he says to expose a whole roll on Zone VIII and cut it into 4 pieces for separate development. It doesn't seem like there would be enough film on a 120 roll to do that, so I'd like to use a 220 roll instead. Is 220 TXP the same as 120 TXP ? That is, will the EI that I determined for the 120 film apply to the 220 film too? I'd rather not have to go back to square one.

Of course, if there's a better way...

Mark Woods
8-Jan-2008, 16:14
Hello Blev,

I visited Building 38 in Rochester where all of the new Vision, Vision I, & Vision II cine films are made. The emulsion is coated onto the base then it goes to a slitter. The big sheets are cut down to sizes we all use. Think of the added cost there would be if a different emulsion was used for a different film size, to say nothing of the bad will of people tested in one size and the tests didn't work with the different packaged films. ;-) I used to use PXP in both 120 and 35mm and they were both the same.

Kind Regards,

Peter K
8-Jan-2008, 16:20
For 220 film you will need another rollfilm back as for 120 film. But the film itself should be the same.

Peter K

David A. Goldfarb
8-Jan-2008, 19:57
The film is the same, but if you are processing in a daylight tank with a dilute developer like PMK or Rodinal 1:100, you may get different results, because the ratio of developer to film is different, and you may have enough film area with 220 to exhaust the developer. If you're using something ordinary like D-76 or Xtol or if you process in deep tanks or if you do use a dilute developer and stack an empty reel in the tank for every reel of 220 to double the volume of developer, you should be okay.

Mark Woods
8-Jan-2008, 21:34
Excellent point!! I have 3 1/2 gallon tanks that I use to process, and don't worry.

Kind Regards,

blevblev
8-Jan-2008, 21:59
Wouldn't those effects mostly relate to the high values - developer exhaustion, that is? By the time the developer is exhausted, wouldn't the low values already be developed? If that's the case, then it wouldn't change my EI/personal ASA, and I've established that already. I can see it effecting the development time test, though.

I'm using HC-110(b), and I'll use the double size tank with an empty reel. Thanks.

Bob

blevblev
9-Jan-2008, 11:11
Actually, since I'm only developing 1/4 of the roll at a time, I don't need a bigger tank. 1/4 of a 220 reel is like 1/2 of a 120 reel and can be developed in a regular sized tank.

BTW, for the most part, I'll be using the bigger sized reel for 220 with a Nikor tank which is bigger. Does that tank hold enough developer so as to not suffer from the developer exhaustion mentioned earlier?