120 shot w/220 mask

[rpsawin]

I shoot with a M7II and shot a roll of 120 with the tension plate at 220. Other than spacing problems what else have I done?

Thanks,

Bob

 

[Steve Smith]

All you have really done is shoot with the film closer to lens by the thickness of a piece of backing paper. If you were stopped down a bit, you should be o.k.

Steve.

 

[vanspaendonck]

All you have really done is shoot with the film closer to lens by the thickness of a piece of backing paper. If you were stopped down a bit, you should be o.k.

Steve.

I don't think so.
The distance from the film guide rails to the lens hasn't changed. With the pressure plate in the 120 position, the gap between the guide rails and the pressure plate is enough to accomodate the thickness of the film plus the backing paper. In the 220 position this gap is smaller, because there is no backing paper.
Using 220 with the pressure plate in the 120 position means that the film will have a bit too much play to the rear. Most likely, the film will bulge to the rear around the middle of the frame.
I agree that you will probably be OK if you have stopped down a little.

 

[Steve Smith]

I don't think so.
The distance from the film guide rails to the lens hasn't changed. With the pressure plate in the 120 position, the gap between the guide rails and the pressure plate is enough to accomodate the thickness of the film plus the backing paper. In the 220 position this gap is smaller, because there is no backing paper.
Using 220 with the pressure plate in the 120 position means that the film will have a bit too much play to the rear. Most likely, the film will bulge to the rear around the middle of the frame.
I agree that you will probably be OK if you have stopped down a little.

Yes. That's probably what I meant to say! I got it the wrong way round.

Steve.

 

[rpsawin]

Gentlemen,

Thanks for your help.

Bob

 

[hka]

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