No 220 films available in my part of SE Asia

[hs0zfe]

These are desperate times - I do not have enough 120 film backs.

Just wondering and hoping, it might just work?!?

Cheers,
Chris

[phila]

These are desperate times - I do not have enough 120 film backs.

Just wondering and hoping, it might just work?!?

Cheers,
Chris

Dredging my memory it won't. The RB Power Back required you to select between 120/220 which changed the position of the pressure plate, compensating for the thickness difference. Maybe if you like the "out of focus" look?

[ziocan]

Dredging my memory it won't. The RB Power Back required you to select between 120/220 which changed the position of the pressure plate, compensating for the thickness difference. Maybe if you like the "out of focus" look?

maybe he does not have the same back you are talking about.

[hs0zfe]

maybe he does not have the same back you are talking about.

[font="Comic Sans MS"][/font]I meant the regular 220 roll film backs, not the motorized backs.

[mahleu]

A decent repair shop should be able to adjust the pressure plate. Alternately try it and see what happens.

[mmurph]

RB Power Back required you to select between 120/220 which changed the position of the pressure plate, compensating for the thickness difference.

The Mamiya 7II camera was the same. To go from 220 to 120 you had to rotate the pressure plate to *increase* the distance to the lens (increase the "thickness")  to allow for the paper backing on 120, that is not there on 220.

Otherwise the film is not in the same "plane of focus" as the viewfinder adjustment.

So,

1) Find a way to move the pressure plate back,

2) Re-roll the 120 without the paper backing, like 220 (not sure exactly what that would leave you with.   might have to destroy a roll to see), or

3) Test and find the focus offset on your lens, then manually adjust after focusing.

Good luck!

Best,
Michael

[Richowens]

Chris,

 From Mamiya America;

 Q. May I use 120 film in a 220 back and vice-versa?

A. Do this only in an emergency. The pressure plates of the two backs are slightly different to allow for the presence/lack of paper backing. The difference in the film plane may cause focus problems at wide apertures. Squeezing 120 film and paper through 220 rollers designed for film only will strain the back’s advance mechanism. Also, the 120 back’s counter will release after exposure #10 and waste the second half of a 220 roll. The 220 back’s counter will continue past #10, running the risk of shooting on the leader paper if strict attention is not paid to the counter.
 
 From my own experience;
 Putting 120 in a 220 back does make it harder to wind between exposures. Also the extra thickness of 120 can over time weaken the pressure plate spring. What happens then is when you use 220 in the back the vacuum produced behind the mirror, when it flips up, will pull the film out of the plane of focus, creating a very slight softness in the image. Rebuilding the backs with new springs cured the softness.
 

 HTH

 Rich

[hs0zfe]

Thank you very much - I'm very grateful! Will pay the EMS service and order in the USA.

You all better prepare your ventures when you come to shoot in SE Asia!

Chris