A second back for my Mamiya RB67

[removed-user-1]

Finally, after 20 years of involvement in photography, I actually possess not one but TWO film backs for my RB67. This is the first time in my life I'll be able to use one roll film camera with more than one film without unloading or carrying a second body! Now I can carry Astia and Plus-X at the same time.

(Aside - I did once shoot LF and I had multiple 4x5 film holders for my Calumet monorail camera, but that's a different realm altogether)

Also, I only paid $32 (!) for the second back, at my local shop, Biggs Camera, in Charlotte, NC. Even KEH wants $70+ for an RB back.

 

[David Brown]

You'll wonder how you ever did it before.

When I'm shooting churches, for instance, I carry PanF in one back for outdoors, and TriX or HP5 in the 2nd back for the interiors. Yes, I could have shot both with one film, but I didn't have to. Color/B&W makes even more sense (if you're into that sort of thing, e.i. color )

Just be patient looking around, and you can usually pick up backs for $25-30.

 

[xtolsniffer]

I have 4, Velvia 50 in one, Provia in the second, FP4plus in a third and Reala in the fourth. That pretty much covers every eventuality...

 

[EdColorado]

I think I have 7 now. Its a sickness, sort of an obsessive compulsive disorder. I look at the KEH web site and next thing I know I own another damn back. I still need a 6x8 though...

 

[Sjixxxy]

I've been buying backs like crazy for my RB67. I'll say this, after reloading more then once on a day which was about 0F, every extra back is a godsend.

 

[Alexander Ghaffari]

I have two 120 backs for my RB and one 220 back, but I want more 120 Pro-SD backs.

 

[stradibarrius]

Can you use 120 in a 220 back? I have a 220 back that I don't use very often but would love to be able to use 120 in it!!!

 

[xtolsniffer]

The 'conventional' wisdom is 'yes and no'. 120 film has a paper backing all the way along, 220 only on the start and end of the film. So to get the same lens-to-film distance, the 220 back has a pressure plate that is a little further forward than a 120 back to take account of the film thickness. The power backs that can take 220 and 120 film have a moveable pressure plate that takes this into account. So technically if you put 120 film into a 220 back, the surface of the film would be closer to the lens due to the backing paper and you might then get a focussing error. I have never tried this myself, so I have no idea what the actual effect would be, though I imagine it would be small. You also have to remember to stop shooting once you reach 10....

 

[Steve Smith]

I've been buying backs like crazy for my RB67. I'll say this, after reloading more then once on a day which was about 0F, every extra back is a godsend.

I must be odd then. I have two backs but I only take one out with me and I leave the darkslide at home.

I'm perfectly happy changing the film with the back in place on the body and after shooting half a roll with the darkslide just 1/4" out, I prefer not to use it.


Steve.

 

[MattKing]

The 'conventional' wisdom is 'yes and no'. 120 film has a paper backing all the way along, 220 only on the start and end of the film. So to get the same lens-to-film distance, the 220 back has a pressure plate that is a little further forward than a 120 back to take account of the film thickness. The power backs that can take 220 and 120 film have a moveable pressure plate that takes this into account. So technically if you put 120 film into a 220 back, the surface of the film would be closer to the lens due to the backing paper and you might then get a focussing error. I have never tried this myself, so I have no idea what the actual effect would be, though I imagine it would be small. You also have to remember to stop shooting once you reach 10....

The position of the film isn't determined by the pressure plate - it is determined by the film gate. The pressure plate ensures flatness.

For that reason, a 220 back may put more pressure on the film + backing paper sandwich in a roll of 120 than what it's designed for.

I would try it with something mainstream (not Efke or any other "softer" emulsions) and check very carefully for scratches.

You may see spacing differences as well, and the counter function would obviously be inaccurate.

Here is what the FAQ section on Mamiya America's website says:

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.

Matt

 

[Screwdriver]

I am thinking about getting a second back, but in reality, 10 shots on the RB67 happens so quickly, that going to a different film is easy.

But I do like KEH and want to support the US economy.