Mamiya RB67 light leaks

[guna_s]

I just acquired a RB67 Pro S with 127mm 3.8C lens with 2 backs.

One is a 6x7 and the other a 645.

 

I tested two rolls of film through the camera, one on each back

and I discovered both films had light streaks at the edge of each

frame. To be precise, these streaks are appearing on the top left of

every frame.

 

While I was using the camera, I did try out portrait and landscape

shots by revolving the film back. Does one have to insert the

darkslide before revolving the film back..?

 

Appreciate all your replies..I'm new to medium format and its my first

purchase.

 

thanks..

 

guna

[scott_eaton]

Your film backs need to be re-foamed. Most decent camera shops can do this for about $50. You can do it yourself for about half that if you want to try it. This is a common problem with Mamiya and I've had to do it with my Pro S backs at lest once.

 

I'v never worried about fogging with the rotating back and I use my RB with less than mint Pro-S backs with 400 speed film in bright sunlight all the time. I don't change backs much and consequently out of laziness I haven't loaded my darkslide in ages. After I re-foamed the backs I haven't noticed any fogging at all.

 

//scott

[twmeyer]

and you can spin 'em like a top, mid-roll, without the slide and get no fogging, if the foam's okay...t

[guna_s]

Scott...where can I purchase these foams for re-foaming the backs?

[john_smith8]

I have found a really cheap solution to sealing backs. U can use the foam that u get with computer bits. U know its very similar to the mamiya stuff. Just cut it up into little strips. The problem I had was that I had big streaks across the film. replacing the mamiya foam worked. It seems like the most important part is the foam around the hinge. u need a fat piece there.

[sid_steinhaeufel]

Micro-tools sells the foam. Also, Mamiya has the individual strips of foam already cut to size but the price is considerably higher!

 

Sid