Another SQ question

[Horatio]

My Bronica SQ came with two backs: 120 and 220 (645 format). I’ve heard 120 film is ok to use in the ETR 220 backs. How about the SQ? I’ll probably try it anyway, just hoping to avoid wasting a roll of film.

Thanks.

 

[Rick A]

Yes, you can use the 220 back for 120. The exposure counter will not stop at 12, and continues until you get to the end of the backing paper.

 

[Horatio]

Thanks! There seem to be more 220 backs available than 120, and cheaper to boot.

 

[voceumana]

'Cause nobody makes 220 film anymore. Which is really too bad.

 

[MattKing]

Mamiya used to warn that using significant numbers of rolls of 120 film in 220 backs could cause premature wear in the 220 back (actually insert).
But to my mind, the real problem remains - it is so easy to lose track and find yourself trying to expose frames 13, 14, 15 ....

 

[Horatio]

'Cause nobody makes 220 film anymore. Which is really too bad.

Yeah. That’s a shame. Maybe one day...

 

[moto-uno]

^ Don't hold your breath . Peter

 

[M-88]

The absolutely important thing here is to know that 'film leader' of 220 film and 'backing paper' of 120 film have difference in length from a start until the point where film is attached. So when I put 120 film in 220 back of my ETRS, I have to stop winding approximately 30-35 mm PRIOR to 'start' mark. Otherwise I will lose the last frame. I'm sure the same goes to SQ as well.

EDIT: I checked the backing paper and found that I have actually marked something between 40-45 mm, not 30-35:

 

[Rowreidr]

I also use the 35mm to 120 adaptors, hand rolled 38 count 35mm film, and a precut and marked leader to get 24 frames of sprocket fun in a 220 6x6 back (SQ-Ai)

 

[Horatio]

The absolutely important thing here is to know that 'film leader' of 220 film and 'backing paper' of 120 film have difference in length from a start until the point where film is attached. So when I put 120 film in 220 back of my ETRS, I have to stop winding approximately 30-35 mm PRIOR to 'start' mark. Otherwise I will lose the last frame. I'm sure the same goes to SQ as well.

EDIT: I checked the backing paper and found that I have actually marked something between 40-45 mm, not 30-35:

Thanks for the tip!

 

[Horatio]

Thought I’d post an update. The 220J back (645 format) worked flawlessly and I got 15 exposures on the roll. I also successfully processed the roll about an hour ago. It was a test strip to check exposure consistency of each lens (80mm and 150mm). Hope to scan the negatives later today. Maybe I’ll post one or two. Now I just need a 6x6 format 220 back.

Thanks again for the responses.

 

[M-88]

Some people say 120 film in 220 back creates too much tension to winding gears which will break the back, others say film will be out of focal plane (which is ridiculous, because it's the pressure plate which is pushed further in the back, not the film pushed forward) and therefore you'll end up with unsharp images. I never had any issue with ETRS, so I'm sure your SQ will ace every frame as well. Best of luck and have fun!