Bronica PS 110mm macro f/4.5 1:1 - shutter not firing.

[Tom Kershaw]

Hello all,

I was out photographing earlier in the week with my Bronica SQ-B system and suffered a fault, in that my 110mm macro seems to have stopped firing the shutter correctly, semi locking up the camera. I exposed four rolls of film and by the last one, I had 7 exposed frames (with the 50mm wide angle) and 5 blank frames when I attempted to use the 110mm macro. I've changed the battery after the camera seemed to be "dead" but the other lens seems fine.

I have four PS lenses (2x 80mm, 110mm macro, 50mm) and two cameras so will test these all out, possibly tomorrow (Sunday), storm Dennis allowing.

Perhaps this is all my fault for not using a Hasselblad...

Tom

 

[Tom Kershaw]

I've now had a chance to double check the negatives from earlier in the week and run some test film today. It seems as though I was too quick to blame the lens; from what I can tell the problem is something related to the mirror lock up function. The 110mm & camera seem to work fine together with a cable release if not attempting to use MLU.

Failure mode as follows: lens on body, lock up mirror (mirror locks up as normal) - go to press shutter, either on camera or via release - no function.

I have a second camera body that has the MLU switch broken so cannot test this function. However the 110mm macro worked perfectly with a cable release. There are a couple more things I can try and one extra variable I introduced was to use a different film magazine for the tests but camera function / disfunction seems equivalent.

 

[Tom Kershaw]

Having read through this thread from 2015. https://www.photrio.com/forum/threads/strange-problem-with-bronica-sq-a-mirror-lockup.123133/ - I reassembled the camera, loaded a scrap roll of film and now everything seems to be working correctly. I will do a test with a "real" roll of film to check.

 

[removedacct3]

So, that basically means you do not have a reason any more to switch to a Hasselblad system, do you?

Nice to read it has sorted itself out.

 

[wiltw]

There are many interlocks in the Bronica system...

1. the pin on the back presses the interlock of the body when film is advanced (or is not needed when multiexposure lever has been actuated)
2. If the above interlock pin presses too far into the body (because of back needing adjustment), the mirror cannot flip up sufficiently to cause the shutter trigger mechanical mechanism to fully actuate
3. ...so the camera SEEMS to fire, yet the shutter never opens (and closes again) so the exposure confirmation indicator light in the viewfinder never flashes
4. ...so no exposure

Many years ago I had purchased a used back for an ETRS, and the camera had intermittent non-exposure. I sent my body + used back in to Bronica/Tamron, and they adjusted the pin in the magazine and that fixed the issue.

 

[Tom Kershaw]

There are many interlocks in the Bronica system...

1. the pin on the back presses the interlock of the body when film is advanced (or is not needed when multiexposure lever has been actuated)
2. If the above interlock pin presses too far into the body (because of back needing adjustment), the mirror cannot flip up sufficiently to cause the shutter trigger mechanical mechanism to fully actuate
3. ...so the camera SEEMS to fire, yet the shutter never opens (and closes again) so the exposure confirmation indicator light in the viewfinder never flashes
4. ...so no exposure

Many years ago I had purchased a used back for an ETRS, and the camera had intermittent non-exposure. I sent my body + used back in to Bronica/Tamron, and they adjusted the pin in the magazine and that fixed the issue.

Thanks. As mentioned earlier I'm going to try some more "real world" use and see what happens; after that I guess I would need to investigate service options in the UK for Bronica gear.

 

[Tom Kershaw]

So earlier today I reassembled the camera to the "original" spec that I was using last week, shot off a few more exposures, processed the film, and everything looks fine. The camera performed perfectly apart from slightly inconsistent frame spacing which I've experienced for a long time with the Bronica.

 

[hsandler]

I'm glad it's working again. The 110mm f4.5 is my favourite lens. This article discusses a possible failure to fire cause, but I think it applies more to the older -S lenses. If your lens tends to fire when focused at longer distances compared to macro distances, it might be due to the failure mechanism he discusses here:
http://www.buonaluce.com/sloppy.pdf

 

[Tom Kershaw]

I'm glad it's working again. The 110mm f4.5 is my favourite lens. This article discusses a possible failure to fire cause, but I think it applies more to the older -S lenses. If your lens tends to fire when focused at longer distances compared to macro distances, it might be due to the failure mechanism he discusses here:
http://www.buonaluce.com/sloppy.pdf

Thanks for the link - there is some good content on that site.

 

[Tom Kershaw]

I've just processed a couple of rolls of film post this thread and everything still seems to be working fine.

 

[wiltw]

I've just processed a couple of rolls of film post this thread and everything still seems to be working fine.

Good to hear!

 

[Tom Kershaw]

Good to hear!

I experienced a reoccurrence of a related problem recently in that mirror lock up was failing to function with one of my 80mm lenses, my other lenses (80mm, 50mm, 110mm) - all worked fine. The problematic lens did have a sticker on it so I guess I'd had trouble with this lens in the past, perhaps something has failed with the electronic communication, not sure.