Bronica ETRS Winding Problem

[Josh Harmon]

Hello!

I have a Bronica ETRS 75mm kit with the 120 back. I bought this last summer and have run about 30 or so rolls through it. I enjoy the camera a lot.

Recently though the battery has been dead to the point where the meter (AE II Prism) wont read but the shutter works. BUT now it takes TWICE as many winding rotations to advance to the next frame (ie four thumbflicks instead of two with the winding grip) So on my last film I only got exposures on every other shot and only got 7 instead of 15...

Also I did replace the battery with a new one and with a roll with just the backing paper (no film) it still does the same thing...

Did I switch something on? Is the back dying? I could buy another of KEH for $20...

Thanks

Josh

 

[Uncle Goose]

It could be the body as well as the back but my bet is on the back. If you know anybody with a good back you could sort this out in matters of minutes, otherwise you have to take the gamble and order a back.

 

[paul ron]

You must have done something when taking off the grip. Check it again n be sure it's on correctly, has to mate with the crank pin exactly right.

 

[Katie]

I would first suspect the grip, then the back. Rework everything and then just order a new back from KEH. If need be, you can return it.

 

[Dan Daniel]

Considering that you have exposures on every other frame, that makes me think that the back is defective, not the winder.

Take the winder off and do another test roll. You can just slide the pin back in place and twist the wind knob on the body easily; no need for a handle.

At least this will tell you if the winder is causing the problem.

All in all, the wind handle and film advance are both pretty simple mechanical devices. No tricky electronic couplings or such going on. The Speedgrip has only an electric hot shoe connection; all the other connections are mechanical. The wind lever on the grip is simply doing what you would do directly to the wind knob on the body.

 

[paul ron]

Actually taking off the grip and manually widing it is a good way to see if it the back or the grip. If the body without the grip is taking more than one turn, it is the back as suspect and not the grip. Good call.

I suspected the grip because all he did was replace the batttery on a perfectly working camera. To do that you remove the grip and doing so he may have not installed it properly in the dovetail n seated it corrctly. But you never can be certain unless you try a process of elimination.

 

[Josh Harmon]

I forgot to mention that it takes two rotations with the regular winding crank as well. I agree that it is the back that is dead.

No worries though, I see KEH has a BGN one for about $30 that should work fine... Alternately could I easily use a 220 back for 120 film? I shoot mostly B/W but I do develop my own c41 and could see myself buying some 220.

Thanks!

Josh

 

[paul ron]

You cna use 120 in a 220 back. The start point has to be different to make up teh difference of no backer paper on most of the roll. Start the leader just one tuern on the spool instead of at the arrow. That should take yuou to the first frame on teh film. Spacing will be off but you will still get all your frames.

If you have a backer paper on a spool, run it through n see want it will look like as you wind on. Mark each frame as it passes n see for yourself how the frames will look on th length of the paper.

 

[Uncle Goose]

I would strongly go against using 120 in a 220 back, the pressure plate is different in the 220 as it has no backing paper. Use the appropriate back for the 120 film, it's not gonna break your bank.

 

[BrianL]

I agree. The backs cost so little why plat with them. The inserts are the only thing different so even look for a junker and just switch the insert int your back. As for the 1 vs 2 tab back vs the i back, they are interchangeable and unless you are really a klutz the purported issue of the opening of the 1 tab back sems to only really happen if the back has not been properly closed and the safety latch clicked into place. I prefer the 2 tab back as it is actually easier to open as they deleted the safety catch that takes some dexterity to disengage. OTOH, I think when properly closed there is less of a chance of accidental opening.

 

[paul ron]

I would strongly go against using 120 in a 220 back, the pressure plate is different in the 220 as it has no backing paper. Use the appropriate back for the 120 film, it's not gonna break your bank.

The preasure plates are exactly the same in a 120 and a 220 back, with a spring loaded plate adjusted to 0.75mm-1mm clearance to the film mask.

The real difference between the two is in the frame counter n frame meter disk. The wind has to compensate the wind length of film with no paper backing. But if you start the leader at one turn on the take up spool, it will align the frames on your film strip and give you the proper amnt of pictures although the spacing may be different but not overlaped and get wider as you go to the end of the strip.

BTW... inserts are not all created equal. If you swap inserts you are asking for light leaks n latch problems. The seating is different amongst the various models.


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