EFKE 120 (R100) in a Koni Omega

[dr bob]

Has anyone used this film in a Koni Omega Rapid or other camera with a similar feed system? I seem to have some registration problems with overlaps which seems to indicate some sort of take-up reel diameter problem. No obvious problem in the C330f.

I've measured the film, paper, and reel diameter and can come up with no good explanation. The problem is not serious but a bit distracting. I've had no problem with PXP, TX, TXP, TMX, TMY, HP5+, or FP4. Puzzled?

 

[Jordan]

Not the R100, but I used Efke R25 in my Koni and didn't have any unusual problems (though the frame spacing with that camera is erratic /all the time/ IME). The pictures from that roll came out very well and I have a few hanging on my wall at home now!

 

[Denis P.]

I've used Efke R100, and any spacing problems are due mostly to operator error.
My Koni does have some issues with frame spacing, but not always - it starts with wide spacings and ends with some very tight... But again, not always.
I've used R100 exclusively with this camera. Happy with both the film and the camera!

Denis

 

[Jeanne]

I don't use a Koni, but I had the same problem with Efke in my Rolleiflex SL66 backs. I was ready to give up and send one of the backs in to be readjusted for the difference in film base thickness, but then I got a great tip: wind slowly and carefully. On the Rollei you wind the crank forward, then back -- I think it was not carefully completing this backward rotation that was causing my problem.

Again, different cameras, maybe a totally differend winding system, but maybe it will help you.

 

[David A. Goldfarb]

This sounds like the problem I've experienced with an old knob-wind Linhof Rollex back. The later Super-Rollex backs have a feeler wheel that meters film travel independent of the thickness of the film or the backing. The earlier backs turn a fixed number of turns, so some films work and others don't, and it's not worth fixing.

If you've got room at the end of the roll, you might just close the back and start the counter a little further past the arrow than you normally would, or you could add a couple of thicknesses of masking tape to the leader at the beginning of the roll to see if that helps. Otherwise, just experiment and see what films work. It sounds like you've already got a good selection.

 

[Konical]

Good Afternoon, Dr. Bob,

I have no experience with Efke film in my Koni, but I can agree with the comments by Jordan and Denis regarding frame spacing in Koni backs. Wouldn't it be great if someone would tool up to make new backs which would be minus the weaknesses of the original Konis?

Konical

 

[Jon King]

I recently purchased 5 rolls of Efke 100 for use in my KO. I normally use Tri-X or APX100. Hopefully I'll try it out this weekend, and I'll let you know the results.

Jon

 

[dr bob]

Thanks for the feedback so far. I use a couple of "test" rolls marked as to the spacing which I have run through. One is a TMX and the other TX. Both register properly and most importantly, identically.

To add a little more data, today I processed an Efke roll from the second back. The registration was almost identical - same spacing - same slight overlaps in the same frames. Any other ideas?

 

[Jon King]

I just opened the foil on a roll of old Tri-X and Efke R100. The film spools are the same diameter, but the diameter of the film and paper definitely are not! One or both must be thinner than the Kodak.

I haven't taken apart a Koni back, but I think that despite the straight motion of the film advance handle, the back is actually turning the film a particular number of rotations for each frame, like most cameras. The thickness difference could certainly mess this up the spacing.

Sort of makes me wonder why this isn't a problem for other cameras?

 

[David A. Goldfarb]

I think most cameras have a wheel that can measure the actual distance the film travels. It's not particularly new technology. My 1933 Voigtlaender Superb TLR doesn't have auto stop film winding, but it does have a wheel to meter the distance the film travels, and I've never had a problem with overlapping frames.

 

[dr bob]

Jking: I agree about the rather solid gearing on the KO backs. I measured the thickness of the two films with my dial caliper and found that each film is very close at 0.005 in. even though the flexibility seems to belie this. The paper however was 0.003 on the EFKE and 0.004 on the TX – rather close and almost insignificant as compared to the results. It may be just enough difference to cause my observed problems due to the difference in buildup as the leader wraps onto the take-up reel.

The EFKE film seems to work well in my C330f!?

David: the Mamiya C330f has such a device for metering but the KO does not. It seems to be set for certain film thickness and as jking mentioned, always cranks a given number of turns set by the frame number. In fact the KO is the only camera I’ve seen in which the film never contacts rollers et c. during advancement. The film moves directly from supply to take-up and only contacts the focal plane framing as the shutter release is pressed (David, I know you know all bout this, but some readers, especially those new to film and MF may not). This is the first experience I’ve had with poor operation and I will get to the bottom of it. I think I will take your advice and wind on a little extra paper on loading – maybe a couple of reel rotations. If we are correct, this will modify the registration and could correct the problem.

 

[dr bob]

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