Koni Omega Rapid 100 rangefinder adjustment

[altair]

Hi all. I recently acquired a Koni Omega Rapid 100 camera together with the 90/3.5 Super Omegon lens. Everything seems to be fine except for the rangefinder. The RF patch is contrasty & clear but it appears to be off, i.e when I focus on something via the RF patch, then check the distance scale, it tells me that the target is 8 feet away when in actuality it's more like 10 feet away!

What can I do to rectify this problem? Is there an easy step-by-step walkthrough of what one needs to do to check & then realign the rangefinder? I haven't been able to find a downloadable repair manual. I'm not good with my hands though, all thumbs...but would try anything reasonably easy.

Could it just be that my focusing knob is misaligned somehow?

I haven't run a roll through the camera yet to check the focusing thoroughly and I haven't a ground glass or tracing paper handy.

I'm in Malaysia, so sending the camera to Greg Weber is hardly an option.

Would appreciate all feedback, thank you in advance.

-Dani

 

[Barry S]

Instructions here.

 

[MattKing]

I would check first to see whether the RF is actually correct - the focusing scale on the focusing knob is only relevant for scale focusing and the use of manual flashes.

In addition, I would check that the focusing scale on the knob is the right one.

 

[ausphoto]

I would underline Matt's suggestion. Check that whether the RF is actually correct. Set up a test battery with camera on tripod and targets (chairs, people) at set intervals and focus on one ect..

 

[Konical]

Good Morning, Dani,

Temporarily tape a piece of waxed paper over the film plane; check to see if sharp focus there coincides with what the rangefinder gives you.

Konical

 

[MattKing]

I would underline Matt's suggestion. Check that whether the RF is actually correct. Set up a test battery with camera on tripod and targets (chairs, people) at set intervals and focus on one ect..

A picket fence makes a great focus target . Just shoot along the face of it so that different pickets are at different distances from the camera.

Remember to bring a tape measure, some tape and some scraps of paper that you can mark with the different distances.

And of course a tripod.

 

[altair]

Thanks for all the replies, everyone.

Barry, you're a lifesaver, thank you! I'll go through that instruction, and I'll do as it says pretty soon..I just need to get the right tools for the job first.

MattKing: I've recently run a roll through the camera, all shot wide open and while I didn't shoot any picket fences (there aren't any here!), I can see from the photos that I got that the rangefinder is indeed off..the camera is front focusing by about 2-4 feet or so. Prior to that I had tracing paper stretched across the mirror box while the camera was on a tripod, but this method was iffy at best so in the end I decided to shoot a roll through it anyway. As for the focusing knob being the correct one, I can't tell.

Konical: And a good day to you, Konical See my reply to MattKing above. Did the waxed/tracing paper method but found it to be iffy, I couldn't be sure if the paper was stretched tightly at the exact same plane as the film plane. Thanks for the suggestion, however...

 

[MattKing]

The distance scales on the disc on the end of the focusing knob varies slightly - there are some cameras out there that have scales that don't match the lenses used. Just make sure that the disc on yours includes the distance scale marked with your lens' focal length, and that you are reading from that scale.