Canon F-1 (Old) and M42 lenses.

zanxion72 · Joined: 11 Dec 2012 Posts: 145 Location: Athens, Greece

After using my favorite M42 lenses on my Canon A-1 with an adapter, I am thinking of trying them on my F-1 (Old). Is metering possible with these lenses on the F-1? The lens will not be providing the camera with any aperture info, so would needle matching metering be possible?

David · Expire: 2013-01-25

The A-1 has aperture priority mode, so it should be, in theory. You'd need to use the manual diaphragm on the lens and then let the camera automatically determine the aperture. That said, when I did that with my RT (granted it's a much later camera), the results were off consistently by an amount that increased as the aperture closed. So you may need to run some tests to see if you have to compensate.

zanxion72 · Joined: 11 Dec 2012 Posts: 145 Location: Athens, Greece

I am wondering how can I have metering assistance from the camera when there is no pin to drive the aperture needle. Is there a chance of causing damage to the camera like that?

philslizzy · Joined: 07 Aug 2012 Posts: 4744 Location: Cheshire, England

Stop down metering.

zanxion72 · Joined: 11 Dec 2012 Posts: 145 Location: Athens, Greece

And here comes the really stupid question!
How can I do stopped down metering in the F-1? How do one use the needle when stopped down?

Sorry for being that ignorant!

David · Expire: 2013-01-25

With the F-1 old, metering like this will be hard. Firstly, you'll have to set the ISO to compensate for the different battery charge (unless you have your F-1 modified), but I assume you know that. Once the M42 lens is on, if it has a manual mode and can stop down, then you should be able to meter normally. On my RT I've done this and found it was accurate at the open apertures and then significantly underexposed images when stopped down. The apertures between 1.8 and 22 were on a sliding scale of meter accuracy. So there may be some compensation required for different apertures. Your best bet is to take a meter reading with, say, and FD 50mm 1.8 and record the settings for each aperture. Then do the same with, say, a Takumar 55mm 1.8 and see where they're different. That would give you a rough guide on how to compensate over the aperture range for a normal lens.

As long as the M42 lenses are away from the mirror, then I would imagine it will be okay. That said, I thought M42 had a shorter register distance than FD, so this would only be close close-up work, correct?

zanxion72 · Joined: 11 Dec 2012 Posts: 145 Location: Athens, Greece

I have been working with my M42 lenses on my F-1 (old) long now, since I had bought my adapter. They work flawlessly. I had to get used to stopped down metering, but now it has become a second nature and things are always spot on. The FD register is shorter than the M42 (42 vs 45.46mm) and any adapter works perfectly with infinity focus without any optical aids. No macro trouble here.