m42 adapters: results summary

I have had two non-chipped M42 adapters from random HK eBay sellers - both have worked perfectly and focused to infinity with various lenses on my A100, A300 and A350.

joerun wrote: hello, I bought one I too. As I turn on the camera (A100)I sound (noise) like trying to AF for 10" is normal? Let me know THANKS

Have you set the camera on manual focus? If not, the AF will cycle and try to focus the lens at infinity.

I discovered that the noise is normal ........
happy Easter. thanks to all


How to use:

a.      Mount the adapter (with the lens);

b.      Turn on the camera (motor will starts and make a few seconds noise, to self-examine) aperture value now will show as f1.7 (pre-set value);

I have four M42 adapters, two chipped and two not. Only the black Kawa unchipped one slightly misses infinity... which is a pitty because it seems well made. The black Travor unchipped one looks quite thin -- sanded down? -- and seems to allow focus slightly past inifinity, which is annoying, as is the fact that no M42 lens seems to stop in the right rotational position. Both chipped adapters are chrome plated brass and have no trouble with infinity; one claims to be 100mm the other 50mm, both f/1.7. In any case, both chipped adapters are very touchy, often causing the camera to re-neogiate with the lens when I turn the focus ring. It seems to be a wear or dirt problem. The chips do not have gold contacts, and I've noticed that they do work better after cleaning with a pencil eraser.

Any suggestions? The reset problem is really getting quite annoying.

BTW, I'm using these primarily on an A350. They don't fit my A100 as well.

zekewhipper wrote: I have read through this entire thread, and so far no one can recommend a non-chipped but just a plain ordinary M42 adapter that will fit and provide infinity focus on a 7D. Does that mean that there is no such thing?

There is such a thing, I bought a no-name, cheap black one from Hong Kong about a year ago for about $7, and it focused to infinity. Using Vernier Calipers, the flat round bit that goes against the camera measured 0.9mm thick.

My other unchipped one, and two chipped ones, I attacked with sand paper on the front where the lens goes, and one of them I used a file on a flange on the back part where the camera goes, to get them down to 0.9mm thick.

The most recent black chipped one that I got from Hong Kong, was nearly the right thickness, and didn't require that much sand papering to get it right.

Why so many adapters, you may ask? My older Haoda chipped adapter doesn't work on my A550, but the black Hong Kong one does. And I can't be bothered taking an unchipped one off and on my Peleng Lens all the time, so it's there permanently, with a Minolta back-end lens cover on it.
Regards,
Renato

Do the focus-confirm adapters work with all m42 lenses?

I don't see anything on the back of my 28mm Vivitar lens that would communicate with the adapter chip. How does this work?

I don't want to spend the money and then find out the focus confirmation doesn't work.
Thanks,

The main purpose of the chip is to make the camera "see" the lens.

In very basic terms when the camera is switched on the processor initially checks each camera function and also sends a signal to the contacts on the lens, the chip responds saying in effect yes there is a lens fitted and my maximum aperture is xx (xx = an F value programmed into the chip, usually during manufacture)

If the camera sees this then the focus confirm will function, if the adapter has no chip, it can not respond to the camera, hence the focus confirm function is not made available.