View Full Version : old m42 adaptor

21-06-2010, 1:47pm
Hi guys,

I'm new to the forum and new to dSLR. I've just purchased a Pentax K-x with the 18-55 and 55-300 kit lens'. I'm now looking to purchase a prime and was considering either an FA or an old prime Super Tamukar 50mm F1.4 as a portrait lens. Probably go the cheap older prime to start with.

To run the old M42 screw mounts I will need an adapter. From another thread I read the following...."The old m42 lens work really well on the K-x but make sure you get the adapter that allows focus to infinity, the cheap ones with the flange on E/bay don't. "

Can someone please point me towards the correct adapter that allows focusing to infinity?

thanks in advance.

21-06-2010, 2:42pm
Mate if I were you I would grab yourself an "A" or "M" SMC 50mm in f1.7. They are an absolute bargain and the IQ is second to none. The A ones are a bit more user friendly but the M's are half the price for the same IQ. There are f1.4 versions around too but they sell for heaps more and Ive read in a few places the IQ isnt as good but that could be wrong and would be worth researching if thats what your after.
There are heaps and heaps of old lenses that work perfectly on our DSLR's. I would suggest searching on here as there have been links in the past to info regarding lenses for Pentax cameras.

21-06-2010, 6:28pm
G'Day & Welcome - lets see some images in the main forums and have fun!

Have a read of this thread... http://www.ausphotography.net.au/forum/showthread.php?t=30767 re: M42
I agree with TopGunn re; 50mm f/1.7

21-06-2010, 8:36pm
Ebay adapter on the left, Pentax on the right:



The broad flange (shoulder) on the ebay adapter is 0.75mm thick, and it pushes the lens that much further out from the correct mounting position (distance to the film or sensor). The narrow flange on the Pentax adapter sits down into the camera mount and lets the lens sit snug against the lens mount on the camera. You can also see the small spring (dark metal at 4 o'clock in the lower pic) that locks the mount into place.

21-06-2010, 9:25pm
you might find this thread useful too from within the AP site


21-06-2010, 9:28pm

sorry I am not clever enough to put two links in the one reply, but you might find this AP thread useful as well re pentax adapter; go genuine


22-06-2010, 7:44am
It looks as if someone is jumping on the adapter bandwagon. I'd shop around for a genuine one, or at least a replica. It's a good way of using your M42 lenses.

22-06-2010, 2:33pm
These mounts are available from Pentax but they wont ship to the antipodes. If you know someone in the USA you could get it shipped to them and then sent on.




22-06-2010, 2:45pm

Apparently they are still available via "Pentax Aust" for $59, which is a reasonable price to what I have seen on Ebay over the past 12 months.

"Mount adaptor K - 30120"

Hope this helps.