Which M42 adapter (for K10D)?

ufoncz · 07-30-2010, 01:58 PM

I would like to buy some M42 lenses for my K10D and I'm not sure if every M42 adapter ring for Pentax K mount is fine. There is plenty of adapters on eBay, but I don't know the difference between one for 7 USD and another for 30 USD and I'm curious about possible issues (like focusing to infinity…). Thanks for your help and experience.

RioRico · 07-30-2010, 02:11 PM

About M42-PK adapters: Three basic sorts exist.

1) Official Pentax adapters are safe and expensive and a bit tedious. I own one.
2) Unofficial clones of (1) are cheap and variable. They MUST have the spring and clip removed OR YOU WILL GO APESHIT! I own a couple dozen.
3) Flanged non-infinity-focus adapter are cheap and safe, but limited in application. I own a half-dozen.

IMHO, the Official Pentax adapter (1) is best if you use and change only M42s all day. Leave the adapter in the camera, screw/unscrew lenses. As I said: tedious.

I put clones (2) on the threadmount glass I intend to use most, intermixed with PK-mount lenses. I use a rear lens cap as a wrench to screw the adapter tightly onto the lens. Once I learned to remove the spring and clip, I've had no problems.

The flanged adapters (3) are best used with some old cheap long teles that focus past infinity anyway; and with bellows and tubes; and for shooting where you don't care about infinity, like portraits and closeups and macros.

JeffJS · 07-30-2010, 07:13 PM

My experience dictates buying the official Pentax ones. I don't know where you are so that may be a pricey option for you. I bought a couple aftermarket adapters and they were machined so poorly that I could not get the damn thing off of the camera. It actually left metal shavings around the lens mount inside the mirror box on my K10d (that was fun cleaning out). I never tried the second one and returned both of them. Since then, Pentax only. My preference. I own 2 of them. As noted by RioRico, the aftermarkets Can work (lots of people use them), just be careful with them.

It should be noted that I own exactly 4, M42 lenses and they may see the camera 2 or 3 times per year.

Ira · 08-01-2010, 12:51 PM

99.999% m42 shooting here.

100% official Pentax adapter only.

The quality of the steel blows the clones away, as well as the machining. And here's another point--how it's threaded:

All of my Taks line up perfectly with it, whereas with a clone, your aperture ring and the entire lens in general won't screw in tight at the 12 o'clock position.

ufoncz · 08-01-2010, 11:00 PM

Thanks all for your advice, I think I will go for original part :-)

Ira · 08-02-2010, 05:11 AM

If you can get it directly from Pentax, do that, although shipping can be a little slow. Don't know what country you live in, and whether you can buy directly from their site.

Here's the link to their U.S. site:

PentaxWebstore Mount Adapter K(35m m Screwmount to Bayonet)

It's hard to find it on their site, because you have to hit "Shop," then "Web Store" to find a search field to use "adapter." The adapter itself isn't listed on any of their product or accessory pages.

07-30-2010, 01:58 PM	#1
ufoncz New Member Join Date: Oct 2009 Location: Brno Posts: 4	Which M42 adapter (for K10D)? I would like to buy some M42 lenses for my K10D and I'm not sure if every M42 adapter ring for Pentax K mount is fine. There is plenty of adapters on eBay, but I don't know the difference between one for 7 USD and another for 30 USD and I'm curious about possible issues (like focusing to infinity…). Thanks for your help and experience.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
For Sale - Sold: Industar 50-2 50mm f/3.5 Soviet M42 lens + M42 Adapter	65535	Sold Items	10	11-27-2009 04:18 PM
For Sale - Sold: M42 Tair 11-A (135mm, F2.8), Genuine Pentax M42 to K adapter	PrimeObjectif	Sold Items	15	11-02-2009 07:20 PM
For Sale - Sold: Volna-9 M42: 50mm/f2.8 1:2 macro.+ M42 adapter + auto ext.tube.	pcarfan	Sold Items	6	05-16-2009 02:53 PM
For Sale - Sold: K10D, DA 35mm Macro, 2x Macro, 360FGZ Flash, 70-210mm f4, m42 adapter and lens	drivel	Sold Items	19	08-19-2008 04:53 PM

07-30-2010, 02:11 PM	#2
RioRico Veteran Member Join Date: Jun 2008 Location: Limbo, California Posts: 11,263	About M42-PK adapters: Three basic sorts exist. 1) Official Pentax adapters are safe and expensive and a bit tedious. I own one. 2) Unofficial clones of (1) are cheap and variable. They MUST have the spring and clip removed OR YOU WILL GO APESHIT! I own a couple dozen. 3) Flanged non-infinity-focus adapter are cheap and safe, but limited in application. I own a half-dozen. IMHO, the Official Pentax adapter (1) is best if you use and change only M42s all day. Leave the adapter in the camera, screw/unscrew lenses. As I said: tedious. I put clones (2) on the threadmount glass I intend to use most, intermixed with PK-mount lenses. I use a rear lens cap as a wrench to screw the adapter tightly onto the lens. Once I learned to remove the spring and clip, I've had no problems. The flanged adapters (3) are best used with some old cheap long teles that focus past infinity anyway; and with bellows and tubes; and for shooting where you don't care about infinity, like portraits and closeups and macros.

07-30-2010, 07:13 PM	#3
JeffJS Inactive Account Join Date: Aug 2008 Location: Michigan, USA Photos: Gallery \| Albums Posts: 7,484	My experience dictates buying the official Pentax ones. I don't know where you are so that may be a pricey option for you. I bought a couple aftermarket adapters and they were machined so poorly that I could not get the damn thing off of the camera. It actually left metal shavings around the lens mount inside the mirror box on my K10d (that was fun cleaning out). I never tried the second one and returned both of them. Since then, Pentax only. My preference. I own 2 of them. As noted by RioRico, the aftermarkets Can work (lots of people use them), just be careful with them. It should be noted that I own exactly 4, M42 lenses and they may see the camera 2 or 3 times per year.

08-01-2010, 12:51 PM	#4
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	99.999% m42 shooting here. 100% official Pentax adapter only. The quality of the steel blows the clones away, as well as the machining. And here's another point--how it's threaded: All of my Taks line up perfectly with it, whereas with a clone, your aperture ring and the entire lens in general won't screw in tight at the 12 o'clock position.

08-01-2010, 11:00 PM	#5
ufoncz New Member Join Date: Oct 2009 Location: Brno Posts: 4 Original Poster	Thanks all for your advice, I think I will go for original part :-)

08-02-2010, 05:11 AM	#6
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	If you can get it directly from Pentax, do that, although shipping can be a little slow. Don't know what country you live in, and whether you can buy directly from their site. Here's the link to their U.S. site: PentaxWebstore Mount Adapter K(35m m Screwmount to Bayonet) It's hard to find it on their site, because you have to hit "Shop," then "Web Store" to find a search field to use "adapter." The adapter itself isn't listed on any of their product or accessory pages.