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03-10-2013, 09:17 AM   #1
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M42 to K-mount adapter

An online seller is selling a black enamel adapter to mount an M42 lens on a K-mount body. He states that it is made of duralumin,enables infinity focus and can be removed from the body by pressing with the fingernails, just like an orginal Asahi Pentax adapter. No removal tool is necessary, according to him.

As do not want to wrestle with a stuck adapter, I look forward to some advice on the advisability of buying the product.
Chhayanat

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Last edited by chhayanat; 03-10-2013 at 10:45 AM.
03-10-2013, 09:23 AM   #2
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That is a strange looking adapter. Have you considered one from SRB-Griturn? Those have an excellent reputation (never read a negative report) and are not too expensive.

http://www.srb-griturn.com/pentax-k-to-m42-3355-p.asp


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03-10-2013, 10:12 AM   #3
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Well, I guess you will have to be the first to try it and write a review
I bought a genuine Pentax one some time ago and thats the only one I use, even though it is a little wobbly with narrow-mount lenses (the Soviet Helios and Industar)
03-10-2013, 10:34 AM   #4
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"Pressing with the fingernails" indicates it has a similar spring arrangement to the OEM Pentax adapter and the various third party ones. I don't think it would be any different except for black chrome finish, there aren't really any other methods of locking the adapter to the camera.
But it's worth a try, other than that I always shamelessly pimp the SRB Griturn ones as every one I have works perfectly.

03-10-2013, 10:35 AM   #5
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QuoteOriginally posted by Na Horuk Quote
Well, I guess you will have to be the first to try it and write a review
I bought a genuine Pentax one some time ago and thats the only one I use, even though it is a little wobbly with narrow-mount lenses (the Soviet Helios and Industar)
I have the same, and it can be easily removed by just using a fingernail ... and I have noticed the wobble as well, but no big deal there ... J
03-10-2013, 10:44 AM   #6
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Thanks for the responses. Advice to use the original Asahi Pentax adapter should take into account the fact that these are not manufactured any more and prices have gone very high.

I had a look at the SRB-Griturn site before starting this thread. There seem to be no adverse reports about the SRB-Griturn but it is not clear whether this Griturn adapter needs a removal tool. If it can work in a trouble free way without having to remove the retaining spring, and if it can be removed using ones fingernails, then it would not be much different from the original Asahi Pentax adapter.
03-10-2013, 11:43 AM   #7
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QuoteOriginally posted by chhayanat Quote
Advice to use the original Asahi Pentax adapter should take into account the fact that these are not manufactured any more and prices have gone very high.
You are right, when I bought mine it cost as much as those m42 lenses I mentioned. So a third party adapter that promises the same quality might be worth a try.
03-11-2013, 10:42 AM   #8
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I know there are poorly made adapters out there, I've got one ( which I've modified and sorted ) which did get tight to remove, but it wasn't the spring because that was removed, it was the shape of one of the tapered lugs.

Of the 7 or 8 that I've got most have the spring removed and tightly screwed on to my most used M42's, most of which I have drilled or machined a slot in to accept the Pentax mount locking pin, so the lens is fixed and the spring is no longer needed. But some lenses have no place to machine a hole or slot, like the Tair 300 or the Helios 44-2, so I keep one adapter with a spring in place for these lenses and use all my 30 or so M42 lenses on any of my 5 Pentax cameras and have no trouble with lenses falling off or the adapters jamming in the lens. The Tair in particular has a tight focus and will easily turn a non sprung adapter out of the camera in 1/3 of a turn.

Using the adapter with a spring I have just spent an hour fiddling around trying to get it jammed, and I can't. But, I can see how it can get tight, and then in a panic the user might think it is jammed.
The easy way to get them off is use the tool provided with most adapters, it's easier than a fingernail for a start, and if used correctly does the job perfectly. Two ways of misusing the tool and getting the adapter tight are -
A. Putting the prongs of the tool into the slot but getting the spring on the outside of the tool, it's very easy to do and if forced ( turned to remove the adapter ) will bend the spring and probably jam the adapter badly.
B. Turning the tool and the adapter before the tool is located right in the adapter - before it has pressed the spring. This jams the end of the spring against the stop in the camera mount so it can't move into the release position. The spring is little more than a back stop / ratchet device, and this second way of jamming the spring can be done by the simple act of unscrewing the lens, if the thread is only slightly tight the spring will be hard against the stop and very difficult to press down with a fingernail, pen top, bit of stick or even the tool.

If you buy OEM or reputable adapters they will come with the tool, which used carefully is far less likely to damage the camera or the adapter than improvised alternatives.

03-11-2013, 03:46 PM   #9
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QuoteOriginally posted by Lloydy Quote
B. The spring is little more than a back stop / ratchet device, and this second way of jamming the spring can be done by the simple act of unscrewing the lens, if the thread is only slightly tight the spring will be hard against the stop and very difficult to press down with a fingernail, pen top, bit of stick or even the tool.
If you buy OEM or reputable adapters they will come with the tool, which used carefully is far less likely to damage the camera or the adapter than improvised alternatives.
If the act of unscrewing the lens can jam the spring, is it advisable then to release an adapter (in which the spring is intact) with the lens still screwed into it?
Thanks,
Chhayanat
03-11-2013, 05:23 PM   #10
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QuoteOriginally posted by chhayanat Quote
If the act of unscrewing the lens can jam the spring, is it advisable then to release an adapter (in which the spring is intact) with the lens still screwed into it?
Thanks,
Chhayanat
That works for me, I just tighten the lens clockwise slightly, press the release button and remove the lens and adapter. Then remove the adapter from the lens with a lens rear cap.
Or, unscrew the lens from the adapter, then take the pressure off the spring with a slight clockwise turn, press the spring and remove the adapter.
Both ways remove any pressure on the spring before rotating the adapter.
03-12-2013, 12:38 PM   #11
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Thanks. This thread must be one of the most useful for practical hints on how to remove an M42-Pentax K adapter.
03-14-2013, 03:33 PM   #12
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I haven't tried that one, but I love the genuine adapter. I tried a generic one that must have been mis-threaded in production...lenses all mount upside down.
03-14-2013, 03:53 PM   #13
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Hmm, interesting. Genuine ones are going for >50 or €65 at the moment on Ebay in EU. Pity its a minimum of 10 pieces.

Update
Bought a couple. Will compare against my genuine Pentax version and put a review up in a couple of weeks.

Last edited by robbiec; 03-15-2013 at 07:14 AM.
03-18-2013, 09:00 AM   #14
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QuoteOriginally posted by Lloydy Quote
Of the 7 or 8 that I've got most have the spring removed and tightly screwed on to my most used M42's, most of which I have drilled or machined a slot in to accept the Pentax mount locking pin, so the lens is fixed and the spring is no longer needed. .......
I finally got the black enamel adapter. It has no spring. It has first to be screwed on to the lens, then it takes some manoeuvring to fit the lens to the camera mount, twisting clockwise to lock, as there is no mark to line up with the orange dot.

Looks like I can get infinity focus, aperture priority in AV mode and stop-down metering with the green button in M mode. Focus confirmation is present at most aperture settings.

Pressing the lens release button and turning the lens anti-clockwise enables the lens with the converter fitted to be removed from the camera. I find the both the clockwise and anti-clockwise movement a little stiff for my liking. Equipment used: Samsung GX20; Carl Zeiss Jena Flektogon 35mm f2.4. The seller said that the converter was made in Belgium.
Many thanks to all who pitched in with advice, Lloydy in particular.
Chhayanat

Last edited by chhayanat; 03-18-2013 at 11:13 AM.
03-18-2013, 08:56 PM   #15
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QuoteOriginally posted by chhayanat Quote
Pressing the lens release button and turning the lens anti-clockwise enables the lens with the converter fitted to be removed from the camera
Does it twist off without pushing the lens release button?

Steve
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