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Is it worth buying an adapter to use M42 lenses from thrift stores?
My local thrift store has quite a few cheap ($20) M42 lenses, is it worth buying an adapter and then these lenses?
The M42 lenses don't have any scratching and look fine through viewfinders, the thrift store is selling them with film SLRs (Pentax Spotomatic).
I currently have a k-50 and the two lens kit.
Thanks

[jatrax]

Some m42 lenses are excellent and well worth getting. Some are junk just like anything.

Check the lens database before buying.

[Wild Mark]

there are very few Takumar M42 lenses that are no good. The better ones are the SMC line (better coatings).

When you buy an adapter - one rule - buy the genuine part (unless you have to suppress the 'auto' pin on the M42 lens - different type of adapter).

Cheap non-genuine adapters are hit and miss. I have had a couple now get stuck in the camera body as the 'spring' came loose and fell off. Never had that problem with genuine.

Regards

Mark

[malinku]

I highly recommend getting an official Pentax adapter if you are going to be getting the lenses. It has the best fit and is real easy to mount and unmount.

As for m42 lens their are tons of them. And a lot of them are really nice. Takumars, mamiya/sekor (with M/A switch), and of course the fancy German lenses (ziess, and the like) are all great.

I love mine but that comes from finding really good lenses.

[wtlwdwgn]

Yep, a genuine Pentax adapter is best if a bit expensive. I love my Taks and there are some great bargains out there. Here's a thread dealing with using M42s on DSLRs to help you get started. Not as easy as with later K mount lenses but still a lot of fun to shoot with. Enjoy and welcome to LBA. Bwahaha!

I don't want LBA :-(
At the moment I only have 2 lenses :-)

---------- Post added 12-18-2014 at 05:06 PM ----------

Is this the right adapter?
ebay.ca/itm/M42-Screw-mount-Lens-adapter-to-PK-for-Pentax-K-5-K-30-K-M-cameras-silver-matel-/161304652364
I haven't decided yet.
Next time I am in the thrift store I will make a list of what lenses there are, then check them out on the database.
Thanks for help.

[noblepa]

Yes, that adapter will work, although it is not a genuine Pentax adapter. Some on this board insist that only the genuine Pentax brand adapter will do. I have had good luck with third-party adapters.

I have bought an adapter for every M42 lens that I use on my dslr. I remove the spring clip on the adapter. This means that the adapter will not lock onto the camera, but, in my experience, friction has been more than enough to hold it on the camera.

There is another type of adapter, like this one: NEW M42 Lens TO PK Pentax FOR Pentax KM K M K 7 K X K2000 K20D Adapter Ring | eBay

These adapters have a large flange that sits outside the lens mount. This prevents the lens from focusing to unfinity. This is fine if you only want to use the lens for macro shots. For normal use, where infinity focus is needed, it is worthless. The proper adapter sits entirely within the lens mount. No part of the adapter extends forward of the camera lens mount.

As for those thrift store lenses. Be careful, not all M42 lenses were made by Pentax. The M42 mount is sometimes referred to as the "Universal Mount", because many camera makers used that mount. As someone else said, not many Pentax lenses (Super Takumar or Super MultiCoated Takumar) were truly bad. Just some were better than others. The same can not be said of third party lenses. Even though they will work on your Pentax dslr, many are not worth the time and effort.

[Pioneer]

All the M42 lenses I have used have been good lenses. The question is, are they better than what you are using now? You won't be able to answer THAT question until you try a few of them for yourself. Some people just like using old lenses so they don't care too much,

Having used a number of them I can tell you this much. Almost all of them will be lower contrast lenses than you are used to. This is caused as much by the coatings as anything that is or is not in the glass. Some will have more chromatic aberration and purple fringing. Finally, most will flare more than your current lenses, so it is a good idea to find some hoods.

Personally I am very fond of the Super Tak 35/3.5, the SMC Tak 50/1.4, the Super Tak 135/3.5, and the Vivitar Series One 90-180 Flatfield Zoom. But these are all old lenses so mine may just be good copies of those particular lenses. You try a few and you take your chances.

And yes...I agree wholeheartedly with the advice regarding the adaptor. Don't waste your money on the off brand ebay junk. Pony up the cash for the real deal and buy Pentax only.

[jatrax]

The question is, are they better than what you are using now? You won't be able to answer THAT question until you try a few of them for yourself. Some people just like using old lenses so they don't care too much,

Quite true. Another point is that many of those lenses do not exist in the modern catalog or if they do are extremely expensive. 55mm f/1.8? 85mm f/1.8? 105mm f/2.8? 120mm f/2.8? 150mm f/4? Now whether you need any of those is another question but they are fun to use and in M42 can be obtained at a fraction of the cost of a new one.

[marcusBMG]

http://www.nytimes.com/2008/09/11/technology/personaltech/11basics.html?pagewanted=1&_r=1&

The 50mm f/1.4 lens: Photography's Magic Bullet | Popular Photography

[Pioneer]

Thanks for the links marcusBMG.

[sbritto19]

Purchased a LOMO m42 mount for my pentax k5 ii to mount the m42 lenses. It looks good but I don't know how comparable it is to the genuine pentax m42 mounts.

[jatrax]

Purchased a LOMO m42 mount for my pentax k5 ii to mount the m42 lenses. It looks good but I don't know how comparable it is to the genuine pentax m42 mounts.

If it works it works. The issue with many of the third party adapters is poor machining resulting in the adapter and lens getting stuck on your camera. In severe cases this requires the lens to be dissembled or even destroyed to get it off the camera. That is very rare but there are many reported issues where the lens was stuck and had be man handled to get it off.

Not all third party adapters are bad and even those from the same seller seem to vary. So if yours works, you are good. If you feel it sticking or scratching the lens threads, beware.