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Today Adorama shipped me my genuine Pentax B Adapter to mount M42 screwmount lenses onto K mount cameras. Been hunting for one awhile now. B&H says they are discontinued and they go for up to $60 on eBay. Now I can start looking in earnest for a Helios 44 - which one was it that has the swirly boheh?
Pentax Adapter B - Adapts Pentax K Bodies to Screw Mount Lenses 30120

[Xenocarcinus]

since we are on the subject, what in the world are these things and why one should not buy these ??

Camera New M42 Lens to PK Adapter Ring for Pentax K x K 7 K M K20D | eBay

I dont want to sound like a total d*ck, I am just new to this phenomenon and dont want to do anything that would ruin the camera.

Okay, I think I found my answer..... "Can not focus to infinity" with these things because they introduce a physical "gap". I would be using a 50mm lens or a wide angle fish eye (if I could get one for cheap) to take pictures of interior design spaces indoors. Do you think not being able to "focus to infinity" would be much of a handicap in such situation ?

[boriscleto]

since we are on the subject, what in the world are these things and why one should not buy these ??

Camera New M42 Lens to PK Adapter Ring for Pentax K x K 7 K M K20D | eBay

I dont want to sound like a total d*ck, I am just new to this phenomenon and dont want to do anything that would ruin the camera.

The flanged adapter is only useful for macro work. The flange sits outside the mount and adds a mm or so to the focal flange distance. This means the lens can no longer focus to infinity. It's fine to use for extension tubes or M42 bellows.

[Docrwm]

The flanged adapter is only useful for macro work. The flange sits outside the mount and adds a mm or so to the focal flange distance. This means the lens can no longer focus to infinity. It's fine to use for extension tubes or M42 bellows.

Yes, and often cheaper and less fiddly than the non-Pentax internal adapters.

[Not a Number]

Samy's Camera has them in stock for $19.95. With tax, shipping and handling it came out to $28+ change. I probably could have arranged for in-store pick-up.

http://www.samys.com/p/Camera-Lens-Adapters/30120/Mount-Adapter-K/48322.html...FWQ6QgodZT4AqQ

[boriscleto]

Samy's Camera has them in stock for $19.95. With tax, shipping and handling it came out to $28+ change. I probably could have arranged for in-store pick-up.

Pentax | Mount Adapter K | 30120

No they don't. It was in stock when I clicked your link, it wasn't when I added it to my cart...

[lytrytyr]

The SRB Griturn adapters have a good reputation:

Pentax M42 adaptor|M42 lens| Pentax K

[Not a Number]

No they don't. It was in stock when I clicked your link, it wasn't when I added it to my cart...

That was quick. Don't blink an eye!

[Steve.T]

Samy's Camera has them in stock for $19.95. With tax, shipping and handling it came out to $28+ change. I probably could have arranged for in-store pick-up.

Pentax | Mount Adapter K | 30120

Too bad, it doesn't ship to Canada!

Can someone figure out why it is called Adapter A, some however called Adapter K? are there any difference?

[boriscleto]

Can someone figure out why it is called Adapter A, some however called Adapter K? are there any difference?

And some call it Adapter B...

AFAIK Pentax has always called it Mount Adaptor K. That's how it is listed in every Pentax manual I own...though the operating manual called it Pentax Mount Adapter K...

Genuine Pentax Screwmount Lens Adapter

[Not a Number]

The B apparently means "bayonet" mount - as opposed to screwmount. Who came up with the designation is anybody's guess. It may have been listed as such in some of the accessory catalogs.

[Adam_T4]

Thank you very much for the reply !

While it is useful info it also breaks my heart as it would cost $29 + $59 so almost $80 to ship it to India.... I just cant afford that

Welcome to the Pentax Forums
Hi, OP here. The adapter finally arrived today - 7 days later (way to NOT go, USPS) - It is VERY small and was sent in a large but flat envelope. No way it can cost that much to mail to India. I'd guess more like 10 or 15 dollars U.S. Also, when I said up to $60 on eBay, that was only the HIGHEST price I saw. It's around for less than that. Or, as someone else suggested, buy several of the cheaper ones, keep the best and/or modify it for dedicated use on a particular M42 lens.
Then you can hit the streets of the huge M42 mount market. You might even try a M39 mount and using a step-up ring. Yeah Baby!
P.S. - It's made in the Philippines

[Not a Number]

The one I ordered from Samy's arrived yesterday. They packed it in a small box but it could easily have been mailed in a padded envelope at First Class rates. It was manufactured in the Philippines. Compared to the one I bought 3-4 years ago (also made in Philippines) the adapter was in a small plastic bag inside the pouch and there was an additional sheet in Japanese but lists Ricoh Imaging on it. It would appear that RIcoh is still manufacturing these and it was not New-Old-Stock left over from Hoya days.

[Adam_T4]

ou might even try a M39 mount

Correction, because of differences in the distance to the register, M39 lenses do NOT work on a Pentax DSLR when stepped up to M42. So scratch that. I did assemble a gallery of my favorite Helios samples here:
Helios Bokeh - a gallery on Flickr ((Adorama is still taking orders for them to be shipped later!))

[bass3587]

Received a shipment notice from Adorama that my adapter shipped. I'm happy but I don't have the first m42 lens to even try out . Any suggestions.

[Not a Number]

Current status when I added the item to the shopping cart is that the item is on the way to their warehouse and will be shipping in a few days.