[lesmore49]

I have a Takumar TC bayonet mount...think it's a 2X.

If my memory serves me well, I believe I bought it new, back in the '80's. Back then Pentax used to sell new Pentax lenses and new Takumar Lenses.

Our family were very young back then so I economized with camera equipment... my wife had a K1000 and I bought a Takumar 50mm Macro, 28 mm Wide Angle and the Takumar TC.

I did splurge on a 35-105 'A' Macro Zoom (Pentax)...still have, wonderful lens.

Anyways, I never used the Takumar TC....I think it was because the only bayonet mount telephoto lens was my 35-105 Pentax and I assumed (maybe wrong) that the TC would degrade the wonderful images the 35-105 provided.

Now I have a K10D and a KM and a 55-300 (metal mount) and I'm thinking of trying the Tak 2X TC on the K10 or Km body, with the 55-300 zoom.

How to use ?

I don't have the directions anymore so I think I remove the lens, line up the red dot , fasten the TC onto the camera lens mount and then do the same with my 55-300 on the other end of the Tak TC ?

It should give the 35mm equivalent of 900mm !!!! I'm thinking my 55-300 at 300 is the 35mm equivalent of 450mm....then the TC 2 X, would be 450 X 2= 900mm.

Sounds like tripod territory, higher ISO, fast shutter speed to get a half decent picture.

Are zooms functional with TC's ?

Also, how should I set my cameras to use the old TC?

So, have I got this right ?

Picture quality:

I'm not expecting a lot, although I was more than satisfied with my Takumar 28mm and 50 Macro...I think the big diff between the Taks and the Pentax labeled lenses, was the Taks had no SMCP coating on the lens ?

But at 2 X and 900mm...seems a stretch to expect much in the way of sharp quality. I dunno.

[gp1806]

Does your 2x have the 'A' contacts? If not, you won't like it with a lens without an aperture ring. It won't allow the aperture to work. I believe the lens will be stopped down all the way. Try it and see what you get.

[Adam]

An old non-A teleconverter will make whatever lens you mount on it behave like a plain old M/K lens. Thus, follow these instruction to meter properly: https://www.pentaxforums.com/forums/pentax-lens-articles/110657-how-use-manua...7-k-x-etc.html (scroll down to the bullet points)

You won't be able to use DA or FA J lenses with manual teleconverters since they do not have aperture rings.

[lesmore49]

Thanks gp1806 and Adam for the info. I will give it a shot.

Les