Posts: 1
Registered: ‎08-21-2016

help with K 3 and vivitar manual 2 x teleconverter

First I apologize for the length of this question, please bear with me.


I just got a new K 3 and I am trying out various lenses that I own.  I am trying to prepare for my first trip to Yellowstone and Grand Teton NP.


I have an old vivitar mc 2 x teleconverter which I am attempting to use with my new K 3 and various autofocus zoom lenses.  I know that I need to manually focus the lenses, that isn't the queston.  the K 3 is prompting me to enter the focal length (pg 83 of the manual) apparantly for the anti shake feature to operate properly.  The camera cannot read the lens.  The problem is that it says I need to set the focal length each time I change the zoom


obviously that cannot be done.  does anyone know what would happen if I set the focal length for the smallest focal length or the longest length or somewhere in between???  for example a pentax zoom 50 x 200 zoom


obviously the best thing to do would be to buy an autofocusing teleconverter but then there is the small matter of $$$$



I have no idea how old the tele converter is, the only markings on it are:


Vivitar MC Tele Converter 2 x PK-A/R -PK.  it has 6 contact points on the side facing the lens and the side facing the camera body has the same 6 pins plus another pin I believe this makes it:



The R-K-mount is a variation on the original K-mount by Ricoh. It supports Ricoh's own implementation of shutter priority and auto exposure modes, similar to the KA-mount but much simpler. The only addition to the original K-mount is a small pin, commonly dubbed Ricoh pin,[2] at the bottom which tells the body when the aperture ring has been set to the "P" setting (similar to the "A" setting on Pentax KA lenses). The 'P' setting is not compatible with the 'A' setting as the 'P' pin is in a different location than the 'A' contact on Pentax 'A' lenses and the flange on Pentax bodies.


The R-K-mount is used on Rikenon P lenses, Ricoh bodies that include the letter 'P' in their model number, and some non-Ricoh lenses. It is compatible with all other K-mount cameras and lenses when in manual or aperture-priority exposure modes, however the extra pin needs to be removed for safe use on autofocus Pentax cameras. The reason for this is, that the extra pin is located at the same place as the shaft used for screw-drive auto focus, where it can get locked.[2] Lenses locked to the camera body this way are difficult to remove and may require complete dismantling.


(any one know anything about removing the R pin as is suggested, is it necessary?) 


This might be the owner's manual???



so any thoughts or comments



Posts: 33
Registered: March

Re: help with K 3 and vivitar manual 2 x teleconverter

There are times when the cheap route isn't, due to the hassle involved. This is one of those instances.


Pentax makes a wonderful 1.4x teleconverter which will give you the best possible outcome. Yes, not cheap...


Set the zoom lens length to whatever you expect to use most. Another instance where complete communication between lens and camera is useful.