PrakticaB -> Pentax is it possible?

lumpus · Joined: 20 Jan 2009 Posts: 51

Hi, I don't know if this is really the right place to post this question, if not a mod please move it.
My question is whether there is a way to use lenses with the Praktica Bayonet mount on Pentax DSLRs. Is there any adapter to do this? Or even a PrakticaB-M42 adapter? Thank you

voytek · Joined: 24 Nov 2009 Posts: 891

I believe there is no adapter but I know that you can convert Practicars to PK. Let me find this in a couple of days.

Jieffe · Joined: 04 Nov 2007 Posts: 754 Location: Belgium

It seems possible to engage the Praktica bayonnet for about 1 cm in the pentax mount, but without infinity ...

See here (in french) : http://forum.hardware.fr/hfr/Photonumerique/Objectifs/adaptation-objectifs-bagues-sujet_12101_10.htm

I don't have a Praktica lens thus I cannot verify that information.

koji · Expire: 2012-12-27

There is M42->PrakticaB mount adapter, but never heard of reverse
adapter yet. Since Pentax flange distance is 45.5 mm and PrakticaB's
44.4 mm, it is generally difficult to achieve infinity focus. And it seems
that Prakitcar mount is hard to file down because it contains aperture
mechanism and also no space in the lens' body base part.

If no infinity focus is concerned, you may be able to do it. But the most
of Prakticars have their M42 equivalents available such as 50/1.8 and
80/1.8 Pancolars, do you have specific Prakticars to use on Pentax?

lumpus · Joined: 20 Jan 2009 Posts: 51

infinity focus would not be a problem, I plan to use a 300mm or a 400mm lens with this mount, so I would manage without it.

koji · Expire: 2012-12-27

Okay I will bite it. Prakticar 300/4 is the latest optical design by CZJ, it is
very good lens IMO, however there is no Prakticar 400mm lens from CZJ/Pentacon.

This 300mm Prakticar has long tube between the lens body and the mount
base, which makes you a bit better for your case. Though replacing the mount
is not so easy, as I said before this base contains aperture linkage mechanism.
You can forget electrical part and make three holes in your Pentax mount base,
it would do it for you. For infinity you can shorten the above tube I mentioned.

It may not be easy, but doable. Personally I wont recommend this mod, which
may destroy not too many Prakticar 300mm F4. (I may be contradicting. Very Happy

)

lumpus · Joined: 20 Jan 2009 Posts: 51

you made your point Smile

all in all there is too much work (not that I wouldn't do it, but I don't have the skills for it) and a big chance to ruin my lens
it's times like this when I miss my old Canon who could accept almost any mount with a simple adapter
thank you very much for the responses