Canon lens on K-Mount

bwield · 07-28-2009, 04:40 AM

I have found a Tokina ATX 90 2.5 macro lens for a great price in canon mount.
Is there any adapter that I can use to mount it on a K20D.
I am expecting that I would loose all automated control and have to use it in M, but is there such an adapter?
After doing a search all I could find was people interested in adapting K-mount lenses to canon!

newarts · 07-28-2009, 05:39 AM

Originally posted by bwield

I have found a Tokina ATX 90 2.5 macro lens for a great price in canon mount.
Is there any adapter that I can use to mount it on a K20D.
I am expecting that I would loose all automated control and have to use it in M, but is there such an adapter?
After doing a search all I could find was people interested in adapting K-mount lenses to canon!

The least costly thing to do will be to remove the len's Canon bayonet mount & replace it with a pentax bayonet mount (either scavanged from an old lens or made from a flange-type m42-K adapter.)

This will restrict the use of the lens to macros only as it won't be able to focus at infinity.

The basic problem is that the Pentax K mount puts the Canon lenses too far from the sensor, so the Canon lens must be shortened or extra optics must be added to focus at infinity.

bwield · 07-28-2009, 05:52 AM

Hmmmm... maybe thats what I will do than, since I am only interested in it for a macro sense.
Thanks!

viking79 · 07-28-2009, 07:13 AM

The only issue is if it is an EF series lens you will not have aperture control. Canon EF lenses all use electronic aperture control.

Canon is like the AB+ of blood, it is the universal acceptor, but can't donate to anyone else but another AB+ person

Nikon lenses are generally easy to convert to Pentax mount, and those with aperture rings can be used with minimal fuss.

Eric

Last edited by viking79; 07-28-2009 at 07:26 AM.

bwield · 07-28-2009, 07:17 AM

LoL I actually just emailed him about an hour ago asking if he would perform this sort of operation.

I dont mind losing infinity / aperture control as when shooting macro I usually take my time anyways.
For me small price to pay for a good deal on this lens.

07-28-2009, 04:40 AM	#1
bwield Veteran Member Join Date: Mar 2008 Posts: 444	Canon lens on K-Mount I have found a Tokina ATX 90 2.5 macro lens for a great price in canon mount. Is there any adapter that I can use to mount it on a K20D. I am expecting that I would loose all automated control and have to use it in M, but is there such an adapter? After doing a search all I could find was people interested in adapting K-mount lenses to canon!

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07-28-2009, 05:39 AM	#2
newarts Inactive Account Join Date: Dec 2008 Location: Ames, Iowa, USA Photos: Albums Posts: 2,965	Originally posted by bwield I have found a Tokina ATX 90 2.5 macro lens for a great price in canon mount. Is there any adapter that I can use to mount it on a K20D. I am expecting that I would loose all automated control and have to use it in M, but is there such an adapter? After doing a search all I could find was people interested in adapting K-mount lenses to canon! The least costly thing to do will be to remove the len's Canon bayonet mount & replace it with a pentax bayonet mount (either scavanged from an old lens or made from a flange-type m42-K adapter.) This will restrict the use of the lens to macros only as it won't be able to focus at infinity. The basic problem is that the Pentax K mount puts the Canon lenses too far from the sensor, so the Canon lens must be shortened or extra optics must be added to focus at infinity.

07-28-2009, 05:52 AM	#3
bwield Veteran Member Join Date: Mar 2008 Posts: 444 Original Poster	Hmmmm... maybe thats what I will do than, since I am only interested in it for a macro sense. Thanks!

07-28-2009, 07:13 AM	#4
viking79 New Member Join Date: Jan 2008 Location: Marion, IA Photos: Gallery Posts: 15	The only issue is if it is an EF series lens you will not have aperture control. Canon EF lenses all use electronic aperture control. Canon is like the AB+ of blood, it is the universal acceptor, but can't donate to anyone else but another AB+ person Nikon lenses are generally easy to convert to Pentax mount, and those with aperture rings can be used with minimal fuss. Eric Last edited by viking79; 07-28-2009 at 07:26 AM.

07-28-2009, 07:17 AM	#5
bwield Veteran Member Join Date: Mar 2008 Posts: 444 Original Poster	LoL I actually just emailed him about an hour ago asking if he would perform this sort of operation. I dont mind losing infinity / aperture control as when shooting macro I usually take my time anyways. For me small price to pay for a good deal on this lens.