How to get AF-adapter to work with 645 adapter

angus · 04-01-2011, 04:37 AM

Hi folks,

I recently acquired a really nice 645 400/5.6 EDIF lens for relatively little money, bought an adapter and was wondering, why I can't get the AF-1.7x adapter to function, i.e. focus with this set-up. Any ideas?

(I'm using a K-5)

Thx

Angus

JeffJS · 04-01-2011, 04:40 AM

The best way to use the AF adapter is to get your Lens close to proper focus. Then hit the shutter (or AF) button and the adapter should snap right into focus.

angus · 04-01-2011, 04:43 AM

Jeff, I know this from using it with my 300/2.8 A*, but here it won't start focussing at all. Possibly because there is no automatic setting? But it does work with my Sigma Mirror lens, which also just has an open aperture... ??

JeffJS · 04-01-2011, 05:26 AM

I'm afraid I don't have any more solid advice then. As a Guess, It Sounds as if the adapter may not know a lens is there. If I understand the 645 to K adapters correctly, they are just a barrel. Maybe it isn't making proper contact to the AF adapter. Similar to how we have to short the pins for some functions when using an M42 lens.

angus · 04-01-2011, 05:46 AM

This could well be the case - which pins would I shorten and how? Could somebody enlighten me or show me the way to a thread dealing with this? Thanks. It's a great lens to use by the way, comparably light and super sharp.

Angus

angus · 04-01-2011, 05:53 AM

Searched for myself and found the bit about shortening - thx for giving me the idea, Jeff, will try for that!
Angus

04-01-2011, 04:37 AM	#1
angus Forum Member Join Date: Nov 2007 Location: Germany Photos: Gallery Posts: 98	How to get AF-adapter to work with 645 adapter Hi folks, I recently acquired a really nice 645 400/5.6 EDIF lens for relatively little money, bought an adapter and was wondering, why I can't get the AF-1.7x adapter to function, i.e. focus with this set-up. Any ideas? (I'm using a K-5) Thx Angus

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04-01-2011, 04:40 AM	#2
JeffJS Inactive Account Join Date: Aug 2008 Location: Michigan, USA Photos: Gallery \| Albums Posts: 7,484	The best way to use the AF adapter is to get your Lens close to proper focus. Then hit the shutter (or AF) button and the adapter should snap right into focus.

04-01-2011, 04:43 AM	#3
angus Forum Member Join Date: Nov 2007 Location: Germany Photos: Gallery Posts: 98 Original Poster	Jeff, I know this from using it with my 300/2.8 A*, but here it won't start focussing at all. Possibly because there is no automatic setting? But it does work with my Sigma Mirror lens, which also just has an open aperture... ??

04-01-2011, 05:26 AM	#4
JeffJS Inactive Account Join Date: Aug 2008 Location: Michigan, USA Photos: Gallery \| Albums Posts: 7,484	I'm afraid I don't have any more solid advice then. As a Guess, It Sounds as if the adapter may not know a lens is there. If I understand the 645 to K adapters correctly, they are just a barrel. Maybe it isn't making proper contact to the AF adapter. Similar to how we have to short the pins for some functions when using an M42 lens.

04-01-2011, 05:46 AM	#5
angus Forum Member Join Date: Nov 2007 Location: Germany Photos: Gallery Posts: 98 Original Poster	This could well be the case - which pins would I shorten and how? Could somebody enlighten me or show me the way to a thread dealing with this? Thanks. It's a great lens to use by the way, comparably light and super sharp. Angus

04-01-2011, 05:53 AM	#6
angus Forum Member Join Date: Nov 2007 Location: Germany Photos: Gallery Posts: 98 Original Poster	Searched for myself and found the bit about shortening - thx for giving me the idea, Jeff, will try for that! Angus