DA 300 AND F1.7 AF ADAPTOR
Posted 29/05/2014 - 18:36 - Helpful Comment
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The DA* 300 doesn't autofocus when used with the 1.7x AF adaptor. The adaptor does all the focusing (the adaptor doesn't have the SDM contacts, so the lens essentially becomes manual focus). Because the focus range of the AF adapter is limited you have to focus the lens to approximately where you want it and then let the AF adaptor fine tune it. It sounds a bit cumbersome, but it actual works quite well, as you basically have a focus limiter. I get pretty good results with the 1.7x adaptor and the DA* 300. It's not quite so good (at least for me) with the 60-250mm.
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Posted 30/05/2014 - 11:14
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I thought that in the absence of sdm contacts the lens would work on the screw drive as it does on my K110d.
Never mind onward and upwards
Never mind onward and upwards
Posted 30/05/2014 - 11:20
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I think it's to do with the camera. The K110d could not be updated for SDM.
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Posted 30/05/2014 - 15:18
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geordie01 wrote:
I thought that in the absence of sdm contacts the lens would work on the screw drive as it does on my K110d.
Never mind onward and upwards
I think you must be mistaken. The 1.7x AF adapter can't possibly focus the lens fitted to the front of it on any camera because there is no screw drive on the female side of the adapter, only on the male side.I thought that in the absence of sdm contacts the lens would work on the screw drive as it does on my K110d.
Never mind onward and upwards
Keep in mind that it was originally designed for use with MF lenses in the first place, the adapter providing the AF.
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Posted 31/05/2014 - 05:43
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Mannesty wrote:
Keep in mind that it was originally designed for use with MF lenses in the first place, the adapter providing the AF.
it would be absurd to have a mechanical screwdrive focussing both the teleconvertor AND the lens anyway. Either one of the other but not both
geordie01 wrote:
I thought that in the absence of sdm contacts the lens would work on the screw drive as it does on my K110d.
Never mind onward and upwards
I think you must be mistaken. The 1.7x AF adapter can't possibly focus the lens fitted to the front of it on any camera because there is no screw drive on the female side of the adapter, only on the male side.I thought that in the absence of sdm contacts the lens would work on the screw drive as it does on my K110d.
Never mind onward and upwards
Keep in mind that it was originally designed for use with MF lenses in the first place, the adapter providing the AF.
[i]Bodies: 1x K-5IIs, 2x K-5, Sony TX-5, Nokia 808
Lenses: Pentax DA 10-17mm ED(IF) Fish Eye, Pentax DA 14mm f/2.8, Sigma 17-70mm f/2.8, Pentax-A 28mm f/2.8, Sigma 30mm F1.4 EX DC, Pentax-A 50mm f/1.2, Pentax-A 50mm f/1.4, Pentax-FA 50mm f/1.4, Pentax-A 50mm f/1.7, Pentax DA* 50-135mm f/2.8, Sigma 135-400mm APO DG, and more ..
Flash: AF-540FGZ, Vivitar 283
Lenses: Pentax DA 10-17mm ED(IF) Fish Eye, Pentax DA 14mm f/2.8, Sigma 17-70mm f/2.8, Pentax-A 28mm f/2.8, Sigma 30mm F1.4 EX DC, Pentax-A 50mm f/1.2, Pentax-A 50mm f/1.4, Pentax-FA 50mm f/1.4, Pentax-A 50mm f/1.7, Pentax DA* 50-135mm f/2.8, Sigma 135-400mm APO DG, and more ..
Flash: AF-540FGZ, Vivitar 283
Posted 31/05/2014 - 10:59
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Mannesty wrote:
Keep in mind that it was originally designed for use with MF lenses in the first place, the adapter providing the AF.
Nope not mistakengeordie01 wrote:
I thought that in the absence of sdm contacts the lens would work on the screw drive as it does on my K110d.
Never mind onward and upwards
I think you must be mistaken. The 1.7x AF adapter can't possibly focus the lens fitted to the front of it on any camera because there is no screw drive on the female side of the adapter, only on the male side.I thought that in the absence of sdm contacts the lens would work on the screw drive as it does on my K110d.
Never mind onward and upwards
Keep in mind that it was originally designed for use with MF lenses in the first place, the adapter providing the AF.
Lens works on 110d on screw drive, never tried it with af adaptor on that camera.
Gave it a go on K30 yesterday and it is very good
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1742 posts
15 years
Northumberland
Any thoughts
thanks
G