Sirius SR-G 28 -108mm
Posted 18/05/2011 - 22:00
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blackwill wrote:
Really stupid question I bought a Sirius SA-G 28-105 mm lens, it does not fit my K7. The person I bought it from says there is a converter that will allow me to use it. Is there such a thing and where can I get one?
Not so stupid really - you need the answer. Don't ask - don't find out.Really stupid question I bought a Sirius SA-G 28-105 mm lens, it does not fit my K7. The person I bought it from says there is a converter that will allow me to use it. Is there such a thing and where can I get one?
Is the Sirius a screw-mount or a bayonet fitting?
If it's a screw-mount, and it is about 42mm diameter, then it is almost certainly M42 or Pentax screw or Practica screw which are really the same thing. and, yes, you can get an adapter (Google "M42 to K mount")but read the threads here about the cheap Chinese adapters. If it's a screw-mount and it has a switch (or slider) marked A-M or Man-Auto then it could be useful. However:
You are advised to get a genuine Pentax adapter. The Sigma lenses were made for Sigma by that well-known firm "Lowest Bidder". You may have gotten a good one, or you may not.If you get the genuine Pentax adapter, then you can keep the adapter, and get some of the really good Pentax M42 lenses.
OTOH - if its a bayonet mount lens, the chances of it fitting a K7 are somewhere between zero and non-existent
Water can wear away a stone - but it can't cook lunch
X-5
istDS
K2000
P50.
Lenses Digital: 50-200, 18-55 KAF: 28-80.
Lenses KA & K: SMC-KA f2.0, SMC-K f1.4, SMC-K f1.7 Tokina KA 28-70 , SMC Pentax 70-210 F4, Sigma KA 75-300 , Hanimex 500mm Mirror, and the Tamron Adaptall-2 stuff.
and then there's all the M42 kit, and the accessories ...
X-5
istDS
K2000
P50.
Lenses Digital: 50-200, 18-55 KAF: 28-80.
Lenses KA & K: SMC-KA f2.0, SMC-K f1.4, SMC-K f1.7 Tokina KA 28-70 , SMC Pentax 70-210 F4, Sigma KA 75-300 , Hanimex 500mm Mirror, and the Tamron Adaptall-2 stuff.
and then there's all the M42 kit, and the accessories ...
Posted 18/05/2011 - 22:32
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thanks for your advice greatly appreciated, it says on the barrel that it is P/K A-R fitting. Too new to add images yet.
Posted 18/05/2011 - 22:47
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blackwill wrote:
thanks for your advice greatly appreciated, it says on the barrel that it is P/K A-R fitting. Too new to add images yet.
Careful. If you get it on, you might not get it off. The-R stands for Ricoh i believe, which had an extra pin. If this is the case I believe they worked fine on manual focus bodies, but the pin jams on autofocus bodies.thanks for your advice greatly appreciated, it says on the barrel that it is P/K A-R fitting. Too new to add images yet.
I've no first hand experience. No doubt someone will come along who has. In the meantime don't try to get it to fit.
Posted 18/05/2011 - 22:49
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Be careful, the P/K A-R normally means it is made to suit both Pentax KA and Ricoh K mounts. However since Pentax introduced autofocus on their K mount the extra pin used for the Ricoh "A/P" setting can lock the lens into the camera body. edit Lost my fastfinger title
Barrie - Too Old To Die Young
https://pentaxphotogallery.com/artists/barrieforbes
https://www.flickr.com/photos/189482630@N03/
https://pentaxphotogallery.com/artists/barrieforbes
https://www.flickr.com/photos/189482630@N03/
Posted 18/05/2011 - 23:00
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To be honest it wouldn't fit, that's why I was asking if there was an adaptor that could be used with it. Again I appreciate the advice you have given.
Thanks,
Will
Thanks,
Will
Posted 18/05/2011 - 23:13 - Helpful Comment
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If it is as the pictures show a P/K A-R mount then it should fit the K7 without the need for any adaptor, apart from the Ricoh pin bit. The basic mount has not changed shape since its introduction. Someone else may remember, but in the back of my mind was there something about some third party lenses having a long aperture actuator lever that had to be modified
Barrie - Too Old To Die Young
https://pentaxphotogallery.com/artists/barrieforbes
https://www.flickr.com/photos/189482630@N03/
https://pentaxphotogallery.com/artists/barrieforbes
https://www.flickr.com/photos/189482630@N03/
Posted 18/05/2011 - 23:15 - Helpful Comment
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Quote:
To be honest it wouldn't fit
Well who's a lucky so and so then, as others have mentioned had you managed to lock this lens on then you would have had fun getting it off Pentax should have been well aware of this problem occouring and should have had the sense to put the AF drive somewhere else.To be honest it wouldn't fit
The reason it wont fit is the large flange thats protecting the aperture actuating lever, there is no adaptor available that I am aware of, you have four choices:
1) sell the lens
2) find a teleconverter that will fit and use it as a longer lens, or fit extension tubes and use it for macro.
3) remove the mount and disable the pin which fouls the AF screw and then grind off the flange thats preventing it attaching to your camera (very do-able).
4) keep the lens until Pentax release a body that does not support the screw drive AF, of course you probably still need to grind off the flange.
Sorry but its all a bit negative but look on the bright side, you didn't manage to get it on and cause yourself an awfull lot of grief.
Posted 18/05/2011 - 23:17
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I am a complete novice, but I noticed that the aperture actuator is longer than my other pentax lenses.
Posted 18/05/2011 - 23:27 - Helpful Comment
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it may well be longer and thats the reason the flange is bigger to protect it, the lever may need shortening too then.
Depending on what you paid for the lens and how good its rated (IQ wise) then it may be worth tackling the conversion, personally I would mark it down to experience and move on, ask the seller to get you the adaptor he claims is available or ask for a refund.
Depending on what you paid for the lens and how good its rated (IQ wise) then it may be worth tackling the conversion, personally I would mark it down to experience and move on, ask the seller to get you the adaptor he claims is available or ask for a refund.
Posted 18/05/2011 - 23:53
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fatspider wrote:
it may well be longer and thats the reason the flange is bigger to protect it, the lever may need shortening too then.
Depending on what you paid for the lens and how good its rated (IQ wise) then it may be worth tackling the conversion, personally I would mark it down to experience and move on, ask the seller to get you the adaptor he claims is available or ask for a refund.
Thanks Fat spider I'll take the advice and chalk it up to experience.it may well be longer and thats the reason the flange is bigger to protect it, the lever may need shortening too then.
Depending on what you paid for the lens and how good its rated (IQ wise) then it may be worth tackling the conversion, personally I would mark it down to experience and move on, ask the seller to get you the adaptor he claims is available or ask for a refund.
Will
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