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-   -   K100D + Tamron 18-250 + Oly 1.7 tc (

dwssas Jul 29, 2007 2:19 PM

1 Attachment(s)
Just sharing. If you have the above combonation of lens, I have found them to work very very well. Never thought the Oly 1.7 would mate with the 18-250 but it does using a step down ring. Vignetting ocurrs up to 100mm and then disappears. Auto focus works as though the 1.7 was not even there. If there are negatives to this combo, except for the size, I dont know what they are. I am attaching a photo with the 18-250 fully extended.

robar Jul 29, 2007 6:25 PM

just be careful with this. ALWAYS keep the lens supported. this almost looks like an accident looking for a place to happen. i've read nothing but praise for the oly. i almost bought one for my s7000..


dwssas Jul 30, 2007 6:33 AM

Roy----thanks for the advise. This would hardly be a walk around combination but I was happy to find a use for the Oly, which I already owned, instead of being a dust collector.

bill.guenthner Aug 3, 2007 10:12 AM

Putting something that heavy on the filter mount puts a lot of strain on the zoom/focus mechanisms and on the camera mount. It's likely to cause more damage than you would save from buying a proper telephoto lens. That's just my opinion though.

dwssas Aug 3, 2007 6:34 PM

Thanks Bill for your reply. Depends what you call proper. With a little care and a budget limited I find this to be an excellent alterative to immediately just ordering the best. The whole point of the post was to help others who had similar equipment that may be obsolite. Im not trying to be difficult.

bill.guenthner Aug 3, 2007 8:42 PM

Don't get me wrong. I'm on a pretty tight lens budget myself, and I've tried this very thing, putting a Sony 1.7x converter on the front of one of my lenses. I'm just afraid if you did this on a regular basis it would break either the lens or your focus motor. The motor isn't designed to move that much mass and if it starts hunting you're liable to burn it out.

dwssas Aug 4, 2007 6:39 AM

Bill----I have to agree with you. It is a bit of a monster but works well. I will use it taking great care on rare occaisons. I was just amazed that it worked. Thanks.
Just an afterthought but when I do use it, manual focus will be in order to save the focus motor.

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