Teleconverter advice

RobE17 · 2009-03-28T15:44:14+0000

Hopefully a quick query... I'm thinking of purchasing a teleconverter for my airshow trips but how will they affect the images? For example with my K20 I normally use centre weighted metering and between +5/+1 EV and for propeller aircraft an ISO of 100 and a shutter speed of 1/350 or 1/500. For jets the ISO is 400 and shutter speed of 1/1000 The mode is always on TV. Can someone explain to me that if I was to use a 2x TC then if I loose 2 stops of light how would I change the settings described above to obtain a correctly exposed image? Likewise if a 1.4x or 1.7x TC was used what would be the expected effect and how would I rectify this? I would probably be using a TC combined with a DA*300mm or a zoom lens up to 300mm. Regards Rob

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Plus Member womble womble

7661 posts
17 years
Hertfordshire,
mostly.

Posted 30/03/2009 - 20:13 Link

gartmore wrote:
I have one TC, a Pentax SMC-A 645 2X, other than the loss of speed you wouldn't know it was there but you would expect that from one that retailed at £500 wouldn't you?

Kris Lockyear
It is an illusion that photos are made with the camera… they are made with the eye, heart and head. Henri Cartier-Bresson
Lots of film bodies, a couple of digital ones, too many lenses (mainly older glass) and a Horseman LE 5x4.

Mike-P Mike-P

13627 posts
18 years
Hythe,
Hampshire UK

Posted 30/03/2009 - 20:26 Link

beginner wrote:
I don't know about anyone else,but I find converters /adapters work best on Prime lenses!.....on zooms I think the image quality is effected for the worse!......only my opinion mind!

I have found this to be true as well, the only reason I tried the Tamron on the DA* 16-50mm was because it's the only SDM lens I have and I wanted to verify it worked.
Saying that both the 1.4x and 2x Sigma EX converters do work very nicely on the 70-200mm f2.8.

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