New DSLR - Pentax K5
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09-11-10, 10:51 AM
Join Date: Sep 2010
Originally Posted by
Obviously the reviews will be copyrighted, and I won't be nicking their graphs, but I'm quite happy to précis the conclusions and any bits of detail that seem to me to be particularly interesting.
So now we just have to wait
You're right Chris about the assumption that because a lens is screw drive it won't focus fast. It does, of course, depend a lot on the lens. Oddly enough I find that my old KAF lenses dating from the 35mm film camera days focus much faster than the more recent lenses. The Pentax KAF 50mm f1.4 and Tamron 80-210 f4.5-5.6 focus really quickly. I guess they must have fewer internal elements to shift about.
My Tamron SP90 has its own focus motor and is
slow (literally must be close to the 2 second mark when going from infinity to closest focal distance. My Tokina 28-80mm f/2.8 which relies on the D90 camera body to focus is extremely quick. I've read other cases of motorized lenses being slower than their screw driven counterparts too. You would be forgiven for thinking that because a lens has its own dedicated motor that it would be faster. Its not always the case though.
If you need any help with the translation Hin, I may be able to assist you. I can still remember how to ask where the swimming pool is and how to order an icecream in French. My linguistic skills are at your full disposal sir
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