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01-11-2008, 07:30 AM   #1

which Lens focuses faster?

The DA* 16-50 f/2.8 or the DA 16-45 f/4?

I think the DA 16-45 is faster. Or, maybe because I can hear it focusing, unlike the DA* 16-50 which is virtually silent, I only think it's faster.

I does seem that when I use the DA*, there seems to be a hesitation before the focusing actually begins????

01-12-2008, 03:54 AM   #2
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I would imagine a faster lens to focus faster ... but this isnt always the case . For example some F1.4 are quite soft at the 1.4 aperture so they dont focus accurately so it takes more time to focus accurately ... Maybe I am wrong.
01-12-2008, 05:05 AM   #3
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Da* 16-50 definitely autofocus faster than Da 16-45 with updated firmware. Back focusing only happens with near focus in low light for my copy.

It is silent and working well with candids alike.
01-12-2008, 06:02 AM   #4
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It depends

on several factors IMO. The brighter the lens is there is somehow more trouble in focusing (due to full open contrast detection). So somehow F4 lens should focus faster that F2.8 (given it has enough light) but OTOH it is vastly related to gears in lens etc. For me 16-45 is very good (and no diff from FA35 or FA50 although these are at least 2 stops brighter- so contrast detection strongly depends on overall lighting I guess)
Best and happy shooting, JR


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