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12-04-2013, 03:14 AM   #1
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AF speed of (K-3 + 50-135 with SDM disabled)

According to a cosensus, the AF speed of 50-135 isn't great. People say that it is because of its not very fast SDM.
Those people who disabled SDM of their 50-135 say that the AF speed of K-5/K-5 IIs + 50-135 screw-drive is about the same as it was with SDM.
According to many reviews of K-3, it is known that K-3's AF speed has improved with screw-drive lenses. So here is a question - is the AF speed of K-3 + 50-135 (SDM disabled) is faster than of K-3 + 50-135 (SDM)?

Last edited by skyer; 12-04-2013 at 09:16 AM.
12-04-2013, 07:36 AM   #2
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I'd expect it to be noticeably faster. But that noise it makes...

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12-04-2013, 09:25 AM   #3
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It's promising. Thank you, Adam!
12-04-2013, 09:47 AM - 1 Like   #4
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How do you disable SDM on the 50-135?

12-04-2013, 10:17 AM   #5
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I'd like to know this as well, it's EXTREMELY NOISY but the slow AF is the only real drawback once you're over the size and the price. Whether it'd be noticeable I dunno though, but the K-3 screw motor is very powerful, so who knows.
12-27-2013, 06:19 AM   #6
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Is it possible for someone to upload a video shows the AF speed difference of Screw drive and SDM of 50-135mm, or even compare with Sigma 70-200mm HSM! that would be awesome!!
if it doesnt ask too much ;p
Thanks in advance!!

Last edited by souless; 12-27-2013 at 06:31 AM.
12-30-2013, 09:50 PM   #7
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I'd like to know the results of such tests too.

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