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07-14-2016, 08:41 AM   #1
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shake reduction with the 28-45

Hi Guys,
just got this monster here to test and the manual says, that the SR may not work with closeups...
took a couple of portraits with closeups yesterday and seems that SR did not do it's job below 1/50. they were shot with 45mm at about half a metre.
I am not sure what's happening there. So I don't know if it's the distance or just how far down the SR is effective.
what is your take on this?

cheers
Stephan

sorry, can't post pics...

07-15-2016, 02:46 AM   #2
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It could be for optical reasons that the SR disables itself at close focus distances. That's just my hunch.

Adam
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07-15-2016, 03:53 AM   #3
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QuoteOriginally posted by zobeleye Quote
Hi Guys,
just got this monster here to test and the manual says, that the SR may not work with closeups...
took a couple of portraits with closeups yesterday and seems that SR did not do it's job below 1/50. they were shot with 45mm at about half a metre.
I am not sure what's happening there. So I don't know if it's the distance or just how far down the SR is effective.
what is your take on this?

cheers
Stephan

sorry, can't post pics...
This simply seems to be the nature of shake reduction at close-focus distances, just look at the footnotes for -any- stabilized macro lens, and everywhere it will say that IS/OS/VR will not work at macro distances. Same with our own 90mm f/2.8, it's rated for only 2.5 stops of effective shake reduction, and even then only at "normal" distances.

I reckon that optical stabilization in general is only effective starting from 1 meter or so with most lenses, and quickly drops off below that. 1/50th is still not bad since I normally keep my shutter at 2xFL or more for critical sharpness on the 645Z.
07-15-2016, 03:55 AM   #4
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I've just tried mine at 45mm and around 50cm distance and can see some correction/improvement.

I tested it (not very scientifically) by using Liveview at arms length and focusing on an LCD monitor and there's certainly more moire "dancing" with SR off.

I have a Canon setup with the 100mm macro and the effectiveness of the image stabilisation (4 stops claimed) dimishes very rapidly to zero as the subject distance decreases.

Bob

07-15-2016, 04:37 AM - 1 Like   #5
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The SR in the lens only compensates for pitch/yaw camera shake, which affect all images regardless of focus distance, but at closeup it's the X/Y camera shake that dominates as it increases with the magnification of the shot.

07-15-2016, 10:42 AM   #6
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Original Poster
AAH...
very interesting read, guys.
thanks for your feedback.
I have now completed a series of tests in daylight and can safely conclude that 28-45's SR works up until 1/25, then stops working at 1/20. that's at 45mm.
for the other thing with the distance, again at 45mm, I can say that it still works brillantly at about 45 cm, so no problem there.
I assume it was something with the switch, cause I did not switch it on/off/on when I got it , since it was already engaged. and I did only today notice that it shows a litlle icon in the finder when engaged.
so all good apparently...
cheers
Z
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