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DT 18-250 and Minolta 100-200mm
Topic Started: Mar 16 2011, 09:28 PM (2,080 Views)
robinc2005
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Sorry bros, correct me if i'm wrong. Is it the same theory as:
1. DT Lens on crop body @ 250mm = 250mm
2. Minolta Lens on crop body @ 200mm = 300mm (With 1.5 Crop Fact)
??Correct?
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blaz7
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All should be multipled by the crop factor.
Edited by blaz7, Mar 18 2011, 09:44 AM.
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robinc2005
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blaz7
Mar 18 2011, 09:40 AM
All should be multipled by the crop factor.
You mean even with DT lenses on crop body should be multiplied by crop factors as well? if that is 250mm on crop body should be 375mm instead?
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blaz7
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Yes, it should be 27mm to 375mm
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robinc2005
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blaz7
Mar 18 2011, 11:24 AM
Yes, it should be 27mm to 375mm
But how come DT18-250 more far when we look at the photo?? Still don't understand. Sorry for noob questions...
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blaz7
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From what the articles explained, it was something to do with what they call focus breathing, but when i tried it at focus to infinity, 250mm was indeed longer than 200mm. You can trying reading the articles posted by cjng.


Look under the handling part.
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ghostfit
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robinc2005
Mar 18 2011, 11:17 AM
blaz7
Mar 18 2011, 09:40 AM
All should be multipled by the crop factor.
You mean even with DT lenses on crop body should be multiplied by crop factors as well? if that is 250mm on crop body should be 375mm instead?
Yes, that 250mm is the focal length regardless on FF or cropped body ...but on a cropped body it will give a 'field of view' equivalent to 375mm on a 35mm format (FF body)

I was stumped by all this too when I went digital. :D

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