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03-26-2013, 04:16 PM   #1
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croping or tammron 1.4 teleconverter

I have pentax k5. if the pexils go from 16 to 12, when the picture is crop, is this the size of picture with 1.4 teleconverter attached?

03-26-2013, 04:25 PM   #2
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By the math, the TC has 7% less field of view (more zoom) than a 16->12 MP crop
But you lose a little light with the TC.....
03-26-2013, 04:43 PM   #3
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QuoteOriginally posted by manacho2005 Quote
But you lose a little light with the TC
Also possibly some IQ as well as a result of the TC.
03-26-2013, 09:06 PM   #4
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A 1.4 teleconverter reduces linear dimension by 1.4, and thus on area basis reduces by about factor 2 (1.4x1.4). If you crop to get the same result you will reduce the pixels by factor of 2. It is (IMO) always better to use a teleconverter rather than cropping--if the teleconverter and the lens are good. (Most teleconverters I have tried are good, and if the lens is a pentax prime it also is likely good. BTW for macro work teleconverters are generally excellent.) And If the lens is not very good either way it will not be good. BTW many people would not agree with me on this. Best to try a test.

03-26-2013, 09:21 PM   #5
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both tamron 1.4x and kenko 1.5x are very teleconvertor.
They are better then cropping.
03-26-2013, 09:45 PM   #6
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Before I am tared and feathered--perhaps I should say a bit more about "it is always better to use a TC IMO." I mean if the lens is in both cases at an optimum setting and shutter speed, etc. are fine. If the TC forces you to use the lens wide open, or at too low a shutter speed then it is not advantageous. And if there is a lot of glare adding a number of additional glass surfaces may be problematic. And a TC is not as convenient! But under optimal conditions the TC is better than cropping.

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