FOV?

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Harald
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FOV?

Post by Harald »

Hi there good people,
One quick for you...
If I take an image at 4x magnification, does that mean that the FOV is 1/4 of the sensor size?
Kind Regards
Harald

Lier Fotoklubb / NSFF
AFIAP / CPS
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rjlittlefield
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Post by rjlittlefield »

Short answer: Yes

Discussion... It depends on what you mean by "4x magnification". In this forum, it usually means "4X total optical magnification, from subject to sensor". With that meaning, of course FOV is 1/4 of the sensor size. But with microscopes, people who use the afocal method sometimes say "magnification" to mean just what the microscope is set for, ignoring the effect of other optics. In that case the total magnification from subject to sensor would probably be more than 4X, and the FOV would be correspondingly less.

--Rik

Harald
Posts: 637
Joined: Fri May 13, 2011 10:33 am
Location: Steinberg, Norway
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Post by Harald »

Thanks Rik,
Equipment used: EOS 7D with MP-E65 @4x
Kind Regards
Harald

Lier Fotoklubb / NSFF
AFIAP / CPS
BGF / GMV
http://www.500px.com/blender11

rjlittlefield
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Post by rjlittlefield »

Harald wrote:Equipment used: EOS 7D with MP-E65 @4x
The MP-E 65 and all the other macro lenses that I know are marked in total optical magnification. So with those, definitely FOV = 1/4 of sensor width.

Of course if you add other lenses or extensions, then the same setting of the MP-E ring actually gives some different magnification.

The most reliable way to know for sure is to just measure it, by photographing a ruler.

--Rik

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