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40-150 PRO focus breathing?

Started Jul 8, 2015 | Questions thread
whumber
whumber Veteran Member • Posts: 4,371
Re: 40-150 PRO focus breathing?

CrisPhoto wrote:

From the numbers,the macro lens seems to have 22% focus breathing.

But a quick focus test is showing me that the background is growing 30% when I focus from 30cm to 10cm. This would be -30% focus breathing in our table, isn't it? Confusing ...

Like I said earlier in the thread, the equation Anders used is only valid when the thin lens assumption is valid, or to put it another when the distance between the principle planes is much less than the subject distance.  For some lenses this can be a reasonable assumption, but it's not reasonable in any general sense.

 whumber's gear list:whumber's gear list
Fujifilm X-T1 Olympus OM-D E-M1X Olympus E-M1 III OM-1 Olympus M.Zuiko Digital ED 60mm F2.8 Macro +10 more
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