40-150 PRO focus breathing?

CrisPhoto wrote:

Anders W wrote:

...

If by "growing" you mean that the background is magnified more as you reduce the focus distance, it is not really confusing if you consider what I say in my reply to whumber here. As I pointed out in my earlier reply to you here, the formula I provided gives you the focal length of a thin lens having the same reproduction ratio and linear FoV as the target lens when both are shot at the minimum focus distance of the target lens. But a thin lens with a focal length of 47 mm has an effective focal length (see my reply to whumber here for the conventional definition of "effective focal length"), when shot at a focus distance of 188 mm of 47(1 + R) = 47(1 + 1) = 94 mm, and the effective focal length is what determines the angle of view. So it is not surprising that the 60/2.8 macro gets a more narrow AoV as you reduce the focus distance in spite of the fact that its focal length stays more or less constant.

Hi again,

thanks for the good reading. As a good guy, I have updated the table slightly (17,3mm width instead of 18, thin lens instead of effective)

Regarding the sharpness loss, last time I browsed my photos very fast and took a bad example (different focal plane and not very close).

If you would go closer, the differences get more obvious, to the point that you realize the missing sharpness in the EVF. In the next sample I went as close as I could (R=0.2) and took the Oly 14-150 shot three times because I could not believe how bad it was ...

Thanks! That's certainly a convincing illustration.

Close up near maximum magnification of 0.2

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OM-D + Sam7.5, O25, O60, O75
O12-40, O40-150, P 14-140