Focus question and advice please!

Started 2 months ago | Questions thread
JimKasson
JimKasson Forum Pro • Posts: 24,918
Diffraction considered

JimKasson wrote:

Here's a set of curves that I just worked out that approximate your situation.

I plotted the size of the blur circle vs distance for four f-stops, assuming a sensor with the pitch of the GFX's and 100% fill factor (a little high). I assumed the lens was perfect (not even diffraction) and was focused at 30 meters.

You can see what happens to the blur circle as the subject gets close.

Now I'll add diffraction and take into account the GFX's fill factor:

You can see that f/16 is better than wider apertures that have less diffraction for subjects closer than 15-20 meters, and is at least as good as the other apertures at infinity.

Here's what happens when you focus at infinity:

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