Does flange distance impact sharpness?

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Well-known member
Supporting Member
Here's are 2 accessible articles on field curvature and how the quality of lenses is measured, with key terms etc

Here's are 2 accessible articles on field curvature and how the quality of lenses is measured, with key terms etc

Both worthwhile articles to help keep the head from spinning.


I'm no expert, but most of my reading suggests the short flange mounts and large diameters help mostly with wide angle lenses. However, I suspect the single largest contributor to increasing lens performance lies with newer computer modeling and fabrication techniques. Sony has figured something out in the last 3 or 4 years and every newer, high end lens they release seems to have near benchmark levels of performance. I don't keep as close a watch on Canon or Nikon, but I suspect they're recent offerings are set apart from previous ones as well.


Well-known member
Excerpt from this article shared by Jim Kasson across at the dpr Z MILC forum to do with understanding the more superlative attributes of the "best" lenses. This statement opened my eyes to yet another variable to be compared in MTF curves: "... But even more important, the large area under the Primo 70 MTF curves denotes a natural sharpness that includes the full range of high and low frequency components."




Active member
I recently asked the folks running Greys of Westminster YouTube channel via live chat about why the Z lenses are significantly sharper than f mount glass.

They implied that the larger Z mount with the 16 mm flange distance as opposed to the 46 mm flange distance on the f mount is a big reason for it. Also, that Nikon can construct & design similar focal length lenses better to get more sharpness.

I want to know if all things being identical or very similar, will the 500pf be sharper on say a Z7 compared with its performance on the D850?

I know Z7 has the advantage of auto lens calibration & IBIS...

Also, does flange distance make an impact?
What do you think folks?
A short flange distance solves most lens design problems.
Except the angle that the light that reaches the sensor towards the edges becomes a little more distorted.
Because the FTZ adapter corrects the flange distance to 46mm - The 500pf on a Z camera will be almost identical to that on a D850.
I still prefer my D850 bodies over my Z cameras - maybe the Z9 I ordered will change my mind. 🦘