Explanation for observed optical phenomenon

[craigclu]

I'm hoping some of the learned APUGers can give me some insight into a behavior I've observed. Perhaps this is something obvious but it isn't to me.... Like most of you, I've accumulated an embarrassing amount of gear over the years; Konica/Nikon in 35mm, Pentax, Rollei, Koni-O and Bronica in medium format. I've gone through stages of lens testing, comparing of duplicate lenses, etc and have culled a few duplicates after comparing lpm, primarily. I'm supplying this info as I want you to understand that I've kept the best of 2 or 3 dupes of many lenses and am likely not looking at quirky behavior or single examples...

The effect I've noticed is that on 3 dimensional objects, I can observe a sort of depth transition softness that seems markedly different than 2 dimensional depictions on the same frame. For instance, mechanical, hard edged surfaces will be extremely sharp and edgey appearing, while something rounded in the same plane of focus and depth of field zone will exhibit a softer look that can be noticed, especially when looking for it (as I've tended to do). Is this simply a subtle, bokeh related, local contrast effect? Is it an illusion that occurs when the mind doesn't have a distinct edge to focus upon? I vaguely recall reading something alluding to this behavior 20+ years back but haven't been able to recall where it was.

[Claire Senft]

We do find ourselves in agreement: Yes you have embarassed yourself by accumulating all of that gear.