On 6/2/2020 10:32 AM, Ken Norton wrote:
As to out-of-focus areas, my first reaction is that I have seen how
difficult it is to capture the texture of Pine Marten fur, it is simply too
fine to be resolved adequately (on a four thirds sensor in my case). And
while I cannot speak for foxes, the dogs I have got to know over the years
certainly have exceptionally fine hair behind their ears.
I find this to be one of those things that drive me batty with digital
photography. There is a micro-contrast thing going on with the fine
mesh of hairs that the digital imaging process just turns into mush.
First, you have gone to generalizations, away from the specific lens and photo Mike and I have talked about. Fine in a
way, but ignoring some of the oddities in it that I don't believe can all be dismissed this way.
My experience is more nuanced than yours. I just looked at a bunch of my shots of furry critters. Yes, there is a
spacial frequency at which individual hair resolution goes mushy. But, it is consistent within any given shot, not
randomly distributed. There is also DoF softening, but again, it follows gentle "rules" with distance.
However, not all hope is lost.
The Canons do a good job if you can overexpose the midtones by a full
stop. The problem with the Canon CMOS sensors is that all the
microcontrast is preserved in the highlights. Older Nikons were even
worse. The 4/3 Panasonic sensors were more of a mixed bag with some
being quite good (7mp and 12mp) for microcontrast, and the rest being
a bit questionable. The CCD sensor in my E-1 is quite good.
Surprisingly, the 24mp sensor in the Sony A7 II is surprisingly
exceptional.
The point is that it's not a resolution thing. It's a microcontrast
thing. The fineness of the hair is beyond the resolving ability of
pretty much every commonly available camera system.
Once again, it depends on magnification. I've got plenty of shots where individual hairs or feathers are clearly
resolved. Get further away, crop more, and that's less likely.
The Topaz apps, BTW, do seemingly impossible things in finding the hidden details in the mush (or, possibly, making up
highly believable detail.) "Do you believe in Magic?"
The resolution can
be simulated, but mostly any visible hairs or texture are not directly
that of the hairs themselves but of the interference pattern and/or
aliasing that occurs between the hairs and the pixels.
I believe most of the problem we actually see is a result of the Bayer array demosaicing. What you are talking about is
likely true, but masked by the worse effects of the Bayer system.
Tack a pelt on a wall, back off to the point where the mush happens. Then use an OM-D body with HR mode. Shoot in HR,
then downsample to sensor size, compare it to the regular shot, and there's all sorts of better detail. Ctein figures
that about half of the inherent sensor resolution is lost to Bayer demosaicing.
I mention only Oly because I don't know which others do HR and how they do it. Oly samples every sensel location with
each color sensel, so color is direct, not calculated. The difference is not subtle.
Alternate View Moose
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What if the Hokey Pokey *IS* what it's all about?
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