Re: [OM] Red

Subject: Re: [OM] Red
From: Wayne Shumaker <om3ti@xxxxxxxx>
Date: Tue, 02 Jun 2020 19:16:12 -0700
At 6/2/2020 03:36 PM, Moose wrote:
>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
>>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 
>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.

Ahh, so there is a reason to go for that 61mp A7R4. And down sample it to 16mp.
Sorry, couldn't help it.

megapixel up the ... WayneS
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