selmslie wrote:
But as the information is lost, so does is sharpness. And as more pixels are compiled into a single pixel, we should see a darkening of highlights, even specular highlights. They should not get brighter, but they do.
It's not just happening in Capture One.
I have figured out what is happening in the two photo viewers. It relates to the comment above.
When I view the full image on my 2k display (23½" wide, 82ppi) with the Windows Photo Viewer or in Capture One, the complete image covers a width of about 17", about 1390 pixels out of the 1920 for the full screen. The numbers are a little different for the 4k display but the same thing happens.
In order to get 6000 image pixels down to 1390, it has to be downsized by 1390/6000 or more than four times in each dimension. Detail and sharpness is lost during this downsizing and the highlights are darkened. But the image will actually have about the same tonality and sharpness of a 17" wide print.
As I zoom into the image, the highlights appear to get brighter because there is less downsizing.
But zooming in also shows how a larger print would look. I can only make a 16x24" with my P900. A print that size would mean that anyone looking at the print will probably view it a normal viewing distance slightly greater than the distance at which I view my desktop monitor. For a larger print a normal viewing distance would render about the same character and apparent highlight brightness.
The Capture One export is different issue. During export it offers the option for additional adjustments (Lightroom might also offer this):
But doubling down on the sharpness already baked into the image (I normally leave it at Capture One's default) may not be a good idea.
I tried several alternatives - No Output Sharpening, Output Sharpening for Screen, Output Sharpening for Print and Disable All. They all do something a little different. Output Sharpening for Screen works well when reducing the image size for viewing but Output Sharpening for Print does not work well for viewing.
It seems that the best alternative for printing is use the full image, JPEG or TIFF makes no difference. I will have to do some more prints to see if there is any difference between No Output Sharpening and Output Sharpening for Print.