First try at HDR = lessons learned.

[xpatUSA]

A pixel in the image whose RGB values are 0,0,0 will be produced as the closest to black that that the monitor can produce (the liquid crystal will always transmit a small amount of light even at black level). A pixel whose RGB values are 255, 255, 255 will be produced in the brightest shade of white the monitor can produce. All other RGB values will give light output from the display somewhere in between. It's just that the ratio of the brightest white to the lowest black is smaller when viewed on the display than it is in the original scene.

Putting some numbers to that using my monitor as an example:

Max output is 350 cd/m2 (candelas per square meter) but in my room that is too bright, so I have the brighness set lower at about 250 cd/m2. A popular figure on the web for black level is 0.3 cd/m2 but, assuming that to be the minimum setting on my monitor, it causes shadow detail to disappear for whatever reason. So I have recently set it higher - I'm guessing maybe 0.75 cd/m2. That means I have my monitor set to a contrast ratio of 250/0.75 = a miserable 333! That is 8.4 EV or stops. Doesn't bother me too much because, after processing, 8 EV is about as good as my camera gets and I don't print.

This usually results in the image looking a little dull and flat. But a thorough understanding of this difference in perception is complex and way above my head.

I don't understand that either. With my monitor, reducing the black level increases the apparent contrast in the image. But, in the literature, there are conflicting statements about monitor settings - I've seen brightness described as altering the black level for example.

So I conclude that our monitors are probably different insofar as basic adjustment is concerned. Might be fun to produce a target and spot meter it with the camera while adjusting brightness, contrast, black level in the dark.

[MrB]

Ted and Dave - thank you for your extra informative posts.

Cheers.
Philip