I don't know where to start on this, so I give it a try (Pardon me as I am a very lousy teacher and in explaining stuff).
1. When you mean bit in monitor display, a 12bit grey is more than a 24bit RGB. A 24bit RGB means each color channel (Red Green Blue) has 8bit each. A 12bit grey means it has 12bit in all channel. 8bit makes a byte and bit are actually 2 power of something (Computer technology are in 0 and 1, so it means 2 in total). In computer technology, 8 bits basically means from 0000 0000 to 1111 1111. so 2 power 8 means it got total of 256 possible digits. so a 24 bit RGB actually has 256 different color per channel (0 - 255). What does all that means? It means that your common monitor which (if I am not wrong) is 24bit display cannot replicate the same result you see with a loupe and slide projector. (
Slides has a D range much higher than that Ignore the tech spec about negative and slide D range as they are off. But you can refer to the chart inside for mapping of D range to bits.)
2. Sad right? But I discuss this with roger before and he did mentioned that even though common montiors arn't that powerful, most high end scanner that are able to scan more than what the monitor can display has a auto "Dodge and Burn" or HDR software inside that will overlay the current shadow detail when scan at certain range to allow some details to be shown in the shadow or highlight area. While it won't be exactly what you see in a loupe and slide projector, the details are at least there.
3. Monitor, scanner and printer need to be calibrated to get accurate color though the density value are different in each, the color replication still need to be accurate. To do it, we will need an
IT8 and some calibration software for that.
4. Anyway if you are interested, I feel it is easier to absorb if we can meet up if there is a next meet up or outing in the E-6 thread, you just come along and ask more verbally. I get more and more off topic everything I start typing in a thread...