Ok I took my time and plugged my MegaDrive to a TV card. I'd love to make use of RGB capture card instead but those are prohibitively expensive.
Your comparison again, for reference:
Except of seeing that both old and new builds are wrong (that makes all PC emus wrong too I guess) I don't really know how to calibrate this. The reference image heavily depends on TV card settings. I haven't seen anyone doing RGB captures from the real thing either. The old build might look better to you but it's levels are wrong compared to levels of pixels with shadow/hilight operators applied.
Well the newest build looks the darkest of the lot, and futher from the top picture than the rest. The previous one at least had the shades a bit closer and you could see the brown on the rocks better, but they are close to the same. The frame dumps have the shadow detail crushed too. Even that purple bar at the top is almost pulled to black. The text for the score has a bright spot in the center but then falls off to the point you can't see the edges. It is not just a dark LCD as you say or ALL shades would be dark together, but smooth. If you look at the rocks in the example the tan highlights are as bright as the other builds/example but the shadow detail is crushed. This is because the gamma curve is suppressing darker shades for some reason.
In the example I did I tuned the colors on the second image in a paint program to match how they look on the actual LCD, not a frame dump as that looks a bit different. Try it on your Pandora unless you have custom settings it pretty much looks like my second pic(I just checked again). I have the LCD gamma as default which is just a linear ramp. I have the brightness set to one notch below the brightest. Yes I can tune the LCD gamma to improve but then it will screw up all of the other software that doesn't need a gamma change. I don't know if it is possible for the emulator to read Pandora custom gamma settings. Even some kind of script that loads a setting then returns it back after you exit would work.
I am not sure why you say the older one was more "wrong" when it looks better. It looks like what the shadow operator does is get rid of shadow detail. I am not sure how that is better, that looks more different than your first pic (although I admit is a bit TOO washed out). The top image doesn't crush shadow detail like the Pandora build does (used the rocks, score text again as example).
If I did do an LCD gamma tweak so that it looks better could you use those numbers for your table? I know you couldn't do it directly but maybe they could be used as a reference?
Edited by DaveC, 22 September 2010 - 03:32 AM.