Opinions on gamma

[ufoufo512]

So, now that we have virtually perfect screen resolutions and refresh rates, I think we need to put our attention to color reproduction. Why? Well, because otherwise we don't have anything to adjust, I guess 

Anyway, I would like to hear other experiences, opinions and tricks. I'll start. I use AMD 6450 with pretty used Well Gardner K7000. There are some texts faintly burned in the monitor and I have changed aging caps with new ones, so all things considered the monitor is ok.

My problem is following. Different games need a bit different adjustments on brightness /contrast (this is ok),  but some games I seem never to get as they should look in my opinion. I understand that this can be subjective, but still some games look too heavy, no matter how I adjust brightness and contrast.

For example, try Mortal Kombat and see if there is any detail on the player character info (that are displayed while the game is in attract mode) screen texture or in the various backgrounds of the actual kombat arenas. Just found the gamma setting in Mame. Setting "Gamma" to 1.2 in Mame seems to make the tones more as they should be. Again IMO. The other game that always seems too heavy and dark in Gauntlet, even with gamma 1.2. My questions are:
1) What are your opinions? Do you notice any issues? Any special case games?
2) How to deal with it? Any systematic methods, info, links?
3) Will Mame's gamma setting easily clip colours?

Let's discuss!

Edit: And I used J-PAC as well, if that matters. There is a video amplifier there, or is it?

[cools]

I use 0.7 for everything. Just checked with MK and it displays correctly here on 0.7. 1.2 is way too high unless your monitor is badly set up.

Doesn't work for all games however. Super Contra for example needs the brightness and contrast adjusted quite dramatically to display properly.

[ufoufo512]

Ok, good to know. I am a bit surprised, have you done anything to Mame's brightness and contrast controls?

An to clarify, I have those at default settings myself. When I talked about brightness & contrast previously, I meant the physical potentiometers on the monitor.

[Calamity]

Why? Well, because otherwise we don't have anything to adjust, I guess 

 

Yes, definitely, we all need to have adjustements to mess with.

Edit: And I used J-PAC as well, if that matters. There is a video amplifier there, or is it?

Well, in my experience with the J-PAC, I always needed to modify the contrast potentiometer on the monitor board. Both of my Hantarex MTC 9110 came adjusted for a PCB and they looked fine with it. But when I plugged the J-PAC the picture looked badly burnt, it made almost impossible to read texts in Windows, and colors in games were way off. I could fix it, as I said, reducing the contrast on the monitor board. On my friend's Hantarex, additionally to the contrast, we also needed to adjust the color pots on the board that's at the end of the tube's neck. After that, colors look quite good leaving default MAME gamma. Of course I don't mean there's room for improvement. I'm just happy how they are now.

[cools]

Ok, good to know. I am a bit surprised, have you done anything to Mame's brightness and contrast controls?

No. The same setting on LCDs and CRTs I use.

It's not perfect by any means (NeoGeo games are better at 1.0 but it's not really noticeable, Konami games definitely should be lower - 0.55/0.6), but it fixes just about everything whilst not breaking anything badly. Good enough to use across the board.

Nice easy example - Ghouls N Ghosts. The background trees and mountains should be dark.

[ufoufo512]

Great info, thanks. Keep it coming. So, I think that I can at least conclude two things:
a) games from the different manufacturers might need a bit different adjustments. b) Jpac amplifies the signal to quite "hot". I found few threads here on arcadecontrols.com on talking about it. General consensus is to lower contrast and/or drive to compensate.

So I will experiment a bit more. Lowering contrast helps somewhat, but the tone range from shadows to midtones is still somewhat crushed, destroying the depth and 3-dimensionality of the old 2D bitmap art.

Gray balance seems also too greenish on dark tones, maybe that is origin of my problem. Is there a way to adjust cut off and drive and still stay sane and / or not to make things worse? 

[cools]

Use a known good source - I.e. a PCB.