09011: Multiple arcade sets: [possible] Blue levels only reach about 222

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
09011	Color/Palette	Trivial	Always	12 days ago	3 days ago

Tester	125scratch	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	Open	OS	Windows 10/11 (64-bit)
Status [?]	Direction Needed			Driver
Version	0.272	Fixed in Version		Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	09011: Multiple arcade sets: [possible] Blue levels only reach about 222
Description	I have noticed that for a while the blue color levels in many games, mostly from the early 80s, do not reach the full blue intensity, even when red and green do, including the following drivers: galaga, rallyx, snk6502, btime (disco, lnc, mmonkey, protenn, wtennis), docastle, bankp, gberet, yiear, chaknpop, marineb, shootout, mermaid, ambush, vastar (dogfight), mystston, mrjong, liberate (not prosport), drmicro, espial, and others. This creates a slight yellow tint on the screen. This may or may not be an inaccuracy, and I noticed that this has been fixed in some drivers like pacman, mappy, cclimber, and partially btime (for Burger Time and Burnin' Rubber), and a few others. Also, I noticed that yieartf does have full blues, since it runs on Track & Field hardware.
Steps To Reproduce
Additional Information
Github Commit

Flags	Possible
Regression Version
Affected Sets / Systems	Multiple arcade sets

Attached Files

No.22563 Robbbert Moderator 12 days ago	Could be because of resistors.
No.22565 125scratch Tester 12 days ago	How so?
No.22566 hap Developer 12 days ago	Like this (yiear.cpp in this example) Then yes, max blue will have slightly lower voltage than max red or green. bit 7 -- 220 ohm resistor -- BLUE -- 470 ohm resistor -- BLUE -- 220 ohm resistor -- GREEN -- 470 ohm resistor -- GREEN -- 1 kohm resistor -- GREEN -- 220 ohm resistor -- RED -- 470 ohm resistor -- RED bit 0 -- 1 kohm resistor -- RED
No.22567 125scratch Tester 12 days ago edited on: 12 days ago	I suppose that makes some amount of sense, but I'm wondering why drivers like pacman and mappy used to be like this but aren't anymore. I always thought it was a bit of an inconsistency, and felt like since Galaga hardware is similar, it should also have higher blue values in most cases, and Galaga and Dig Dug cabinets I've played don't seem to have that issue, though I know analog video and CRTs are a factor.
No.22568 hap Developer 12 days ago edited on: 12 days ago	pacman (I mean, the pacman.cpp driver) uses resnet.h, maybe more accurate that way?
No.22569 125scratch Tester 12 days ago	I realize I haven't provided any real hardware examples, I did look for some but found them hard to find, and analog video is somewhat inconsistent anyway.