I received my unit for testing earlier this week but wasn't able to do any testing until this evening. This is an impressive little tool. The integration is pretty much seamless. My unit was missing the screw posts to secure the adapter to the monitor but being a test unit this isn't an issue. Bottom line, it works and works well.
Monitor used for this test: M170EN05 LCD, 17" AUO SXGA Max Resolution 1280x1024
Resolution used in this test: 480x640
MAME was paused for pics, shading on pause is 10%.
Galaga left to right (or top to bottom depending on which device you're reading the forums on) we've got no scan gen, scan gen red full up, scan gen middle, scan gen red full down.
Same deal, no scan, red up, half, red down
I really didn't like the green too much so I turned the red full up and left it, just looked "more right" to my eye but YMMV. The pot isn't a bad idea and I do notice a huge difference but I think that if you just went with a strong red and ditched the pot I wouldn't mind at all. Dodonpachi shown without and with. The scan gen really takes the edge off and gives the bullets a nice warm glow rather than being little pink squares.
I played around with some horizontal games as well. It does take the edge off and adds a richness to the background. This is a great project and is heading in the right direction. Crafty, you've got a real winner here. I'll get it tried out on some other platforms but for right now I'm just having a blast playing and almost immediately forget it's there until I disconnect it and then I immediately miss it.
One thing that I did notice right away, my MALA skin looks like hot garbage with scan lines. This is not an issue with the scan gen at all, just a result of designing the art based on how it would look on the stock monitor. If you have an eye for that kind of thing and are building with one of these in mind you're going to want to design your layouts/skins/whatever to capitalize on the new presentation you'll be getting out of the monitor with this scan gen. Makes me want build a dedicated vert cab.