XE lightgun: Real 7800 vs MiSTer, XE vs Sega Phaser, offset, accuracy, adapters, etc.

[+SmittyB]

The 7800GD has the option to somewhat calibrate the gun on the NTSC version of Crossbow as part of its cheats functionality, but besides that no.

The way most lightgun games on the 7800 work is by flashing the screen white and then using strict timing to calculate where on the X axis the gun is pointing. There's a limit to how accurate this method can be on a relatively slow system like the 7800 and there's a good chance the accuracy will depend on the specific console. It also doesn't help the developers hardcoded their own offsets into the game instead of allowing for manual adjustments.

Best you can do is make sure the brightness / contrast of your TV is high enough for the gun to more easily see it, make sure the lens is clean, and sit as square-on to the TV as you can.