I have an image I need to print on black shirts but it was given to me as a grey scale. I was wondering when I set it to halftone what the best settings for degrees and lines per inch would be if I were to use a 255 screen with out it coming out pixelated.
You want 4 lines of mesh to hold 1 dot, White should go threw a 90-140 mesh easy, we use 140 mesh for white on black here. 255 is WAY to fine a mesh for white ink. even reducer or soft hand won't cut it enough, Unless your really skilled. the degrees of the lines usually are set in your RIP software or postscript, 0,45,105 to reduce the moire. Corel photo paint has a "tone curve " tool that works wonders with halftones and grey scales you need when you need to print white ink on black tees.
NUTTZ
if you you use two screens (156 and 230) you can reduce the white ink for the 230 to make it easier to print. Halftone dots don't need to be as opaque as the solid areas. I've even printed white halftones with non opaque ink when I wanted a soft looking glow or shadow.
Recently I've been experimenting with 45 lpi dots on 156 mesh and I've been pleased with the result. As Nuttz said above, 156 is way easier to print with, opaque ink or not.