As I have mentioned in some previous posts, I just have never seen lasered glass look as good as sand blasted. I tried every trick mention here, wet paper soap, power, DPI, etc., but never even got close to any thing I can do on the blaster. I did settle for the fact that creating the mask on the laser works nicely and saves time.
I recently purchased some PhotoBrasive Laser Mask from Laserbits to try it out.
It works pretty well, although I find it difficult to get it to not wrinkle on a curved surface. I had the same difficulty with Raysist photo mask, so no biggie.
I did a couple of jobs using the laser to do the mask and blaster to finish as usual, but decided to play with the laser one more time. I jacked up the setting to 80% power and 100% speed which I would never do on glass because it's just too much power. The DPI on the laser was at 500. I made two passes at that setting with the mask in place and lo and behold, it came out fairly well.
It still is not blast quality and you can't get any deep cuts, but passable.