[royal120]

Hi i have a 150w laser i am trying to laser a photo onto granite.

Does anyone know the best settings for 150w laser?

[Tweakie]

You really have to try a sample and see, then adjust as necessary.
Although this sounds negative, because the speed and power settings are linked this is really the only way.
Good luck with your granite.

Tweakie.

[Litografa]

150 Wt - chinese?

[MonoNeuron]

First you will need to drop your power to about 2% of your total output or about 10-15 watts. Your speed might be in the range of about 6" - 10" per sec. Granite slabs are all different so you will have to experiment with what works well for a particular type.

Photograv works well for granite and would take a lot of the guess work out of it for you and is a really good program and worth the money if you can afford it.

There is one gentleman here on the zone that engraves granite very well but he also says he gets free pieces of the stuff to test on and if you had to buy it yourself you would go broke. It would seem that it is very hard to get a good picture straight away.

I have engraved on granite tiles only a few times and couldn't afford any more to test on but it is certainly difficult to get a good impression.
Start off in a small corner and do some tests but don't try to engrave too small at first as it will look like crap. A good size to start with would be about 3" or 75mm and very simple pictures, or better still line drawings, until you get to see what settings look the best.

Make the picture look very dark after you process it as the granite will show only the light parts and vice versa with glass. With glass you need to blow out all the highlites for it to engrave well.
Processing looks completely different to how it turns out.
Best of luck.
Rich.