Converting Chinese laser to run 8 bit engraving

[James MacNab]

Hi All,
I was woundering if it is possable to convert a Chinese laser using lasercut 5.0 to something that will let you engrav in 8 bit. Has any one done this or is it possible? Machine's bought in the US do it so why can't we convert others to do the same thing. Looking forward to your ideas.
Jim

[Darren Null]

You only get 'sort-of' 8 bit engraving on any laser, and then only on very specific materials, like wood, where you can burn lightly for the greys and burn a bit harder for the darker shades.

If you're up for writing your own printer driver, I'm sure it's possible to do 8-bit burning. Easier by far is to run the image through a decent dithering program like photograv and fake the shading in 1-bit. That'll work on everything, and to be honest, 8-bit isn't all that...on wood, for example, 8-bit burning really emphasises the grain, which can totally kill the image. You're proof against that with 1-bit, and it'll work on anything.

[James MacNab]

Darren,
Thanks for the heads up. I was afraid that was the answer. There must be some gee wis kid out there who could write something that would work. Any way thanks
Jim

[Darren Null]

Thinking about it, if you can burn at different speeds and powers on your current laser using different colours, you could fake it to a certain extent:

Say, you have 4 colours you can specify (to make the explanation easier, black, red, green, blue (in that order on your driver, to keep things simple)).

In photoshop, turn your image greyscale; then into a gif of 4 colours.

Then using select --> colour range; select the darkest colour, and replace the colour with black.

For the next darkest shade of grey, replace with red.

And so on until you have your colours filled.

Then print the image, and in the colour/power bit (usually in the printer driver menu, manually select different power values for your 4 colours, and print. 100% for black, (say) 80% for red, 60% for green and 40% for blue. And there you have it, fake greyscale.

It's no bloody good for wood though; like I say, it can really emphasise the grain which can kill your picture. A good dither, and you're burning all the dots at the same power, which doesn't emphasise the grain and you end up with a better image.

The only things I can think of that 8-bit is useful for is 3D (which sucks, frankly) and lithophane. And there, you can use the 'select colour' method. Even if you can't run different colours/powers/speeds, you can select the individual colours, and save each to a separate image (making sure that all the images are the same size) and burn/adjust the speed/power manually for each pass. It would be massively boring though.

Or you could try to blag the sales rep that it's a hugely needed feature for the laser and he needs to get the boys in China coding it in pronto if they want to sell millions.

[Rodne Gold]

I think photograv would be a LOT cheaper and less hassle than trying to write your own greyscale type engraving driver.
I have also posted a way to use Corel Draw to simulate Photograv...seartch for alternatives to photograv.

[John Barton]

I think photograv would be a LOT cheaper and less hassle than trying to write your own greyscale type engraving driver.
I have also posted a way to use Corel Draw to simulate Photograv...seartch for alternatives to photograv.

Do you have a link to that post? Yes I will search for it as well :-)

Thanks,

John

[Darren Null]

Now with 2 different choices of automation!
http://www.sawmillcreek.org/showthread.php?t=91076
http://www.sawmillcreek.org/showthread.php?t=91167