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Dave Chase
01-29-2007, 7:22 PM
Hi Gang,

Here is another "newbie" question about engraving photos. I am trying to engrave a photo onto some teal color anodize. I have the photo converted to a grayscale and then inverted so as to obtain the negative. The picture comes out great except that when you hold it under a light you can still see portions of the blue anodize in the lighter sections (ie: sections where the laser didn't burn as strong) What am I doing wrong? Is it a brightness adjustment? Contrast? I'm confused....

BTW, I'm using X3 and do not have Photograv. I'm using a Versa laser and am limited to the factory driver/settings.

Thanks

Joe Pelonio
01-29-2007, 7:36 PM
Hi Gang,

Here is another "newbie" question about engraving photos. I am trying to engrave a photo onto some teal color anodize. I have the photo converted to a grayscale and then inverted so as to obtain the negative. The picture comes out great except that when you hold it under a light you can still see portions of the blue anodize in the lighter sections (ie: sections where the laser didn't burn as strong) What am I doing wrong? Is it a brightness adjustment? Contrast? I'm confused....

BTW, I'm using X3 and do not have Photograv. I'm using a Versa laser and am limited to the factory driver/settings.

Thanks
I'm not sure I understand the problem, the teal is "black", and anything 100% black on the photo would laser white. Anything grey in the photo should still show as partially teal. A more true duplication of a B&W photo would have to be done on black annodized aluminum.

Dave Jones
01-29-2007, 7:44 PM
Since you don't have Photograv, I am guessing that you are using the driver to convert the grayscale into a haltone or dither pattern?

What dpi is your laser driver set to?

On my Epilog if I try to do anodized aluminum at too high of a dpi, then single dots will often come out "underexposed" and not turn the anodize white, while clusters of dots do turn it white.

Try a test at a lower dpi and see if it makes a difference. I get around it by converting to a dithered image before going to the driver, either in Photograv or in Photoshop (Photopaint can no doubt do it to). I convert at a lower resolution than the driver setting. For example I convert the image to a dither at 300 dpi and then engrave with the driver set at 600 dpi. This causes every engraved dot on the aluminum to be hit by 4 dots of the laser, ensuring that every dot of the original has enough power to get through the anodize dye.