laser rastering bitmap background?

[Brie -Anne Bryan]

Boy, I am having nothing but problems lately....

I was rastering a job today on some black painted brass....one that I do all the time. The text and everything rastered fine, but the logo (which is a bitmap) did not. There is a faint half-tone/shading left in behind the image. I changed the bitmap from CMYK to RGB, ran a test and everything turned out fine...but I think it's something with my print settings.
I was recently having trouble colormatching a sublimation job and was "experimenting" with some of my print settings and although I thought I restored them all....I am thinking I must have changed something. Is there a difference between CMYK and RGB rastering in this form? I've never had a problem rastering either of them.

Any suggestions??

[Craig Matheny]

The only difference I know of is, if you are color mapping and use cmyk it will not map being the choices' are RGB and will use default settings from the first page

[Dan Hintz]

When you switched to RGB, did you verify the background was a true 255/255/255 white? Is the entire background a solid color and not splotched with a few slightly off-white areas?

[Brie -Anne Bryan]

Hi Dan,

Yes, the background when I switched was true RGB white. I did a really simple test today and rastered two circles side by side. One filled with RGB white and the other with CMYK white.
The RGB was clear in the middle and the CMYK left the same half-tone as before. Still haven't figured out why it's doing this.

[Scott Shepherd]

You should be using RGB, always. CMYK will cause issues. I've been told by several factory application people that the lasers are setup to deal with RGB, not CMYK files.

[Brie -Anne Bryan]

Hi Scott,

As a general rule, I always use RGB. I Just think it's funny that I've been doing this job for about a year and half...have never touched the artwork and all of a sudden it's doing this. I figure I must have messed up one of the settings. I just dont' know which one

[Kevin Huffman]

Yep, you will almost always have an engraving if your driver see's any color than the 255/255/255 white color. Any color but that color will be engraved some how, some way. It may not be the way you want it or if you want but it will be engraved.