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Terry Wade
11-13-2022, 2:22 PM
I have a client that has given me 2 files to engrave on 8 cerakoted blades 1 on each side. When a ran a test before engraving the blade itself I get a shadow along with the logo which totally unacceptable I know that it will affect the cerakote finish. I have taken both files into other software and deleted the backgrounds and I still get the shadows. How can I get rid of the shadows?

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Bruce Volden
11-13-2022, 3:04 PM
Terry,

A stretch here--I have had that happen also with my CO2 on wood. I had to bring it back through my Corel and convert it to a B/W 1 bit file.
Seems there existed a greyscale in the file (absolutely not visible to the eye on screen), laser thought otherwise.
Like I say-maybe a stretch.

Bruce

Kev Williams
11-13-2022, 10:50 PM
Terry, correct me if I'm wrong: You're fiber lasering this from a customer supplied bitmap-?

2 fixes:

1) if the bitmaps (pictures, actually) are large enough and clean enough, CorelTrace may be able to create a reasonable vector file--

--if that doesn't work out...

2) in EzCad, when you import bitmaps, it will have a bounding-border, which is evident from your sample photos. Even if the background appears to be ghost-white, EzCad will STILL engrave a halftone 'white' background...

There is a fix for this :)

When you have a bitmap selected in EzCad, the left side of the screen will show the bitmap editing menus,
looks like this below.... What you're needing to do is click on the "EXTEND" button shown--
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This will take you into another menu screen--
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--notice what I've circled, make your screen look just like mine,
CHECK the 'Disable Mark Low Gray Point' box-- when you do, the box next
to "0-255" will now allow you to enter a number... note that
I've entered "30"...

WHAT THIS FUNCTION DOES, best I can figure out how to explain ;) --
is it lets you choose where the cutoff-point is for engraving grayscale colors
based on a basic 256 color scale. The number 30 I entered is just a starting point,
as you need to experiment to find what works best with the image you're using.
But what will happen is, anything EzCad sees as a "numerically" lighter shade of gray
than the number you entered, it will ignore those shades---

put another way, "30" out of a 256 shades of gray works out to roughly 12% black, so anything
EzCad sees as less than 12% black won't engrave. :)

Now, everything else to do in EzCad when engraving bitmaps, just play around and see what happens!
but THIS problem me and my BIL had when he wanted to engrave a rendition of his arm tattoo on
a knife, and I got the same problem, and I just figured it out by trial and error!

--try it, let us know how it comes out! :D

Terry Wade
12-06-2022, 12:08 PM
Kevin I want to let you know that I finally got another job to do that included a jpeg from the client and after some minimal clean up of the file I imported it into ezcad and made the setting changes that you suggested when I ran a test run it was perfect no shadows. I want to thank you so very much you are a wealth of information and really appreciate you!