Fiber laser question

[Terry Wade]

I have a client that wants me to engrave a logo on a pistol slide. I got the logo from him and thought I would try it on a piece of flat bar I had laying around. I'm not happy with the results so far and would appreciate any ideas how to make this turn out decent. How can I eliminate the border of the jpeg? I just want the body of the logo not the boundry of the jpeg.

image0.jpeg20220130_170402_resized.jpg
Thanks
Terry Wade

[Glen Monaghan]

You will have to use an image editor, such as Corel Paint, to select and delete the white background area. You can import the image to Corel Draw, adjust image properties as desired (resize, etc.), then Edit Bitmap to open the image in Corel Paint. Use the magnetic selection tool (adjusting the similarity value appropriately) to select the background, both around the image and inside the wreath. With all that selected, delete it, then invert the selection, save, and exit Corel Paint. The image in Corel Draw will now have "transparent background" and that part won't engrave. Alternatively, you can just open the image in CP directly and do the same things, except that when you save, you'll save to a file and be sure to select PNG format to preserve the transparency. Then import that PNG file into Corel Draw (or whatever you are using to drive your laser).

[Kev Williams]

I don't have much photo experience with my fiber's but what I HAVE found is, no matter how I manipulate a photo to try and eliminate the border, it can't be done, as it's part of the bitmap.

But, there's an adjustment in EzCad that may help, it lets you pick a gray value to 'ignore' when it engraves. Even with all white I guess it considers white somewhat gray? Anyway, in the value box start by changing the gray value to 10, which should not engrave gray values of 10 or below on the 255 shades scale... hope that makes sense!
bmpfx.jpg

[John Lifer]

If it were me, I'd pay the $20 or $30 to have this image vectorized. That would eliminate the border, and would allow you to do more with this.
There are numerous folks that will do this that are on FB and other platforms. PM me if you want a name or two.

[Glen Monaghan]

[...] no matter how I manipulate a photo to try and eliminate the border, it can't be done, as it's part of the bitmap.

You're just not trying right, Kev ;^) There are specialized software packages marketed specifically for removing backgrounds, and typically they have the enhanced ability to deal with details like frizzy hair and such, but "simple" things like the OP's image don't need anything more than Corel Paint (although PhotoShop makes it a lot easier with its Magic Wand and Quick Selection tools). And, for the OP's purpose of marking a pistol slide, you don't even have to be super picky about the border pixels because the end result will be so small... I just finished cutting several crows and sunflowers from pictures to composite for two different "Sunflower and Crow" themed mugs, and it took me about 3 minutes each on average.

[Kev Williams]

I know how to get transparent backgrounds -- but regardless of whether the background is transparent or not, every bitmap has a border; look at it in wireframe, you'll see there is still a 'bounding box'. In my experience, EzCad will not 'see' anything within the bounding box of a bitmap as transparent. Depending on how out of whack the settings are at any given time, EzCad will engrave a solid 'gray' box regardless of the image. Even my C02 lasers aren't immune-- I create all my bitmaps with 1-Touch, and sometimes the last thing that engraves, much to my chagrin, will be the top or bottom edge of a bitmap's bounding box, transparent background or not.

and as to vectorized photos, while you CAN get some nice engraving, you just can't capture the nuance of halftone engraving. At least, I can't!

[Kev Williams]

Ok--

Here is a vector flag in Corel, that I made 2 copies of, in 300dpi grayscale--
flag1.jpg
the first copy has a transparent background,
the second copy does not. Both copies are 'in front'...

Here I've overlaid the flags onto the original,
as you can see the top flag is transparent,
the bottom flag is not
flag2.jpg
--here are the wireframe views.
Both bitmaps have a bounding box,
the vectored flag does not...
flag3.jpg
--EzCad, in my experience, doesn't care about transparent backgrounds...

[Glen Monaghan]

Ah, okay, well that's an EzCad issue and I have no experience with that software, so I'll bow out...

[Darren Wilson]

Vectorize for the win