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I developed this easy way to enhance your high contrast images, laser-engraved onto the back of clear acrylic plastic sheet at Makerplace in San Diego, CA using their 100 watt Hurricane laser. You can engrave any kind of image. For this demonstration I'll use a portrait. What sets this technique apart is the use of black and white paint on the backside of the acrylic sheet to dramatically intensify your high contrast images.

Here's what you'll need:
• Your image
• Adobe's Photoshop or other image authoring tool
• Access to a Laser cutter
• Flat black and white paint (I use spray paint for the black as it coats evenly and for the white, Liquitex's heavy body acrylic titanium)
• A sheet of acrylic

Prepare the Image File
I use Photoshop CS4 as my image authoring tool. You'll want to do the equivalent in whatever tool you use.

Step 1: Turn Your Color Image Into Grayscale

• Image > Mode > Grayscale

Step 2: Turn Your Grayscale Image Into a Bitmap

• Image > Mode > Bitmap (Output:60; Method: Diffusion Dither)

Step 3: Invert Your Bitmap Image

• Image > Adjustment > Invert

Step 4: Flip Your Inverted Image

• Image > Image Rotation > Flip Canvas Horizontal

SAVE AS Bitmap file (.bmp)

Step 5: Prepping the Substrate

• Peel the protective film off of one side of your acrylic sheet. Leave the protective layer on the other side for now.
• Spray the acrylic with an even coat of flat black paint. Let it dry
• Spray the acrylic with a second even coat of flat black paint and let it dry.

Step 6: Settings to Engrave the Image

• Place the painted acrylic sheet paint side up on the bed of your laser cutter.
• Focus the laser for the thickness of this material.
• Import your bitmap .bmp file
• Engraving on acrylic works best when the process is done at high speed and low power.  On the 100 watt laser at Makerplace, my settings were Speed: 900, Power: 55 and the Span Gap at .085

Step 7: Engraving the Image

• When the laser is done, remove the acrylic sheet from the machine and clean it with a soft paper towel to remove any residue created by the engraving.

Step 8: White Fill the Engraving

• Place your acrylic sheet engraved side up on your work surface
• Paint the acrylic with an even coat of white paint (I'm using acrylic titanium white)
• Let it dry

Step 9: White Fill -- Second Coat

• Paint the acrylic with a second even coat of white paint.
• Let it dry

Step 10: Voila!

It's that easy. Cut to size, peel the protective film off the front side and your stunning high contrast image is ready for framing.

Thank you Makerplace for providing the space, tools and support in developing this novel idea.
<p>I'm trying to come up with a cheap way of lasering acrylic leaves. Do you think I could use bronze, silver, and gold spray paint to achieve similar results? I realize I might need to do a coat of matallic paint, then a coat of black so as not to interfere with the laser and reflection during the engraving process but I wanted to run that by someone who has actually worked with painting acrylics before lasering before trying it myself. </p>
<p>As the paint is applied AFTER the lasering, the reflectivity is not an issue. All acrylic and oil based paints, aerosol or brushed on have adhered nicely to acrylic sheet.</p>
<p>I used this method you suggested regarding grayscale/dithering on a scrap of leather (for a test). Turned out great. Thanks for sharing your ideas.</p>
<p>Nice,<a href="https://www.instructables.com/member/ETERNUR" rel="nofollow">ETERNUR</a>!</p>
<p>Welcome!</p>
<p>Clear acrylic sheet right? Was thinking of trying this on a diffused white sheet as well.</p>
<p>Hmmm,<a href="https://www.instructables.com/member/gharris14" rel="nofollow"> gharris14</a> -- not sure you'll be able to get as much definition with white acrylic, as the the fill color (white in my example) is seen through the surface of the clear plastic sheet. However, it's worth a shot just to see what the effect is. Let's us know what you come up with ... good, bad or ugly<a href="https://www.instructables.com/member/gharris14" rel="nofollow">.<br></a></p>
<p>You should also mess with the brightness and contrast. I usually bump both up to 25. I also use an unsharp mask with the amount at 500%,the radius between one and five,and the threshold at zero. You can toy around with these setting,but this will pretty much guarantee that your picture will be more photolike and less grainy.</p>
<p>Yes, of course, contrast your image to taste. Good point, <a href="https://www.instructables.com/member/Th3rdsun" rel="nofollow">Th3rdsun.</a></p>
<p>After the second coat of white paint did you wipe it off? It seems there is a missing step here.</p>
<p>&bull; Paint the acrylic with a second even coat of white paint.<br><br>&bull; Let it dry<br> </p>Step 10: Voila! &gt;&gt; you're done.
<p>so whats the next step after 2x white paint?</p>
<p>&bull; Paint the acrylic with a second even coat of white paint.<br><br>&bull; Let it dry<br> </p>Step 10: Voila! &gt;&gt; you're done.
<p><li> <br> <br>&bull;Paint the acrylic with a second even coat of white paint.<br> <br>&bull; Let it dry</p><p>That's it. Finished. Painting the back of the engraving is the last step.</p>
<p>&bull; Paint the acrylic with a second even coat of white paint.<br><br>&bull; Let it dry<br> </p>Step 10: Voila! &gt;&gt; you're done.
I see that you are also a fan of George Carlin!
very very cool!

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Bio: Artist and designer, making novel ideas tangible.
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