Laser engraving is a versatile application - it can be used to mark medical equipment or aftermarket auto parts that can withstand the harshest conditions, or to commemorate a birthday or special event by marking the date on a souvenir.
One of the coolest applications for atomstack laser engravers we've seen is working with photorealistic photos and images. Our galvo laser systems are so precise that in addition to engraving words and phrases, you can actually engrave photorealistic images into stainless steel. You have to be comfortable with grayscale, but when you get your images set up correctly, this incredible process produces great results.
Based on our own trial and error process, we have come up with the ideal step-by-step process for preparing your chosen laser engraving image. With so many different types of laser engravers available, and so many software options for preparing images, it's hard to generalize about a one-size-fits-all approach, but we've done our best to make this guide accessible to everyone. Whether you're an experienced designer working with Corel DRAW or the free online tool GIMP, follow these steps to prepare your images for sculpting.
Step 1 - Start with a high-quality image
When choosing an image for laser engraving, it is important to start with a high-resolution, high-quality image. A stamp image scanned from an old photo album will not retain its sharpness through the transformation that occurs before the image is ready for engraving, and you will not be able to "inflate" or "zoom in" like a picture from a CSI TV show. Make sure to use it well camera to take high-resolution photos for the best results.
Step 2 - Cut to Perfection
The advantage of starting with a high-quality photo is that you can effectively crop it and make it look bad. Cut out the parts of the image that you don't want, and resize the rest to the size you want it to appear on the stainless steel or other material you're using.
Step 3 - Remove the Background
This step is important and may require using the clipping tool in your image processing software or some handy Photoshop skills. If you don't remove the background, your image may get lost in the background during the engraving process. By making the background of the image pure white and the laser engraving only the object in focus, you can avoid obscuring objects with irrelevant background details you don't want.
Step 4 - Convert the Image to Grayscale
Laser engraving naturally produces grayscale images by cutting different lines at different depths for different number of passes. Generating an image in grayscale gives you a good idea of what it will look like when sculpted onto the material of your choice - your image is almost ready! Looking at the grayscale image should help you with the next steps, you'll have to make some slight edits to the image for best results.
Step 5 - Edit your photo however you choose
Now that we're working on something similar to what a laser engraver will produce, we can start making any version that's important to achieve the desired result. Editing photos is a highly subjective process, but we'll offer some advice. These can be applied to photos of people, places or objects.
You want to try to maximize contrast in key areas of your photo. This usually means making whites whiter and dark areas darker.
Areas that appear white in real life, such as eyes or nails, should be highlighted in the image by reducing any shadows that appear there. Set the black to 3-6% to help these areas stand out better.
Remove shadows from any faces in the image, as the dark contrasts too strongly with hair, which is usually darker. Set black to 10-15% for best results.
For dark tresses, darken them. For lighter tresses, you can make them lighter.
Step 5 Alternative - Color Index
If you're not going to edit your photos, there's an option you can choose to help maximize contrast without having to make any complicated changes yourself - that tool is Color Index. If you plan to use color indexing, you may need to do this before changing the image to grayscale.
A color index is a tool that some imaging software has that repaints your photo with a fixed number of colors for maximum contrast. It essentially looks at all the colors in the image, combines them into any number of groups of your choice, and replaces each group with one color. All you need to do is choose the number of colors you want for the image and let the image processor do the rest.
Step 6 - Sharpen Your Image
Sharpening just makes lines look thicker, and it's a simple tool that exists in almost every photo editing program. For photos of people, sharpen the eyelashes, lips, hair around the face, and any other areas you want to emphasize in the final sculpted image. If you photographed objects or buildings, focus on the most important lines that add texture to the image and give it a three-dimensional feel.
Step 7 - Convert and Export
Your image should now look the way you want it to be sculpted on stainless steel, plywood, or other materials. The next step is to convert this image to a bitmap of the appropriate resolution and transfer it to laser CAD software for engraving. When exporting as a bitmap, the recommended resolution is approximately 200 pixels per centimeter. This ensures that your images are displayed in high resolution on the material of your choice.
Step 8 - Press the red button
The last and most fun step is always setting the options on the laser cutter and pressing "start" at the end after all the hard work is done. Engraving differs from laser etching in that it makes deeper cuts in the material, and it's usually better to program the laser to make multiple passes over the material, rather than trying to blast a large piece of steel or wood in a single pass. Our galvo lasers use an oscillating mirror system to cut at extremely high speeds, so your project will be complete in minutes.
Just follow these simple steps and you can reproduce images of stunning quality on a piece of stainless steel, birch or laminate. You also don't have to be a graphical wizard -- in fact, it doesn't matter what program you use, as long as it performs the basic functions we've outlined above. Whatever you choose, the most important thing to remember is to start with a clear, high-resolution image. A great picture is a great starting point for creating great creations with our laser engravers.