Getting started with laser engraving
Answered on this page:
- How should I prepare images for laser engraving?
- How can I make sure that my image engraves well on stainless steel?
- What software should I use to prepare a photo/image for laser engraving?
- How can I get the best quality laser engraving with a photo?
If you’ve never worked with a laser engraving machine before, you might be surprised at what’s possible when you finally get into a workshop and start the process for yourself. Laser engraving is a diverse application – it can be used to mark medical devices or aftermarket automobile parts that will withstand the toughest conditions, or to commemorate a birthday or special event by marking the date on a keepsake item.
One of the coolest applications we’ve seen for laser engravers involves working with real life-like photographs and images. Our galvanometer laser systems are so precise that, beyond engraving words and phrases, you’ll actually be able to engrave photo-realistic images into stainless steel. You’ll have to be happy with grayscale, but this incredible process produces great results when you set up the image correctly.
Based on our own process of trial and error, we’ve come up with the ideal step-by-step process for preparing your chosen image for laser engraving. With so many different types of laser engravers available, and many software options for preparing images, it’s difficult to generalize a method that’s consistently applicable, but we’ve done our best to make this guide accessible for everyone. Whether you’re an experienced designer working in Corel DRAW, or you’re using the free online tool GIMP, follow these steps to get your image ready for engraving.
Step One – Start with a High-Quality Image
When choosing an image to laser engrave, it’s important to start off with a high-resolution, high-quality image. A postage-stamp picture that you scanned out of an old photo album will not maintain its clarity through the transformations that need to happen before the image is ready to engrave, and you won’t be able to “inflate” or “blow-up” the picture like in the CSI television show. Make sure you take a high-resolution picture with a good camera to get the best results.
Step Two – Crop to Perfection
The advantage of starting with a high-quality photo is that you’ll be able to crop it effectively with making it look awful. Cut out the parts of the image that you don’t need and resize what’s left to the dimensions that you want it to appear on the stainless steel or other material you’re using.
Step Three – Remove the Background
This step is important and may require use of the cutting tool in your image processing software, or some handy Photoshop skills. If you don’t remove the background, your image could get lost in the background during the engraving process. By making the background of the image plain white, the laser machine only engraves the focal object and you avoid obscuring the object with irrelevant background details that you don’t want.
Step Four – Convert the Image to Grayscale
Laser engraving produces grayscale images naturally by cutting different lines at different depths for different numbers of passes. Producing your image in grayscale gives you a good idea of what it will look like once it’s been engraved onto the material of choice – your image is almost ready! Looking at the image in grayscale should help you with the next steps, where you’ll have to do some light editing to the image for optimal results.
Step Five – Edit Your Photo However You Choose
Now that we’re looking at something similar to what the laser engraver will produce, we can start making any editions that are important for achieving the desired outcome. Editing photos is a highly subjective process, but we’ll provide a few pointers. These can be applied to photos of people, places, or objects.
- You want to try and maximize the contrast in key areas of the photo. This typically means making the whites whiter and the dark areas darker.
- Areas that appear white in real life, like the eyes or fingernails, 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 on any faces in the image because the darkness contrasts too heavily with hair, which is usually much darker. Set the Black to 10-15% for optimal results.
- For dark hair strands, darken them even more. For light hair strands, you can make them a bit lighter.
Step Five Alternative – Color Indexing
If you’re not about to get into editing your photo, there’s an option you can choose to help maximize the contrast without having to do any complex changes on your own – that tool is color indexing. If you plan to use color indexing, you may want to do it before you change the image to grayscale.
Color indexing is a tool that some imaging software has which can re-draw your photo with a fixed number of colors for maximum contrast. It essentially looks at all of the colors in the image, groups them together into as many groups as you choose, and replaces each group of colors with a single color. All you need to do is choose how many colors you want for the image and let your image processor do the rest.
Step Six – Sharpen Your Image
Sharpening just makes lines look bolder, and it’s a simple tool that’s present in virtually all photo editing programs. For photographs of people, sharpen areas like the eyelashes, lips, hair around the face, and anywhere else that you would like to emphasize in the final engraved image. If you’ve photographed an object or a building, focus on the most important lines that add texture to the image and make it feel three dimensional.
Step Seven – Convert and Export
Now your image should look just the way you want it engraved on your stainless steel, plywood, or other material. The next step is to convert that image to a bitmap of appropriate resolution and end it to the laser CAD software so it can be engraved. When exporting to bitmap, a recommended resolution is around 200 pixels per centimeter. This ensures that your image will appear in high resolution on the material you’ve chosen.
Step Eight – Push the Red Button
The last and most fun step is always setting up the options on the laser cutter and finally pressing “go” after you’ve done all the hard work. Engraving is different from laser etching in that it makes deeper cuts in the material, and it’s usually better to program the laser for multiple passes over the material, rather than trying to blast out big chunks of steel or wood in a single pass. Our galvanometer lasers use a system of oscillating mirrors to make cuts at extremely high speeds, so your project will be done in just minutes.
Conclusion
You’ll be amazed at the quality of images that you can reproduce on a piece of stainless steel, birch wood, or laminate just by following these simple steps. You don’t have to be a graphics wizard either – in fact, it doesn’t really matter what program you use, as long as it can perform the basic functions we outlined above. Whatever you choose, remember that the most important point is to start off with a clear, high-resolution image. A great picture is a great starting point for producing something fantastic with our laser engraving machines.
