Laser Photo Engraving By Kathryn Arnold --This article includes a link to watch the video version! Learn online courtesy of LaserUniversity! -- Society is now in the digital age and so too must the world of laser engraving. Human nature is to remember the good times and great people in our lives and photography has been the media for capturing family and friends in all kinds of settings. Our closets are filled with the memories of our childhood, school days, weddings and so many other important events in our lives. Customers frequently ask us the question of why they should purchase a new laser system. The answer is a simple one. Modern lasers are profitable because they are very flexible and can work with so many materials. Creating unique products for your customer is a path to success. A photo of a loved one laser engraved on a keepsake has tremendous value to your customer. Think of this old adage, if a picture is worth a thousand words, how much is a photo laser engraved on marble worth? Today, photography is easier than ever with digital cameras and desktop computers. Our digital snapshots can be sent via the Internet around the world in seconds using powerful computer technology. This same computer technology allows us to scan color or black & white photos or to take digital photos and then laser engrave these images on various materials such as marble, wood, leather, coated metals, acrylic and so much more. The process of laser engraving photos is easier than you think and can open many new business opportunities that you never have imagined. The Right Tools Having the right tools for the job always makes the task easier. Working with photographs can require moderate computing power to perform tasks quickly without a lot of waiting. Part of the issue with slow processing times is with the software used to edit digital photographs. Image editing programs like Adobe Photoshop or Corel PhotoPaint take considerable computer resources to operate and can take their toll on a computer s performance. Two rules of thumb apply to speeding up a computer editing images: the first is having enough memory available. Editing programs need plenty of Random Access Memory (RAM) for faster display updates and image data storage. Most new computer systems come with 512 of RAM which is adequate. Adding more RAM memory is an easy upgrade to older systems with an immediate performance increase. The second rule for fast processing of images is that there is nothing better that pure horsepower in the form of a fast processor chip. Providing your system has plenty of memory, a 2.2 Ghz computer system is capable of timely computing processing while a 2.5 GHz (or faster) system will have no problem with the largest of file sizes. The next key component is the scanner, which will be a large factor in determining the final image quality. A major brand name flat bed scanner with a 600 x 1200 resolution will be capable of just about anything you will ever need to reproduce. Having USB capability is an excellent feature for a scanner, making it both easy to install and operate. The following instructions cover the basics for preparing your images for laser engraving. You will find much of your success for laser engraving photos comes in the preparation of the job. Keep it simple in the beginning and work into more advanced techniques over time. Software: PhotoGrav Since necessity is the mother of invention, a new process for laser engraving photos was developed several years ago to improve the productivity of the traditional method of processing. The idea was to create a software product that removed all of the variables in the process and was simple to operate. The result is a product called PhotoGrav, which is designed by laser engravers for laser engravers. Before, the laser operator needed to adjust for traits of the scanned photo as well as the material to be engraved. This required testing and resulted in a lot of used time and materials.
PhotoGrav is an excellent photo engraving software specifically designed for laser engraving photographs. This software is for image processing the scanned bitmap photograph and optimizing it for laser engraving onto standard engraving materials. After processing the image with PhotoGrav, the photo can be imported in standard page layout or engraving software for printing to the laser engraving system. The PhotoGrav software has predetermined response curves for over 30 accepted engraving materials and special algorithms to process the scanned photo image to create an excellent first run engraving. The software also produces a "simulated image" after processing to give you an idea of what the image will be when it is engraved. The PhotoGrav software comes with an excellent manual that shows step-by-step how to create good results. Tech support is both prompt and accurate. This type of software works well in production environments where you need to engrave several different photos. The Variables of Laser Engraving Photos The laser engraving system works very similar to a regular black and white printer, so preparing a photo for engraving is almost identical. However, several variables exist in the process of laser engraving photos. To achieve the best results, consider all of these variables and try to reduce their impact on your engraving work. 1) Start by considering the original photo you are scanning. The best photos to scan have detail in the dark areas (shadow) and in the light areas (highlight). Since all of the photos are scanned as a black & white image, it does not matter if the original photo is color or black & white. Typically, you will not find many photos supplied by customers that feature good tonal range and some compensation will need to be considered. 2) Consider the resolution settings and lens on your laser system. For best results set the DPI resolution settings in the print driver to a mid-range of 500 or 600. Engraving photos at any resolution setting below 500 or 600 DPI will result in too many jagged pixels and the engraving will not have smooth graduations between dark and light areas. Be sure to use a focus lens that has a focal length of 1.5 or 2 inches. These lenses will generate a small laser spot size needed for clear, defined engraving. 3) Selecting the material to engrave on may also have an effect on the quality of engraving. The most dramatic results for a photo use a material that will have excellent contrast when the laser engraves. Some materials that work well for this application are acrylic, marble, wood, leather, coated metals and anodized aluminum. All of these materials react differently to the laser and some compensation to the scanned photo may be necessary to achieve best results. The Process of Laser Engraving Photos 1) Start with scanning the photo between 250-300 DPI as a black & white photograph. Scanning the photo can be done using the Acquire function in DRAW and Corel PhotoPaint (File>AcquireImage>Acquire) or by using the stand-alone scanning program that comes with the scanner. The scans are automatically saved in a Temp folder. 2) After scanning, open the photo in photo editing software such as Corel PhotoPaint. (Here are the steps: Open CorelDRAW, go to File>Import and navigate to the location of the image to open it in DRAW, and then with the image selected, go to the menu Bitmaps>Edit Bitmap to proceed to Corel PhotoPaint.)
3) Crop the photo. Use the Crop tool. Click and drag the crop tool in position over the photo. Let go and handles will appear. Keep adjusting the positioning of the crop until satisfied, then hit Enter on your keyboard to apply the crop 4) Now that the photo has been cropped, it needs to be resized to match the dimensions of the areas where it will be engraved. A quick method to scale the photo to the correct size is to use the Resample tool. (Image>Resample) After selecting Resample, enter the finished engraving size needed and the program will adjust the size. Also, adjust to 300 dpi. Click OK when ready. This may take a minute or so to process. Note: If you are using an image from you a source other than scanning (i.e. from your computer or digital camera) you will need to import that image into PhotoPaint and complete steps 3 & 4 for final engraving size and DPI. 5) Optional step: Adding a vignette look to the image will add a professional looking flair to the finished engraving. Select the Ellipse Mask Tool and draw an oval around the subject. To do this, click the tiny black tab in the lower right of the Rectangle Mask tool and a submenu will fly out to the right. Select the Ellipse Mask tool from this submenu. Draw a circle or oval on the photo to capture the portion you wish to engrave. Didn't quite get the correct placement? Do a Ctrl-Z to "undo" and try again. When ready go to Mask>Invert to invert the selection. Then go to Mask>Mask Outline>Feather. Adjust the Feather feature to 20 for a nice blended edge effect. Click OK. Hit Delete on your keyboard to delete the extra photo portion and to see your feathered effect. Go to Mask>Remove to stop the mask feature. 6) Now convert your image to an 8-bit grayscale bitmap (PhotoGrav will only accept photos at this setting). Still in PhotoPaint, go to Image>ColorMode>Grayscale (8-bit) or Image>Convert Grayscale (8-bit) depending on your version of Corel. 7) Now save the modified image area in a folder.
8) Launch PhotoGrav and make the initial selections of the brand and wattage of your laser. Click OK. 9) Open the scanned 8-bit grayscale bitmap in PhotoGrav by clicking on the Open Image button. 10) Click Select Material to select the appropriate material from the list of 20 different materials. Click OK. 11) Click on the Auto Process button and watch the magic happen. Your computer is now adjusting for all the variables in the photo, the laser system and the material to be engraved on. After a short processing time you can save the processed image in a folder. 12) Finally, import the processed image into CorelDRAW and you are ready for engraving. If you chose a material in PhotoGrav for reverse side engraving, the processed image includes all of the modifications needed. This is a great feature as I usually forget this step when I use the traditional method and have to engrave a second piece to fix the blunder. 13) The final step is to adjust the power and speed settings. Use the normal power and speed settings as if you were engraving text or other graphics on the specific material. Load the material to be engraved into the laser system and check for correct focus. Scanned & Cropped Image PhotoGrav Processed Image on Silver AlumaMark Based on the results from customers around the world using this product, we can safely say that almost every job processed using PhotoGrav will give great first run results. What really makes this program so effective are the processing modules that calculate far past the capability of any laser system print driver. These detailed modules have advanced processing for generating highly accurate diffusion dithering and halftone patterns, gray shade mapping for highlight and shadow detail enhancement, and even a simulation mode to see the enhanced image before engraving. These and many other features operate automatically when the Auto Process button is clicked. Each module has adjustable features for detailed tweaking of the features for top performance if the operator would like to. A great percentage of the time the engraving quality will be excellent. In case the quality of engraving needs improving, try modifying the tonal range of the scanned image. Usually the most difficult photos to engrave have low shadow and highlight detail. The laser engraving process adds contrast to the photo and results in blocked in areas that do not look like a photograph. Your editing program (Corel PhotoPaint) has a tool called Tone Curve (Image>Adjust>Tone Curve) that can adjust the shadow and highlight areas for improved engraving quality. After adjusting the Tone Curve of the photo, engrave it again and compare the results.
Many customers use PhotoGrav software in a production environment successfully by standardizing the photo engraving process. For example, scan all photos needed at once then process in image editing software and then in PhotoGrav instead of doing one photo at a time. As with every new process learned, there can be a learning curve. After your first few images are scanned, edited and PhotoGrav ed, you will get the hang of photo engraving. This will open a whole new world for both you and your customers. Watching a video can be very helpful when learning a new process. Please go to http://www.laseru.com/laseru/1234/photo.html you can watch the video version of photo engraving with PhotoGrav. The video will take you through the steps of scanning the photo, processing in image editing software and then processing with PhotoGrav. This has been provided Courtesy of LaserUniversity.