If you ever produced a ChromaLuxe panel, than you know that it will show every detail and color of your beautiful image … also when your image is not 100% sharp. It all starts with a sharp image, and sometimes that’s not the case (because you didn’t shoot the image yourself for example). That’s one of the reasons why they did invent the application Photoshop back in 1988. In the latest versions of Photoshop, you have the filer called “Unsharp Mask”. The Unsharp Mask filter in Photoshop works by increasing the contrast of your image and I will explain below how to use it in a proper way:
How to sharpen photos with the Unsharp Mask filter
STEP 1 : Crop and resize
Open your image in Photoshop. Use the Crop tool to crop the image as desired. Choose Image > Image Size, enable the Constrain Proportions and Resample Image check boxes and set your desired resolution and size. We set Resolution to 300 Pixels/Inch and Width to 16 Centimeters. Click OK.
STEP 2 : Launch the filter
To sharpen the image, choose Filter > Sharpen > Unsharp Mask. Click a portion of the image that contains detail such as the centre of the flower. This then appears in the filter dialog box sized at 100%.
STEP 3 : Set the Amount
Set the Amount to 150%. The Amount controls how much sharpening is applied to the image. You can readjust this later, but for now, you want to see the results of adjusting the other sliders clearly.
STEP 4 : Radius tweaks
The Radius sets the width of the haloes around the image edges. The larger the Radius, the wider the haloes are. For a sharp image, set the Radius to something between 0.5-1.5. We used a setting of 1.0 here.
STEP 5 : Adjust the threshold
The Threshold setting controls how much difference in brightness there must be between adjacent pixels for them to be considered an edge. A small Threshold value sharpens everything and a large one sharpens nothing. We set the Threshold to 10.
STEP 6 : Fine-tune the result
Readjust the Amount to fine-tune the result. When sharpening for your output on a ChromaLuxe panel, adjust the Amount based on what you see on your (calibrated) screen. Do not over-sharpen, because on the ChromaLuxe panel, you will see the over-sharpen effect very easily. Click OK to apply and save your sharpen image.
Now your image is ready to print on the ChromaLuxe panel. Add your image in the RIP software to print it on a professional large format sublimation printer and enjoy the sharpness and details, after pressing it on a heat press, on the size you want.
Steven Roesbeke has a huge experience in the graphical industry with a lot of expertise in color management and output solutions. Since 2013 he is the Technical Support Field Engineer at Universal Woods EMEA. Read his technical blog posts to discover helpful tips & tricks and learn more about the do’s and dont’s of (large format) sublimation. You can always contact him at firstname.lastname@example.org