It is a different process than when you are working with screen printing to prepare artwork for direct-to–garment printing. Here are a few considerations when you’re working with images for DTG. These instructions were written for Adobe Photoshop shops, but many of these methods can also be used in other raster graphics programs such as Corel Photo Paint.

Learn your limitations. DTG machines print with the standard cyan (CMYK), magenta (Yellow), and black colors. When you convert a great-looking digital file from RGB to CMYK, many colors go “out of gamut,” meaning they can’t be reproduced exactly using just CMYK. DTG colors can be duller – especially spot colors – than a typical screen print. If the customer is used to seeing a bright scarlet screen print on a white shirt and you then do the same job with DTG, the red won’t be as vibrant. You have to make up for the loss by tweaking.

A DTG image will pop if the saturation is increased by 10-20 points.

Select the correct file type Although JPG files often have a white background and are common, you will need a PNG file that has a transparent background. Just as with screen printing, you can’t make a proper underbase when the file has white (or a shirt color) around the image. Learn how to remove backgrounds so there’s transparency around the image. Most raster image processor (RIP) software for DTG has features to “knock out” the background. There’s also a lot of inexpensive third-party software that can do this.

Adjust your image resolution. Low-resolution 72 DPI images are often very small in physical size. First, go to Image/Image Size. Next, upsample your image to 200-300 dpi to make it larger. This minor improvement will eliminate “jaggies” and smooth the edges.

Enhance low-quality JPG images If the image was a low-quality JPG file, you might see “artifacts” and “blocks.” Unlike screen printing where such imperfections might show up in the final print, these problem areas may not be as noticeable on a DTG image. To improve your JPG image or remove boxes and artifacts, you can use inexpensive JPG enhancement software.

Improve your color saturation. This is a huge deal. This is a big deal. Go to Image/Adjustments/Hue Saturation and move the Saturation slider up about 10 to 20 points. Don’t overdo it – just get the colors to pop a little.

To improve contrast, you can also use the Tone Curve. An S Curve is what I prefer to call it. This darkens shadows and highlights, and can make a big difference to a flat image. Go to Image/Adjustments/Curves.

Sharpen the image. Photoshop has a wonderful Sharpening filter which can improve/enhance the edges of an image if it is used correctly. Go to Filter/Sharpen/Unsharp Mask (don’t let the name fool you) and start with a setting of Radius 1.0, Threshold 6.0 and Amount 250. Move the Amount slider upward or downward. Preview must be checked in order to see the effect. But you should always go backwards and forwards to see any changes to the image.

Black and white areas should be fixed. Sometimes, what appears to be solid black on your monitor may not be so. Open the Info Panel (Window/Info) and stick it somewhere so you’ll never close it. I use this panel all the time – it reads density levels. The eyedropper tool is available in most panels. Place the tool on areas that are considered dead black. Dead black refers to RGB levels 0 and 1. Any reading other than 0 means you won’t have dead black in that area. The result will be a dark grey. You can do the same with white areas. The color of dead white is 255 levels in RGB. Your RIP will put a tiny amount of color in any other reading. You can adjust these areas with Tone Curve.

Scott Fresener is a veteran of the industry and co-author of How To Print Shirts For Fun And Profit. A popular speaker at trade shows, he runs the website www.T-BizNetwork.com. Reach him at [email protected].