It’s time to get your artwork print-ready. The best way to do that is to create a transparent PNG of your image. This means that we need to knock out the background of an image so that 1) you can use one design across an array of colors and 2) only your design prints on the canvas and not a big box surrounding it.
FROM A SCANNED IMAGE: SIMPLE DRAWINGS
*It’s important that you scan in your artwork at 300dpi for highest quality. In the example below, you’ll see that sometimes a scanner can wash out your linework and give a faded tint to the paper. For best results, adjust the Levels (Image > Adjustments > Levels in Photoshop) to bring out more black in your lineart and also white in the paper.*
There are a few ways to do this, depending on the nature of the artwork. For simple and clean artwork, you can simply important this image into Adobe Illustrator and do an Image Trace (Object > Image Trace). This will work really well for thick, clean and bold lines but not so much for heavily detailed illustrations.
So, using the same design as example, bring it into Illustrator and do an Image Trace. Here’s two important steps to do after:
After doing an Image Trace, it is essential to check the ‘IGNORE WHITE’ box in the Image Trace Window (will be under the ‘Advanced’ section)
After this, you should see the white background disappear from your design. Once you are satisfied with how this looks, expand the object to finish. (Object > Expand). Now that it’s expanded, you will be able to manipulate the color of the object if needed.
FROM A SCANNED IMAGE: ILLUSTRATIONS
Let’s say you have more intricate artwork such as pen or pencil line drawings. If you image traced this in Illustrator, it wouldn’t be able to pick up all the details you want – it would simplify it too much. There’s several ways to do this in Photoshop, but here’s a method I’ve found the most success with. It’s also the least time consuming with the best results.
Similar to the above, adjust your drawing’s Levels in Photoshop (Image > Levels) and get it to your liking.
Next, go to the Channels window and right click the Blue Channel and press ‘Duplicate Channel’. A ‘Blue Copy’ Channel should appear. Turn on this channel (eye to the left) and turn off every other channel.
Next, make sure your selection is this new copy, and invert the layer. (Image Adjusments > Invert or ⌘+I on Macs). You’ll see the layer become inverted. In Photoshop go to Select > Load Selection and press OK. You’ll see marching ants surrounding your illustration.
Go back to the layer window, create a new layer and simply fill with any color with the paint bucket. You should see your illustration as a separate layer from its background. Voila! You have your transparent art image now. Make sure you save as a PNG to preserve the transparency!
Now you can simply do a color overlay to adjust the colors of the lineart!
FROM A SCANNED IMAGE: COLORED ART / WATERCOLORS
Separating the background out of colored illustration – particularly watercolors is quite difficult. You will never get a perfect extraction, so the goal is to draw out as much color as possible. There are many ways to do this (i.e. Select > Color Range > Pulling out the white) but I’ve found this to be the cleanest/most successful.
This process is super similar to that of making transparent PNGs from very detailed illustrations as seen above, with a different step at the end.
So once, again, adjust your levels (Image > Adjustments > Levels) so that the background gets as close to white as possible, as well as your colors being nice and saturated. This is also a method you can use to remove some of the paper texture that the scanner picks up.
Once again, go into the Channels window and duplicate your Blue channel (Right click – Duplicate). Turn off every other layer and select the Blue copy layer. From the top menu, got to Select > Load selection. You should see some marching ants appear. (You’ll need to invert this layer if your background is black)
Go back into the layers menu and click on your drawing. Simply press the delete button and you should see the background erase from your design. You will however notice that by pulling out the background you lost some saturation/volume in the design.
The easiest solution to this is to duplicate your layers 2-3 times. You’ll notice your design saturate itself back to life. You can also tweak some of the layer styles to resaturate the colors a bit more. Don’t do any more than 3 times as you have the potential to add extra noise you don’t want. Pro-tip: create a background layer below the layers either in white or your desired t-shirt color to check your transparencies. And that’s it! You’ve got your transparent art file – make sure to save it as a PNG to preserve transparency.
My best suggestion, especially for watercolors is to keep them on lighter canvas colors (i.e. white). White is a great choice because no underbase is needed. When you get into super complicated watercolor art files, you have a chance of the underbase showing through on darker garments. Also important to note, when pulling out the white from colored illustrations, you might pull out white from areas you intended to be white – so always double check your work and make sure you add that back!
Your art work is transparent and ready to be set up for all the canvases. Make sure your final file is set up correctly to be uploaded!
For any other questions, or if you still need help, feel free to reach out to us at firstname.lastname@example.org.