Optimize Print Quality
Thermal printers work by printing small dots. Printers can print anywhere from 200 DPI (dots per inch) up to 600 DPI. A larger number means higher perceived quality. The two most common DPIs are 200 (popular entry-level Zebra printers such as GK420d, GX420t) and 300 (entry-level consumer models like DYMO LabelWriter 450 and Brother QL series such as QL-700, 800, etc).
Printer manufacturers have settled on these two DPIs because they are generally "good enough" for the labels most people need.
At 200 DPI, most text and barcodes look good at a distance, but small text at 200 DPI can start to suffer in quality.
Increasing to 300 DPI helps with printing and reading small text, but there are tradeoffs. Higher DPI printers are generally more expensive and slightly slower.
For this example, let's assume a 200 DPI thermal printer that prints one color (black) on white label stock.
Pixel Alignment and Dithering
Your computer's screen has many more dots than the printer... so Label LIVE has to tell the printer exactly where to place the black dots. It does this using a technique called dithering. Label LIVE has built-in dithering for images. We recommend trying at least two: Threshold and Floyd-Steinberg. Test both and choose the one that works best for your label.
Here's a quick fake logo I created to illustrate the differences in dithering.
Here's what the logo looks like after importing into Label LIVE using a technique called Floyd-Steinberg.
Not great for our logo. The green has turned into a shade of black dots. If you zoom into the COMPANY letters, you'll notice misplaced dots.
This "M" looks especially ugly.
Optimizing Text or One-Color Images
This logo has text and a few colors, so it's a great candidate for Threshold dithering. Just click the dithering menu and select Threshold.
This "M" looks especially good!
Why would we want to use Floyd-Steinberg? Photos!
Let's look at printing a "simple" black and white photo.
Technically, the photo is grayscale... but label printers can't print gray dots, only black. Let's see how Label LIVE handles dithering for this image.
Here's what the photo looks like after importing into Label LIVE.
Not bad! (if I don't say so myself)... 😂
Ruining The Photo
If we go back and try to apply Threshold dithering to this photo the results are poor.
Whenever you import an image try switching between the first two dithering options.
Threshold - Use for text and one-color images
Floyd-Steinberg - Use for images and complex shading, brightness, or curves
In this post you saw how different images can be optimized for printing to a black and white thermal printer. Here are some more ideas to further optimize your images:
If you have both text and photos in the same image, consider breaking it into two separate image objects
If you use a lot of text in an image, consider cropping out the text and adding it as separate text objects
Scale your images to the approximate size before importing. If you want your logo to be 1" square on a 200 DPI printer, the image should be about 200x200 pixels in size.
Save your images as PNG with as few colors as possible
Artificially edit out backgrounds, shadows
Avoid the use of thin and curved lines
Don't accidentally rotate your object in Label LIVE - use the CTRL or CMD key to "lock-in" a fixed rotation
Label LIVE is a great tool for generating and printing high-quality images. This example only uses a single image, but with Label LIVE, you can include text, barcodes, shapes, and excel spreadsheet functionality. These features are just a few clicks away.