There are a number of key features that every printer has that contribute to the quality and productivity of that printer. The main ones include resolution, number of passes, carriage speed, printhead size and print modes. Dot size is also important but most printers don’t allow for selecting drop size, so we won’t discuss that here.
- Resolution—Print resolution is based on a the number of individual dots of ink that appear within a square inch of full coverage print—dots per square inch (dpi). It is measured both horizontally and vertically, for example 1440 x 720 dpi. Sometimes the first figure is larger than the second. That’s because since the printheads are perfectly aligned along the printhead carriage, and they print more efficiently and accurately shuttling left and right versus up and down as the media advances.
- Number of Passes—Passes refers to how many times the printheads have to pass over the image to achieve the full resolution. On most printers, each pass will put down a series of lines of ink, and as these lines are passed over one another, they produce a perfect image. The more the passes made by the printheads the better the print quality—and the slower the print speed. The trick is to run as few passes as possible without sacrificing print quality.
- Carriage Speed—Carriage speed refers to the speed that the printheads travel back and forth along the print carriage. Most printers allow you to run the carriage faster for lower resolution print jobs. To maximize speed, run the carriage as fast as you can without sacrificing needed print quality. In most cases you can control the carriage speed from within the RIP.
- Printhead Size—It makes sense that the size of the printhead makes a huge difference on speed because, wider printheads have more inkjet nozzles delivering more ink across a wider area resulting in a wider band for each print pass.
- Print Modes—Depending on the RIP you are using, you should be able to set up the modes you need to run your printer at the best speed. I use two modes. I generally run in production mode (720 x 720) as this mode is just about perfect for most jobs. I may set up a fast mode (360 x 540) for jobs where the resolution of the file is not high, or the job is for longer viewing distance (fleet wraps) or if time does not allow for a higher resolution mode.