Most people who use their printer to occasionally print photos or an email or two are not really concerned with resolution. Even if you have a really basic printer, the resolution will be sufficiently high for most printouts to look high quality, and the same goes for the most basic photo printers, which are capable of delivering great quality images.
However, if you’re doing a specific kind of work that requires the highest levels of detail, then you need to be well informed about resolution.
Video Explainer
Matt Granger explains, How big can you print? What DPI do you need? Interpolation? A quick run-through of what is involved, and clarifying a few misconceptions.
Dots Per Inch (DPI)
Printers work by printing tiny dots of either toner or ink onto the surface of the paper. Inkjet printers have nozzles that spray little droplets of ink, and laser printers burn small dots of toner onto the paper. The greater the number of drops or dots that you can fit into one square inch, the clearer the resulting picture will be. A printer with 600 DPI can place 600 horizontal dots and 600 vertical dots per square inch of paper. There are inkjet printers that have a greater capability in one direction, so it’s possible to see something like 600 by 1200 as a DPI for a printer. To a certain degree, if the resolution is higher, the image on the paper will look sharper.
Optimized DPI
Printers are able to put out dots of varying size, intensity and shape, and this can alter the look of the end result. Certain printers can even do a process called “optimized DPI” which means that the printheads are capable of optimizing ink drop placement to maximize print quality. This happens when the paper goes through the printer at a slower speed than it normally would. The result is that the dots actually overlap a little. The finished product is rich, but this technique of optimization takes longer and uses more ink than with regular settings.
Richer is not always better. For most regular people, choosing the maximum resolution for every print will simply waste resources. A lot of printers have a draft-quality setting. With this setting, the job prints out quickly and uses less ink. The result is not perfect, but it’s absolutely sufficient for regular everyday needs.
What DPI Is Adequate?
For letters and other business documents which include graphic elements, 600 DPI will be completely sufficient. If you need some kind of handout presentation for your board of directors, 1200 DPI will be optimal. This level is also perfect for most photographers. Both of these DPI levels are available with most printers that are on the market today. When you go higher than 1200 DPI, you will struggle to notice any difference in your printouts.
As always, there are exceptions to the rule. Professional-level photographers will need higher resolutions, some of which will go as high as 2880 by 1440 DPI or even more.
Ink Type Can Make All The Difference
DPI is not the only component of resolution. The type of ink you choose to use can even have a much bigger effect than the DPI. Text looks much sharper on a laser printer because toner doesn’t bleed like regular ink does. If your main goal is black-and-white printing of documents, then you should choose a laser monochrome printer to get much crisper text than an inkjet ever could, even with high resolution.
Paper Choice is Important
Paper is made in specific types according to the printing being done, and so the proper choice can result in excellent images whatever the DPI used by your printer. Normal copy paper is great for laser printing because there is no absorption. By contrast, inkjet ink is water-based and gets absorbed by the fiber of the paper. For this reason, there are special paper types used for inkjet and this is also the reason that a photo printed on normal paper looks so bad. If you just want to print an email or a letter, you can use normal copy paper, but if you want to produce some kind of flyer or brochure, then investing in the correct paper is a must.
