Pixels, as we know, are the small, usually square dots on a grid that make up a digital image. The way pixels are measured is in pixels per square inch or PPI. PPI is how many pixels per one inch are viewed on a digital screen. Generally speaking, the more PPI you have, the sharper your image will be, but this is only true when viewed on a screen.
On the other hand, DPI or dots per inch refers to how many pixels per one inch are viewed when printed. If you've ever tried to enlarge and print an image that was originally much smaller, the image probably came out looking stretched and blurry. Just because the image was made larger, doesn't necessarily mean that the density of pixels per square inch matched the new size, relating to the dots per square inch.
So, how do we get around that? You start by setting up your canvas before you even begin creating your artwork. Whether you're working in Photoshop, Clip Studio Paint, Procreate, or any other drawing software, make sure you're setting your canvas size, quality, and resolution to the best settings for printing. Often times, your program will open with your canvas settings being set to 72 DPI, which is quite low. 300 DPI is widely regarded as the best resolution for printing, so be sure to up that DPI before pressing continue.
Similarly, you'll want your PPI of your canvas size to match. What your PPI will be will depend on the size of your canvas in both inches and pixels. Common sizes for prints in 300 DPI are listed in the graph below.
|Print Size in inches||Print Size in Pixels|
|(A5) 5.8x8.3||1748 x 2480|
|(A4) 8.3x11.7||2480 x 3508|
|(A3) 11.7x16.5||3508 x 4960|
|8.5'' x 11''||2550x3300|
|12'' x 18''||3600x5400|
|18'' x 24''||5400x7200|
|5'' x 7'' Postcard||1500x2100|
|24" x 36" Poster||24" x 36"|
|Standard Unisex T-shirt||3600x4800|
Warning! If you start with a canvas size that is too big for your program or PC can handle, your program may lag or potentially crash while you're working. You can either start small and continue scaling up your canvas while working on it, gauging how your program handles the pixel increase as you go, or allowing some bleed room by increasing your intended print size by several hundred pixels. Many artists I know will also use a base minimum of 3300 by 2550 pixels and adjust their canvas later.
What type of file you save or export your image as affects the quality of the print too. For example, raster images such as .jpeg, .tiff, .png are great for screen viewing since the format relies on PPI. Vector images, on the other hand, are slightly more complicated since they are mathematically generated, but resizing vector images is far easier since they aren't as heavily reliant on PPI. Companies will often use vector images for logos, which is why you usually don't see a drop in quality, regardless of how large or small the logo is.
Most artists save their artwork while they're working on it as a .jpeg or a .png and then export it as a .pdf when they are ready to print. This makes sense since the artist still needs to view the image as clearly as they can on their screen while the project is ongoing, but will be able to have a second save of the file that is ready for printing when they are done.
When you are finally finished with your artwork, I highly recommend adjusting the color. Sometimes, after printing, your image might look a bit flat or de-saturated. This is because modern computer and cellphone screens display color vividly based on their internal specs, resolution, and via the RGB (Red, Green, Blue) scale. However, most printers print on the CMYK scale (Cyan, Magenta, Yellow, Key/Black) and, once again, rely more on DPI than PPI.
First, try adjusting the saturation and/or contrast of your image, which will make the colors pop or highlight certain areas. You can also manually play with the levels of an image, pushing and pulling the lights, darks, and midtones by dragging the corresponding points on the levels graph. Then, be sure to set your print settings to CMYK. You'll know if you've accidentally printed in RGB if the colors come out looking dull or too dark. Most art programs will allow you to change the Color Mode you are working in somewhere underneath the Image tab.
Some programs also offer internal filters and effects, which you can play around with to adjust the color and mood of the piece even further. I personally like to add Gaussian Blur to most of my images. Just a dash of Gaussian Blur can help smooth out your lines or blend your colors a bit better. If I'm looking for a more retro feel or some texture, I might add a low level of Noise to the image as well.
If you're working on a specific budget but are willing to make the investment for the long run, you can make your art prints from home! There is, however, a bit of nuance when it comes to making the best prints at home. First, you're going to need a quality printer that is designed for images and colors. The quality of prints from standard office printer usually doesn't measure up to the quality from a printer designed to print photographs. I currently work with a Canon PIXMA TR4520, but I've also read good things about the Epson Expression Premium ET-7700 EcoTank. Both companies have many options are a range of prices depending on your needs, so it's important to consider the specifications and usage you'll need. Since Canon specializes in photography, I highly recommend their printers and their inks. You can save some money by purchasing universal ink cartridges, but since Canon Printers work best with their coinciding inks, it may be better to stick with the same brand of ink and printer for longevity and quality.
The type of ink you'll want to use is also important. There are two types of inks for inkjet printers: dye-based ink and pigment-based ink. Images printed in dye-based inks tend to have more vibrant colors that are truer to the original image, but can fade over time. Pigment-based inks may initially look less vibrant, but the integrity of the image holds up much longer than images printed in dye-inks. I personally use Canon's pigment-based inks that work best with my printer, however, but whether you use dye-based ink or pigment-based ink will depend on what your printing material. For example, if you're using a larger printer and are printing on a t-shirt, you might want to use a dye-based ink over of a pigment-based ink, whereas pigment-based inks are more common for art prints on paper.
This leads us to the last point to consider when it comes to printing at home, which is the type of paper you should use. There are many different types of paper, and variables like the coating, thickness, and texture can change how your artwork is viewed. When choosing what paper will be best for the piece you want to print, consider these options:
- Coating: Glossy will make your colors look extra vibrant, but if there's text in your image then the light reflection may make the text too hard to read. Matte doesn't reflect any light, so it's a great option for images that will be framed behind glass or for black and white images. Semi-gloss falls somewhere in between, giving your image some sheen without too much glare.
- GSM: GSM refers to grams per square meter, and this is how paper is measured. The higher the GSM, the more weight the paper will have. To put into context, most copy paper or office paper is around 100 GSM whereas over 250 GSM can range from thicker poster paper to cardstock. Most artists will print on 300 GSM or higher depending on the product.
- Textured or non-textured: How smooth versus rugged do you want your image to look? This is more personal and will depend on the piece you are printing. For example, if you want something to look more vintage, you might want to air on the side of textured paper.
Finally, while many artists will opt for cardstock, if you want the best possible prints, make sure your paper is acid-free or archival. Archival paper tends to be pricier, but the quality of the fibers and ingredients that make up the paper makes archival paper last longer than your standard printer paper or cardstock. Artwork that is printed in 300 DPI in pigment-based dye on archival paper is considered a "giclee" print, which is of the highest quality and worth more money.
Also, always make a test print before each batch! It's better to scrap one page of paper and ink than to be fifty pages in and realize the colors look all wrong.
If the initial investment for your own printer and supplies is not something that is currently doable, you can opt to have your prints made through a third party POD or Print-on-Demand Service. Outsourcing your prints through a POD may cost a little more by stack than making said stack of prints at home, but you won't have to worry about initially buying all of the supplies and/or managing your equipment. PODs also have a wider variety of large-scale printers and goods to print on, such as t-shirts, mugs, pens, and phone cases. Some PODs that do this include Printful, Printify, and Lulu xPress. You can also go to your local Staples or printing store, but be sure to go over all of your options, see the materials they offer, and ask for a test print before having them run the project.
Before handing off your work to a POD for printing, make sure it's print ready! 1. Make sure the output is 300 DPI or higher 2. Make sure it's a vector image if it needs to be enlarged 3. Save an extra copy of your image in a raster format in case the company asks 4. Check if you've changed your image to CYMK for color accuracy 5. Check the margins or bleed room around your image to see if anything important might get cut off.
You can also go the extra mile by looking into the print profiles that the company is using and trying to match your settings to theirs or by investing in Raster Image Processing Software like EFI's Fiery for Inkjet or Printfab to do the heavy lifting for you. This isn't a necessary step starting out, and some programs like Photoshop have RIP built into them, so make sure you fully understand the rendering and exporting process of the software you're working in.