Updated August 1, 2021.
Sometimes when I create a digital collage it looks perfect in the preview, but comes out blurry in the final export. Or sometimes MOST of the collage looks fine, but one image element is badly pixelated.
I couldn’t figure out what was wrong for the LONGEST time.
Turns out it was using the incorrect image resolution on a wrongly-sized canvas, with an added bonus of using the wrong file format for export.
Luckily, all those things are fixable using very easy tools.
- Only use high-resolution image elements
- Use images in the right file format.
- Use images with the correct dimensions.
- Use the correct canvas size.
- Zoom in and check your work.
- Forgo filters and image effects.
- Export at the highest quality possible.
Only use high-resolution image elements
When you’re creating digital artwork, you’ll want to use the highest quality images you can get. This ensures that your entire art piece is also high quality.
In basic terms, this means using image elements that are minimum 300 DPI. If you’re planning on creating posters or other large collage pieces, use a minimum of 400 DPI.
Dots per inch refers to the number of dots that make up an image within one square inch. Since we deal with digital images, our “dots” are really pixels– tiny dots of color that make up an image. More dots per inch means higher resolution and a better quality image. The more color dots an image has, the more detail it has, and the better it looks. What that means for us digital collage artists is: the more pixels an image has, the more you’re able to manipulate it and still have it look good when it’s printed out.
>>> PPI = Pixels Per Inch = another way to discuss resolution for digital images.
Not only are digital collages viewed on high resolution computer monitors, but they’re often printed to be shown in the real world. Low quality images results in low quality prints which look blurry or jagged.
I now ONLY use images at 300 DPI (or higher). This is the reason I’m able to stretch and enlarge certain collage elements, because of their high resolutions. If they’re lower-quality, stretching them would make them look pixelated and/or blurry in the final image.
DPI standard resolutions
- 72 DPI: good for websites, only viewing online (faster loading times)
- 300 DPI: good for standard printing, collages no bigger than 11″x18″
- 400 DPI: good for high quality printing, bigger collages
Items digitized by archives and libraries are typically in 400 DPI or more, and in TIF format.
How to find an image’s DPI
On a Mac:
- Open the image using Preview (the default image program).
- Click on Tools > Show Inspector (or keyboard shortcut: Command (⌘) + I). The image’s resolution and DPI should be there.
On a Windows PC:
- Right-click on the image file and select Properties. A new window will pop up.
- Go to Details. The image’s resolution and DPI should be there.
Oftentimes the website you’re downloading from will also list the DPI or resolution of the image. For instance, Pixabay lists the dimensions of their images on the right sidebar. Be sure to download the highest possible quality image available from whatever website you use.
Also, be sure to only use websites that actually offer high quality images. Libraries, archives, and digital art websites all offer high quality image downloads and make it clear how to download them. Some vintage image blogs have great images but they’ve been compressed to 72 DPI or lower, which definitely won’t work for our purposes.
Low DPI vs High DPI example
Here’s an example of a low DPI image versus a high DPI image. This image was downloaded from the Library of Congress website. LOC.gov offers image downloads in different resolutions, and at first it might seem like a good idea to just download the JPG version.
However, ONLY the TIF version is actually high resolution.
Here is a comparison between a JPG and a TIF. Both were downloaded directly from the LOC website. The JPG is only 72 DPI while the TIF is 400 DPI. You can plainly see the “blurriness” and pixelation on the JPG compared to the TIF image, particularly on the “Boston” text on the shirt.
Now, here is the original TIF and a JPG converted from that TIF, retaining the 400 DPI resolution. It looks almost exactly the same, with no pixelation or artifacting. So, it’s obviously better to download the higher resolution image and then convert it to a Canva-friendly format.
Use images in the right file format.
There are several types of image file types, but the ones we use in digital collage are: JPG, PNG, and TIF. These are different ways to display images on the computer, and they have different levels of image compression.
JPG: compresses the image for a smaller file size, so it’s good if you’re limited on storage space. High DPI JPGs can still look good and are fine for digital collage, but it’s not necessarily the best format.
PNG: compresses the image less than a JPG does, so it’ll have a (much) larger file size than a JPG, but it’s more suited for high quality printing. Use PNG if you don’t need to worry about space and want the best quality image/collage. PNG can also have transparent backgrounds, which can be important for certain collage elements.
TIF (aka TIFF): the archival standard for digitizing historic documents and images. It’s a lossless image format, which means it doesn’t compress the scanned image and is very high quality. These files are typically huge in size, so if you need to save space then you’d for sure have to convert the TIF to PNG or JPG.
Generally, you’ll want to use PNG for your digital collage as it’s a good compromise between quality and file size. If you’re making HUGE murals or posters, then you’ll need huge images at very high quality, and so you’ll need to deal with TIF files.
Use images with the correct dimensions.
An important thing to keep in mind that the original DIMENSIONS of an image can affect its final look.
If an image is originally sized at 3″x3″, and you stretch it to 12″x12″ to fit into a background…it will still look blurry even if it’s 300 DPI. Those pixels are only meant to fit into a certain amount of screen space, and while you have a little leeway to stretch and warp an original digital element into a new size, you won’t be able to blow it up beyond a certain point without it looking VERY bad. Generally, I try not to do more than twice an element’s original dimension.
Here’s an example with my piece Ambiance, which I had a LOT of problems making because of using images with small dimensions. Originally, I created Ambiance on Canva’s poster size of 18″x24″. However, when I went to get it printed as a poster, I got a warning about low-quality images.
Since I knew that I had only used images with 300 DPI resolution, it should’ve been fine. However, I neglected to take my digital image elements’ DIMENSIONS into consideration.
Here’s Ambiance (original poster size) and zoomed into 100% perspective. You can see the map background is badly blurred, especially if you compare it to the little cross doodles in the top right.
I double-checked my image and yes, the map background is 300 DPI…but its dimensions are only 6.4″x4″! By stretching it to fit a poster-sized canvas at nearly 3 times its original dimensions, I’d inadvertently created a blurry mess.
For Ambiance, I ended up resizing the canvas to 8.5″x11″ and that fixed most of the issues. Which brings me to my next point:
Use the correct canvas size.
High resolution digital image elements can still look blurry if they’re stretched beyond a certain point– and you’re more likely to stretch them if you’re using an inappropriately-sized canvas.
If you want to use a bunch of 3″x3″ image elements, it makes more sense to put them on a smaller-sized canvas (like 8.5″x11″) rather than a poster or other larger canvas. You won’t have to manipulate their size as much to fit the space and they’ll end up looking much better.
If you want to make a poster-sized collage, make sure you’re using LARGE-sized elements at at least 400 DPI. Match the canvas size to the image elements you want to use, and you won’t have to worry about pixelation or distortion.
>>> For Canva Pro users: you can resize your canvas any time you want. If you make a poster and it turns out to be the wrong size for the image resolution(s), you can use the Resize menu to adjust down. Like I did for Ambiance! Here it is resized into 8.5″x11″ and at 100% zoom:
Zoom in and check your work.
I’m so guilty of NOT doing this that I’m a little embarrassed to admit it. I tend to create my collages from a smaller zoom so the whole page will fit on my computer screen. Usually, this means I’m working at something like 15-25% of the actual size.
What’s bad about doing that is: a collage will look fine on my computer as s tiny preview image, but when I try to print it as a poster, it’s blurry as heck! See: my issues with Ambiance as stated above. I never bothered to zoom into 100% perspective, so I never caught onto the fact that the background was blurry and horrible.
That’s why I’m saying for YOU to do it– so you don’t make my mistakes! If you make a collage at anything less than 100% zoom, be sure to get in there and double-check your work so you can catch any mistakes early on.
Forgo filters and image effects.
This is more specifically for Canva. Sometimes, but not always, applying a filter or effect to an image makes it look blurrier. I think it’s because Canva’s filter process compresses the original image and uploads a smaller, lower quality version. Usually this isn’t a huge deal, especially if the original image element has a high DPI, but it’s something to take into consideration.
If you use Photoshop or other desktop image editors, you probably won’t have this problem.
Export at the highest quality possible.
This is the one area where Canva can cause problems. Canva’s default image export (“Download”) is NOT 300 DPI. Even the “highest quality image” PNG options tops out at 96 DPI: fine for online galleries or emailing to friends, but not for printing as posters or prints.
If you want the highest resolution possible for your digital collage art, download the PDF Print. If your print company doesn’t accept PDF files, you can convert the PDF into a .png or .jpg and it will come out at 300 DPI, which is exactly what you’ll need.
Planning to get your collage printed IRL? Remember that your print size needs to match the original canvas size. You can’t export an 8.5″x11″ piece and send it to a printer to make into a 16″x24″ poster!
If you use a desktop image editing program, be sure to choose PNG and adjust the export settings to “highest quality.”