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How to create high resolution images for users with low vision

Here are my favorite tips for how to create high resolution images for low vision users - a must have for students with visual impairments!

As a student with low vision, I often encounter blurry, low resolution, or hard to see images as part of assignments, online readings, exams, and during class presentations. One strategy that has really helped me access information visually is learning how to create high resolution images for low vision and advocating for the importance of finding high resolution images for accessible materials, which make it easier for me to use tools like pinch-to-zoom and screen magnification to enlarge details of images. Here are my tips for how to create high resolution images for low vision, and how to locate high resolution images online.

Definition of a high resolution image

A high resolution image is defined as having at least 300 dpi (dots per inch) and can be scaled across multiple sizes for web and print materials, as well as enlarged without any visible pixelation or blurriness. Most high resolution images are 3.5 megabytes (3.5 MB) or higher.

High resolution images typically are saved as Portable Network Graphics (PNG), though JPEG and GIF images can also meet the criteria for high resolution images. I prefer to use PNG files whenever possible, as they have a wide range of colors and compression options, and can be enlarged without sacrificing quality. This isn’t to say that I can’t use JPEG, GIF, or other formats, but I do find it easier to use PNG.

How I view high resolution images with low vision

I prefer to access information visually whenever possible and use strategies like large print, screen magnification, and displaying content on screens that are within my field of vision to access information. With high resolution images, I can easily zoom in to view details, crop images to focus on a specific area, or make edits or annotations to an image as needed without having information appear blurry when I enlarge it. Strategies I use for looking at images with low vision can include:

When it comes to viewing images at a distance (like on the board or when someone is holding up a phone to show me a picture), I usually ask for a copy of the image so that I can view it on my own device. If it’s a friend showing me a picture on their phone, I usually take the phone to look at the image.

Is it better to use color images or black and white images for low vision?

Like the answer to most questions about preferences for visual access, the answer is “it depends!” There’s a common misconception that black and white graphics are the best option for high resolution images for users with low vision, since they have a limited color palette. However, color images are also great candidates for creating high resolution images, especially rich and saturated colors. I actually prefer to use color images myself, because I have normal color vision and can use color to convey or get a quick glance at information.

High contrast and high resolution images are two different things, but they are often mentioned together in conversations about accessible images. Contrast is defined as the difference of color that makes an object (or the foreground) visible against a background of a different color, with a contrast ratio showing the luminance of the brightest shade to the darkest shade. For low vision, high contrast color schemes may involve limited color palettes or removing non-essential colors, while other high contrast color schemes simply make colors easier to see against different backgrounds. High resolution images that are designed for users with low vision often incorporate high contrast elements in some form to make information easier to see.

How high resolution images help me as a student with low vision

Many years ago, one of my teachers asked me why I needed high resolution images if I had “low-resolution” (blurry) vision. Here are four short stories about the impact of having access to high resolution images has had for me as a student with low vision:

The test that failed me

When I was taking an online placement exam, I realized that I couldn’t zoom in on the details of several graphs or charts to get the information I needed for the question. As I tried to enlarge the image, it became more and more blurry, and the patterned background of the coordinate plane made it even more challenging to locate the points and numbers I needed. I also couldn’t use color as a landmarking tool, and all of the areas of the chart essentially looked like a giant blob. Even though I had gotten a perfect score when I took a practice test with images I could enlarge, I got every single question wrong because I couldn’t see the images on the test.

Confidence in calculus

Instead of zooming in on images embedded in a document, my calculus professor shared a folder that contained all of the images for the exam, including corresponding question numbers and/or answers (e.g. “Question4A”, “Question4B”, etc.). These images were screenshots from a graphing software, and my professor had also highlighted lines and points in a contrasting color so I could easily locate them. Because I could enlarge all of the images without having them turn blurry or distorted, I could focus my energy on answering questions instead of straining to see, and got a perfect score on the exam!

This reminds me of a dinosaur!

My teacher put an image on the board and asked everyone in the class to write down details about what we noticed about it or create a sketch of what it looks like. Even when I walked up to the board to get a closer look, I had no idea what I was looking at because a lot of the colors were very similar and swirled together, plus it was very dark. I saw the reflective ground and brown tones of the image, and it reminded me of something I saw at a museum (that also had a very shiny, reflective floor).

The teacher called on me first to share my thoughts about the image and what it looked like, and I delivered a very confident but completely incorrect answer since I didn’t want to admit I had no idea what I was looking at— I thought it was the underside of a dinosaur skeleton, and it was actually Luray Caverns (a cave in Virginia). When my teacher found an HD wallpaper of the same image, it was much easier for me to see that I was looking at stalactites and stalagmites.

Lemon on a pear

I have a post linked below from a talk I gave about accessible memes that was inspired by several people sending me the same image— a blurry, compressed image of a lemon on a pear. It wasn’t until I received the image for the sixth time that I recognized what it was (thanks to a friend adding their own caption), and that people had shared it with me because they knew how much I loved Bon Jovi and the song “Livin’ on a Prayer.” While it doesn’t relate to academic access, I share this story because this was an example of how low resolution images can impact individuals in social contexts as well, especially if they don’t want to ask someone what’s in an image or disclose that they have trouble seeing.

Tips for creating high resolution images with technology

When it comes to creating high resolution images with technology or accessing high resolution images, I find the following tools to be useful for drawing or modifying images without compressing them or making them blurry:

While my website graphics are not visually complex, I use the free Canva tool to create all of the graphics for my website with the exception of my logo because I can zoom in on different areas of the image and use keyboard shortcuts.

Tips for drawing images that will be used for high resolution images

When I was working with an elementary school student, their teacher would often draw images by hand and scan them so that the student could view them on their laptop or an iPad. Strategies that can help with drawing images that can be enlarged easily include:

When I was working with the same student, I would often use digital drawing applications and my Apple Pencil to annotate images.

Tips for scanning high resolution images for low vision

Searching for high resolution images

Several search engines have filters for finding HD or high resolution images, along with options to search for images with a minimum resolution. This can be done by selecting the Filter option on Bing or Tools on Google, and choosing a size from the drop-down menu.

Some examples of websites that have a large amount of high resolution images include:

Another source that has been great for finding high resolution and high contrast images for students with low vision is the Tactile Graphic Image Library (TGIL), which offers free dual media (braille and large print) images and diagrams. I also share several other sources in my post on free braille and tactile images.

What about reverse-searching for high resolution images?

Already have an image and looking to see if it’s available in a higher resolution? Run a reverse search for an image to see if there are other image dimensions available on other websites. A few options for doing this include:

Improving the resolution of an existing image

There are a few tools online and that are available with photo editing applications for increasing the resolution of images and improving the clarity of existing images, including:

Other strategies for creating high resolution images for low vision


This post on high resolution images for low vision is written by Veronica Lewis, M.Ed. and reposted with permission from Veronica With Four Eyes.

Published January 2018. Updated June 2025

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