Darkness Across the Screens

Allergy season has started early this year, bringing a great deal of discomfort along with a little loss of vision. Fortunately there's some relief from the itchy, watery eyes with some over-the-counter medicines. The loss of vision, however, is new.

Late last week I noticed that it was almost impossible to use my phone in a dim room. Even at the lowest brightness, the screen was far too bright to be readable. This has happened a couple of times in my life when over-tired or staring at a CRT screen for too long, but the issue is so rare that I actually had to remember that my eyes would become sensitive to light after staring at a CRT monitor for a dozen hours or more. On weekends I seldom use the notebook for very long as Saturday and Sunday is "family time", and yesterday there weren't any real issues after putting in a full day's work at the day job. However, today the vision problem returned shortly after dinnertime.

One of the things that I've noticed about my eyesight is that things in the periphery are essentially just fuzzy blurs. While our peripheral vision is not designed to provide a high resolution depiction of our surroundings, it was generally decent enough up until the age of 35 to identify the brand and make of a car1. Now I'm hard-pressed to see there's a person next to me without paying a good deal of attention. That said, because the vast majority of my day is spent working with text, I can focus really well on characters that many people complain are far too small to be readable. To make these characters as legible as possible, I've generally stuck with dark text on a white background. This preference started back in the late 90s when I was working a great deal with Visual C++ and Visual Basic 5.0. Microsoft's development tools were all like this; black text with blue keywords and red errors on a white background, and I've generally set up every system I use — including how I write notes on paper with my three pens; black, blue, and red — to follow the same colour scheme2.

Tonight, though, I couldn't stand to look at the screens on my work desk after putting the boy to bed. It's not only that they were too bright; the white backgrounds everywhere were causing my eyes to water and blur. Could this just be exhaustion? Most likely. With all the pollen in the air and a distinct lack of the typical humidity associated with this part of the globe, my eyes are likely expressing a desire to be protected with a pair of closed eyelids. Unfortunately, there's still work to be done.

This is where "dark mode" can actually be useful.

A lot of people who use their computers for most of the day have sworn by dark mode for as long as I've been writing software. There are certainly a number of benefits to the inverted colour scheme, but I've always found it hard to read light text on a dark background, particularly if the characters are in any colour other than white or very light grey. That said, when there's work to be done, sometimes it's better to make do3 with what works rather than not work at all.

Sublime Text, the program I use for the vast majority of my coding work, was the first to get the dark treatment. That helped. Then it was Safari, followed by Outlook4, followed by Teams, then the desktop wallpaper, and finally the websites I use on a regular basis5.

My eyes responded well to this. Better than expected, I'd venture. They're not feeling nearly as tired as before. While I don't know how visible a dark theme will be during the daylight hours, I'll certainly make use of it during the nighttime.

Of course, I'll also make an appointment with my eye doctor when all this coronavirus kerfuffle comes to an end. This could be fatigue. It could be something else. I'd rather give up working with computers for the rest of my life than give up my vision6.


  1. One could probably argue that the key information was subconsciously collected with a rapid, involuntary glance that identified the shape and logo of the vehicle. I'm no expert on how our eyes work or how our brain translates photons into a visual expression of the universe we inhabit.

  2. The one exception to this rule has been the tools I use to write essays and blog posts, where the text is only black and the background is a light grey.

  3. I originally typed "make due", which is supposedly "a historical variant that is no longer accepted". If it's no longer accepted, then why the heck have I been using it my whole life? There's no way it was deprecated after I left college then fully expunged from the language at some point in the intervening years. Language doesn't work that way!

  4. Even after changing Outlook to "Dark Mode", there's another toggle you need to hit to make the email section flip from a white background to a black one. Who thought this was a good idea?

  5. My personal site has an auto-dark mode feature, so long as JavaScript is enabled.

  6. Vision is the one sense that I would never want to lose. Smell? Sound? Touch? Taste? Yeah … I can get by without them. It wouldn't be fun, but it wouldn't be impossible. No sight? That would make many of the things that I enjoy most in life all but impossible.