To what extent are these studies testing these sub-optimal reading conditions? Are they just testing optimal conditions which could have different results?
A nice bright working area sounds nice. Bonus if it's good light, and not something that will feel unnatural.
Sidenote: I've got a nice big window that I face, and I often want it open, but my room is so dark I have to keep it mostly closed as it overpowers my monitor, eyes, etc.
When selecting light, I pay attention to the temperature of the light (I like 5000K for daylight) and the Color Rendering Index (CRI) which is a measure of the quality of light. Technically you can make "white" with only 3 wavelengths, however the broader the spectrum of light (many wavelengths), the better it shows on reflected surfaces. It's not highly relevant to the topic of eye strain with screens but it's a nice touch that makes the area more comfortable.
Recently, I started exploring LED lights and there are some really good options appearing on the market. I tested some spot lights with a CRI of 92 which look even better than halogens. So when it comes time for me to replace my CFLs, I might end up with a better option.
Personally, I prefer indirect light. So I have light strips which illuminate the wall behind my monitor , and a few other bulbs directed at the ceiling which reflect light back down.
Similar trick to you, I just try to reduce brightness until it looks like a kindle—it’s matte and blends in with other objects in room.
- Better rendering of hues. This comes in nice for things like syntax coloring, or photo editing. The eye is evaluating a color next to the absence of light, instead of next to washed out light.
- Less eye strain when ambient light is insufficient. Ideally the brightness of the screen should be within the same range of brighness as the surroundings.
In my home office, I have about 20,000 lumens of light shining in a relatively small space, at a temperature of 5000K. In other words, it's a sunny day in my office regardless of the weather or the time of day. A quick and easy way to figure out if you have enough light (or too much) is to step back and point your cell phone camera at your workspace. Take a photo without HDR mode. Can you make out details of what's on your screen AND its surroundings? For most people, the screen will be washed out because the ambient light is way underpowered. Dark mode is a good response to that situation.
With quality and variable lighting, you can have the best setup: use light mode during the day; switch to dark mode when it suits you, whether it be for a task that works better in that mode or for evening time when you prefer to start sending a signal of sleepiness to your body.