Are you able to consciously refocus your eye?
By this I mean stare at an object (with one eye), and consciously make it go in and out of focus, whilst always staring straight at it.
I find that I can do this to a certain extent - is this something that most people can do?
Then again, I have weird eyes in general. One has almost perfect vision, the other is really bad (don’t remember the exact prescription, but the big “E” on the vision chart is just a dark blur when I don’t have my single contact in).
Yes. Mentally, I move my point of focus from the monitor "backward" into space -- like an imaginary 3D cursor anchored on my screen, then moving away from me along the ray of my eyesight. Almost as if I was going to peer around the monitor and look for something behind it, except without actual movement. Imagine doing that, and it might help.
It's easier to do with one eye shut than with them both open.
I can also (through conscious effort) expand my pupil size. Looking in the mirror if, instead of focusing on one point, I try to look at a larger area (without moving my eyes) my pupils will expand.
If so, this isn't really what I mean.
I mean with just one eye, being able to consciously refocus that eye. For example, looking at this writing on your screen able to make that go in and out of focus.
If you know any trick to make things sharper that'd be great.
Then again, if your vision isn't perfect there are tricks like placing pressure on the eyeball or squinting which can change the focus, but are probably not too healthy in the long term.
Best advice is to see an optometrist instead. Although, I have found that they aim to correct vision for 6 metres in red-green light. If you're reasonably young and myopic, ask for a slightly stronger minus power to get better blue vision at infinity (at the risk of more eye strain close up). The extra -0.25 makes a huge difference for me, really allows depth perception to "click" properly.
On top of this, one thing that surprised me was the difference in correction between red, green and blue light. The refractive index of the eye varies according to light frequency such that blue is focused approximately 2 dioptres more than red. If your myopic eyes are corrected for red at infinity, you won't be able to focus on any blue light further than 0.5m away! Not really a concern in the natural world but very noticeable in a server room full of blue LEDs or on a screen with blue text on black.
The difference in power between red and green is less but still useful enough for some vision tests. If you can focus on red traffic lights but green ones are blurry, this is why - consider a stronger power as long as it doesn't strain your near vision.
Only trick I know is getting the right prescription glasses...