I just had an eye exam and the person (not sure if she is a doctor or something else) tried to determine which of my eyes is dominant. She asked me to point at the corner of the ceiling then close each eye (not at the same time obviously) and say which eye gets my finger closest. Problem is I can see both images of my finger when I point at the corner and I naturally line up the corner to be in the middle of the two images. So neither of them is closest. I tried to explain this to her but she didn’t seem to get it. In the end she seemed to get a bit frustrated and gave up. I asked if it is possible to not have a dominant eye. She says “nope, you have to have one”. Smells a bit dubious to me.
You had an eye exam and you are unsure if it was a Dr or not? That said. It is possible but pretty rare. May want to see if maybe you did not see a Dr then try again elsewhere.
If you did it, it’s obviously possible, but though I’m not an eye doctor (or any doctor, just a guy on the internet really) it seems like a test with a lot of room for error if not done correctly.
If I do the pointing quickly, without thinking about it or adjusting for seeing two fingers, which I do also, I seem to invariably point with the left image (so right eye), even though that’s not even the finger that appears the most “solid”.
Do you genuinely point with the mean of the two fingers if you do it quickly without thinking and readjusting?
I don’t know and I think I will always consciously centre things now.
You should be focused on the corner, not on your finger(s). If you’re focused on the corner, you shouldn’t be able to distinguish two fingers. It should be just be a blurry mess, really. Now close one eye and focus on your finger with the corner in the background. Now use the other eye. Which is more closely pointing at the corner of the ceiling?
Even when focused in the distance it’s perfectly clear to me, if out of focus, that there are two fingers.
These tests indicate that not everyone has a dominant eye in every circumstance:
I’m another person without a dominant eye. If I focus far away and raise one finger on an outstretched arm towards my center of vision, I see two equally “semi-transparent” fingers. My brain can switch back and forth between seeing the fingers or what is behind the fingers.
If you look into the ocular of a microscope or telescope, or the peephole of a door, which eye do you use? That’s your dominant eye.
This seems like a more useful test. I always use my left eye for this.
What’s funny about that test is. If I look through a peephole, I use my right eye. If I do the test in the OP, I get my left eye as a result. I seem to do both consistently, though.
Don’t use your finger. Touch your index fingers and thumbs together, make the “L” shapes so that it forms a diamond between them. Find an object a small distance away: a wall clock, a small painting, a dead fly, whatever. You may have to move around so that you’re not seeing double too much while focusing on two planes. Narrow your aperture so that it’s framed well, then alternate closing eyes. Whichever makes it “jump” when closed is the dominant eye.