Bizarre thing occurs at astigmatism wheel

Hello everyone

Yesterday the glasses that i bought one month ago finally arrives.
I had some trouble with the astigmatism data when choosing the parameters at the zenni’s website, so i ordered a -3.25 spherical, and just ignored my 0,75 astigmatism prescription.
I put the glasses on and at first moment appears to be perfectly fine, but after a while my gaze becomes a little fuzzy.

So, last night , i’m took a look at an astigmatism wheel, to measure my astigmatism state, wich is
165° left eye and 180° right and something bizarre occurs: The axis start to change when i’m do AF and sometimes desapears.

astigmatismtest

1 Like

This isn’t too strange if you look into how astigmatism works. See this thread, where a similar question was asked.

You can make sure which type of defocus you’re looking at by using your computer glasses at maximum focusing distance. Then, you’ll only see the myopic astigmatic error; this blur is orthogonal to your axis, so for example it should blur horizontal lines vertically for your right eye.

Optically, the error should never disappear completely. But if you focus back and forth, the brain might sometimes puzzle together the correct image, which doesn’t really mean that your eye can see that well.

To see as much error as possible, you could try a white-on-black test image as well.

4 Likes

@miocardio…To upload images from your device, click the icon in lower right corner. Icon looks like the sun rising over a small and larger mountain.

1 Like