Confused by measuring myopia

I am new to the endmyopia journey. I normally run trough life without glasses (already a couple of years), because I hate them. besides, all of them broke :grimacing:. But I wish to see clear again, that’s why I landed here.

I started with the 7 day course. Everything is fine, I’m understanding the well written e-mails and other posts and the audio-visual material and my active focus is already working well :slightly_smiling_face:.
Started measuring, having a little fun with that.
To buy my first normalized and differentials, I thought I should know everything that can be measured. Thus, I went into astigmatism measurement as well. With the DIY Tool on the page. - I know that I still have time buying those till I fought pseudo myopia first, I just already want to get the measuring right.

Now my problem.
when I measure spherical it is about -1.7 left and -1.6 right (Diopters)
when I measure astigmatism the A value is about -2.2 left and -1.9 right. Shouldn’t the A value of the DIY astigmatism measurement be the same as the spherical?

If so, I guess I’m measuring wrong. Perhaps I’m not used to know anymore what clear vision is.
Perhaps I should explain how i measure. For SPH measurement I use the tape measure method with very thin and small letters, that I see the blur “early on”. For the A value of the astigmatism I go backwards till the line is a tiny bit greyer compared to the arrow although I see the line clearly. How is that supposed to be?

I don’t think it’s necessary for answering my questions, but my astigmatism is between 0.50 and 0.75 left and 0.25 and 0.5 right. I just don’t know yet because I only measured it twice yet.

In theory, yes. When you are measuring the cm distance to first blur you may be overlooking or compensating for some astigmatic deformation and moving to overall blur. The DIY tool, because it is based on lines only, may pick up on the first fading of lines sooner than on text. You may find that as you get better at measuring, the two readings will start to align. For me it is actually the other way around. I get a little more distance to first astigmatic deformation on the wheel than on text, but not enough for it to matter… With your low astigmatism it hardly matters, as you will probably be getting rid of that fairly soon, either in the form of a spherical equivalent or a cylinder drop. Quite honestly, I never found the astigmatism wheel a good way to measure diopters of cylinder.

You may get some more useful information in the EM guide to astigmatism we are working on.
Working Group on Astigmatism Guide

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Thank you for that rapid answer! I thought I have an error in reasoning. Thus, this concludes for me, I will still go on with the “normal” measuring for 90 days and compare it every once in a while with the A value of the wheel measurement. Thus, I will see the combination of habit change and my measurement improvement in the and after that 90 days I probably have a proper answer to which values my differentials / normalized should have.

You are unlikely to need diffs with your low level of myopia. Pull your screen a little closer if necessary (but still at an ergonomic distance) and push it out a little further as you improve and need to add a little blur challenge. My feeling is that the less you wear glasses, the better it is, but that only applies to really low myopes.

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