Jean-Pierre asks in the forum:

Edge of blur for left eye at -1.75 is ~55cm, for right eye 62cm.

I think my left eye is challenged a bit at my working distance of 60cm, while the right one has it easy.

So, should I go to -1.75/-1.5, or should I trust that my left eye will “catch up” ?

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Be kind to your eyes.

We often talk about how you can’t just get rid of your glasses.  Living in the resulting blur does absolutely nothing good for your eyes, or your state of mind.

Equalizing (the process of reducing the difference between left and right eye prescription strength), is a topic that follows the same logic.  We want challenge, so that your eyes get the positive stimulus necessary to get the change we want.

So the question always needs to be:  Does this prescription change provide challenge?

It’s easy to go beyond challenge.  But if your eyes have nothing to focus on, they will stop trying.  There has to be incentive, clear vision has to be somewhere within reach.

Here is what I responded to the question.  Much of this is relevant to you, no matter how much correction you are working with today:

At below two diopters and only 0.25 diopters difference in otherwise healthy eyes, it’s a close call.  Here is what I like to do, to assess:

Take a range of measurements, to see whether you get any closer than a full 0.25 in difference (use the centimeter calculator if helpful https://endmyopia.org/focal-calculator/calc.htm)

Be sure to give it at least two weeks, three even, with good distance and focus pushing habits. See if the gap between the eyes narrows at all.

If not, then allowing for that difference by adjust the prescription is valid. You do want both eyes to remain challenged and participating. When a non equalized prescription helped with this, use it. Once you are another 0.50 lower though, you will most likely want the same diopter in both eyes.

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Anything more than 0.25 difference, consistently, in your centimeter measurements between left and right is, is too much.

Since your eyes take some time to adapt and measurements tend to vary, you want to take the time to make sure a prescription adjustment is appropriate.  But in any case, you are not resolving differential between your eyes by forcing a prescription.  You want balanced bifocal vision, as much as possible.

Update:  New equalizing / patching videos in our Youtube channel.

Enjoy!