# Trying to achieve diopter gap of 1.25 between normalized and differentials

Hi

Currently, I have 0.75 diopter gap between by differentials and normalized. I want to increase this gap to 1.25 dioptre and check whether it meets my needs. Does anyone has experience of doing this? I will have to take either of the two routes, successive 0.25 D reduction in my differentials without a normalized in the middle or 0.50 D reduction. I know that Jake recommends 0.25 D reductions after the first differentials. Thanks.

I donâ€™t think youâ€™ll need to work up to it unless the 0.75 is giving you blur challenge at near. Just set it and forget it.

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If you can afford it, buy two pairs of diffs, with a .25, and a .50 reduction. If the .50 is too much, it will come into use later.

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Forget blur challenge, my laptop is about to fall off behind the desk and I can push back myself way behind, from where I cannot reach my keyboard sliding tray.

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I would probably consider that not a â€średuction,â€ť per se, but an adjustment into the correct amount of blur challenge for one of two sets of lenses.

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If that is the case, why even consider a .25 reduction? The decision should be based on distance to blur and ergonomic working distance, and not on an average or recommended pattern of reduction. Sounds like good news to me.

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Thing is that even though I understand that the science behind this method falls in line with the concept of hormesis. However, I am also way before trying out a new reduction. Now, when I am able to experience it, I will take base my reductions on basis of calculations. I started with a differentials, 1.25 less than my full prescription. I am wearing the second one which is .25 less than the first.

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Whatever you now have as differentials, if you have to push your screen to the far edge of your desk and can barely reach your keyboard to get any kind of blur challenge, either your eyes have improved very rapidly or you miscalculated your diopter needs for differentials from the start.
The 1.25 diopter gap between diffs and norms is again just a recommendation, and some people need less than this and some more.

I am not sure what you mean by this. Do you mean that according to recommendations it is too early to make a reduction? If you are worried about this, it might be a good idea, as Kent suggests, to consider it as an adjustment rather than a reduction.

It was a typo. It is not way, I wanted to write wary.

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Okay, I get it. It is always good to be wary, but you are not married to a reduced pair of glasses. If you get it wrong, you can postpone wearing them and get a smaller reduction to bridge the gap. But if it works well to reduce by a bit more, you will have saved yourself the cost of a pair of glasses.

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Just get them, and the steps in between. If they are too weak, no problem! In a few months they will be just right Differentials are really nice because they become your normalized in the future!

Getting reduced glasses early is not a problem because youâ€™ll need then eventually. Just be sure to pick the right glasses for blur challenge with active focus on any given day. Youâ€™ll likely find the correct set can change from day to day due to natural eye variations and differing capabilities of AF from day to day.

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Not if your axis of astigmatism suddenly makes a major shift. I have a bunch of lenses for the left eye with what is now almost certainly an incorrect cylinder. If there is no cylinder in the mix, itâ€™s a pretty safe bet that all your diffs will sooner or later serve as norms.

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Ah good point hadnâ€™t considered that

I am getting my glasses done from a local opticals. I have cylinder corrections in my lenses. Since, I am aware that I may need change in cylinder corrections, I am not betting on reusing my differentials for normalized. Opticals can fit the used lenses in new frames and new lenses in old frames. So, lets see how much I can reuse.

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One of the things Iâ€™m hoping to gain by minus distance lenses over near work contacts is to have all the astigmatism correction in the contacts, so the driving lenses can be fairly static.

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I am using -1.5 D weaker (lower) DIFFERENTIALS than my NORMALIZED, and is not problem for me.

Sometimes I am using my DIFF glasses, as NORM, when working on computerâ€¦ looking with DIFF in distance,and my vision start to drastically get sharper (with DIFF).

Now I have -3.50 D left & -3.75D right. My DIFF glasses are -2.0D, and I can see with them really clear my PC screen at 60 cm distance. I work at PC 6-8 hours / day.

Stay focused bro.

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Whatâ€™s the difference between diff-a and diff-s?

Typo. I erased DIFF-a & NORM-s. Sorry.

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I just thought you might have a useful variation on the process.

So, is the term â€śdiffsâ€ť local slang or some sort of standard terminology? To me near work is â€śnormalâ€ť and Iâ€™ll want to use near work lenses most of the time, the driving glasses would be â€śdifferentialsâ€ť to me.