# A different ratio in the differentials

My ratio between my eyes is 0.5 diopters but when it comes to differentials then this ratio is not good and my weak eye feels like it is better with an extra 0.25. I want to make it a ratio of 0.75 for close up and 0.5 for distance only because it feels great that way but I have doubts about doing this. How come every body is doing great with the same ratio on both pair of glasses

Everybody is doing great with the same ratio or with lower difference in differentials. (Most typical being the uncorrected eyes close up and the unequal corrections for distance)
This makes your case even stranger unless itâs your brain lagging behind and not your weaker eye.

Do you have blur or DV when the differentials donât feel good close-up?

My pattern within the 0.25D has always been âblurâ -> âslight blurâ -> âDV with a tiny blurâ -> âDV without blurâ -> âclarityâ.
At certain steps my eyes were so much ahead of the brain, that they produced 2 perfectly clear images that the brain could not merge into one. That was the most maddening experience at times. At distance it was DV with blur so I didnât have the âovercontrastedâ double images that I had at closer distance.
Alternatively, it may be residual from astigmatism? And strongly related to the angle of the lights at your desk. I never wore correction for the 0.5cyl on one of my eyes, but at every step down I had a small battle and had to work extra on the residual astigmatismâŚ

You are confusing the diopter gap with the diopter ratio. We have already had a thread on this, which I cannot find right now. Keeping the same diopter gap in your diffs as in your norms, means that the diopter ratio has actually changed. You can convert the ratios to percentages. It could well be that an increase in the diopter gap in your diffs keeps you closer to the same diopter ratio as in your norms and therefore feels more comfortable

Just a very crude example: one eye is -5 and the other -4. The diopter gap is 1D, and the diopter ratio is 5/4. For your diffs you drop 2 D in each eye = -3 and -2. The diopter gap is still 1D, but the diopter ratio has changed and is 3/2.

5/4 is not the same as 3/2 and you might feel more comfortable with diffs that put you closer to 5/4. For most people with a diopter gap the change in ratio between norms and diffs in not big enough to make a difference, and anyway, lenses come in steps of .25, so you can never get the exact same ratio. But you might be âon the cuspâ and benefit from a change in diopter gap in your diffs.

General rules are useful, but it is even more useful to trust your eyes.

p.s. Found the previous post. And there are some others - use the search function.
https://community.endmyopia.org/t/plus-lens-in-differentials-or-different-diopter-ratio-between-distance-glasses-and-differentials/12112/5?u=ursa

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