Why not reduce a little CYL with each SPH?

Q&A: “Why Not Reduce Cylinder With Each Spherical Reduction?” Short answer, no you should not make too many cylinder reductions. Tends to not work out well. Also admittedly an old beard has been spending way […]

Jake Steiner

Feb 28,2020 · 5 min read

Q&A: “Why Not Reduce Cylinder With Each Spherical Reduction?”

Short answer, no you should not make too many cylinder reductions. Tends to not work out well.

Also admittedly an old beard has been spending way less time for a while, talking shop. Eyeball tuning shop, that is. Been quite distracted with behind the scenes, from improving the site, to adding more courses, dealing with personal curiosities like chat bots, starting a bit of a podcast, and so much other stuff.

But. Main thing here is, improving eyesight! Today finally got around to writing a big, long, beardly comment on why you probably don’t want to reduce your cylinder too often.

This one courtesy of our forum:

Find the whole thread over in Le Meow, under the thread title from above. (join link: https://quizzes.endmyopia.org/le-quiz/)

And before we get into this, let’s preface this with a moment of sanity.  I’m not going to give you any “prescription” advice.

Starting with, on what planet and sane universe are clear curved pieces of plastic considered “prescriptions”, anyway.  Answer: on a planet where a thing called ‘lobbying’ exists, and where the lens manufacturing industry spends millions of dollars bribing (yes, BRIBING) law makers to put them in a nice monopoly position to mark up $2 pieces of plastic by a thousand percent.

Anybody says the word “prescription” with any professional gravitas or misguided arrogant lens-seller conviction to an old guru while referring to $2 pieces of clear plastic, likely will experience the wrath of a thousand beard follicles.

It’s all an elaborate ruse to get you to be a good little sheeple and walk into a retail store and not question why you’re paying a zillion dollar markup on some total basic, nothing to it bits of plastic.  

As for my comment on cylinder reduction:

Usually (almost always) when I recommend not to do things, it’s because a lot of people have tried in the past, and it just usually didn’t work.

That’s how most things here operate. If it’s new I let it float around, collect feedback. If there’s some promising progress, I might introduce it more directly (blog posts, video, BackTo20/20 program, depending where it fits best). Then keep a proverbial eye on more feedback. Eventually it either becomes part of general recommendations, or non-recommendations, or more peripheral tweaks or comments.

Not the world’s fanciest system, just more like a filter that operates based on ongoing feedback.

A lot of cylinder reductions definitely don’t work out well at all, for most. If you can reduce a fair bit, you’ll have a good clue up front just by how much you can reduce differential cylinder (less astigmatism symptom up close) in a test lens kit without too much directional blur.

Otherwise though, adapting to change there just takes longer. And it’s hard to do both, blur horizon and active focus stimulus, while also looking at double vision images floating in and out of focus. You get slower spherical gains, you get frustrated, and then you may be tempted to even imagine outlandishness like a holy guru not being all the bearded sagelitude that the world claims.

There’s also something to be said for how the visual cortex (or “you” as a system) train yourself for adapting to challenge. That takes time and good habits and it’s much easier to get into a great routine with well timed spherical reductions that reinforce good habits.

You “throw in” a bit of cylinder reduction once in a while, that the system seems to deal bette with while already having a well established and easy time with the spherical changes.

Also things like, transient astigmatism which will probably happen at various parts of the spherical reduction journey. Everybody seems to get a bit of astigmatism symptom sooner or later (if enough diopters of reduction involved). If you throw actual cylinder reduction into THAT mix, things get even more confusing.

The least amount of focal plane change possible at a time, and the least amount of messing with focal plane complexity. Usually works out best, especially considering the length of the timeline to fully reverse all of it.

As always, lots of “but if’s” depending on your specific scenario. Low myopia high astigmatism, cylinder that’s been high from the start, sensitivity to focal plane changes, contact lens use, general habits, outdoor time (seems to play a role, how much we actually use peripheral viison, vs. central vision that’s mainly in use during close-up). A book could easily be written just on the “but if’s”. Also as usual my general recommendations as a starting point – if you’re a newbie, always best to not start at the deep end of the pool.

There we go.  Starting point!

Of course for a lot more on these topics check out the astigmatism section, diopter topics section, or the guided course options.

Be good to them there eyeballs, and make some 20/20 gains!




Jake Steiner

Reformed stock trader. Kite surfer, pilot, vagabond. Father. And of course - the last of the living, imaginarily bearded eye gurus.

Topic:  Astigmatism