Quick question about resetting my blur adaptation

I’m starting off with resetting my blur adaptation. I have high myopia and I wore undercorrected glasses for few years . My plan is to wear full correction contacts for 6 weeks and then switch to first normalised but I made a mistake and bought contact lenses which i can see 20/25 line clear but to read 20/20 line I have to put little bit of effort and time. It’s not that clear. I have -0.50D glasses at my house so I put them on top of my contacts and with them I can see 20/15. So theoretically adding -0.25D will give me full correction and my question is:

Is buying -0.25 higher contact lenses necessary to reset my blur adaptation?

With my current contact lenses I don’t have any blur challange and I will need to make some reductions for my first normalised. I feel like 0.25 or 0.50 reduction from current contacs to meet 20/40 or 20/30 line on a snellen chart.

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To me, it sounds like you’re right where you want to be. If you’re in a world of blur constantly that’s no good, but 20/25 that you can clear to 20/20 sounds just about perfect. If you want a gym analogy, choosing a weight that is way too heavy that you can’t lift (severe undercorrection / world of blur) is no good, and choosing a laughably easy weight (20/15) is also no good.


Since you have high myopia I would say no. Keep those -0.5D glasses and put them over the lenses every now and then to check what you are missing with your 20/25 contact lenses. Do not do it with distance less than 3 meters. Above 3 meters you cannot really damage your eyes with correcting vision to 20/15.
If I were you, at this stage I’d have my main focus on getting the differentials correct for your working hours and using them. Otherwise wear the normalised contact lenses and use that little bit of effort (not muscle but vision awareness) to clear the blur. And if you have a regular walk that includes street signs, shop fronts and number plates, once a week take a 30-minute walk with your normalised, notice as many things as you can, and then repeat this walk on the same route with the -0.5D on top and take note of the differences.
If you are using your differentials correctly and have enough time away from the screens (especially the smart phone screen!) soon your current 20/25 lenses will give you the 20/15 clarity.

If you have daily or monthly disposable lenses, you can buy the next set of lower description and see if that gives a better challenge.
But before you do that check your vision on real life texts not just Snellen. If you use public transport check if you can read the buses’ destination from a satisfying distance, check if you can read the signs at bus stops / stations, train stations, airports on the main displays. If you are in the supermarket, can you see the signs or only if you walk closer than others would. If you were sitting in a meeting room with a projector or in a classroom in the last row of desks - would you be able to see the board / the presentation? Do you recognize people in the streets or do you miss to greet some of the familiar faces? When you walk into a take away or café can you read the menu behind the counter? How sharp are the traffic lights?
It’s easy to get false self confidence on clarity by only using a well-lit Snellen at 3 meters (or maybe at 6 meters)… And that can easily lead to dropping too early and then compensating AF from muscles…
If it is real clarity, not false confidence then order the next normalised contacts and enjoy the new challenge.

The most important is to enjoy the journey as it is a relatively long one (though shorter than it was to build up myopia…). It will be your eyes telling you what’s good and what’s too much of a stretch / stress. Good luck with experimenting!


I have differentials glasses 1.50D weaker than my current lenses (true value not the value of contact lenses) and I have reading glasses +1.50 just in case.

It’s day 2 with current contacts and I take daily walks 2-4 hours and sometimes 1 hour night walks so I already checked how i see world in normal situation. I can see everything fine, sometimes I feel i can clear little bit of blur with blinks but most of the time i have no challange.

Here i have another question. So fi after some time my vision in current lenses will get better and I will see 20/15 line then I will need to take bigger reduction for my first normalised if i decide to set up my baseline on 20/40 or 20/30 line yes?

So in summary. Leave current lenses for few weeks, wear somerimes -0.50 glasses for reference and after that if everything will be good I can reduce to my first normalised lenses yes?


That’s what I would do. Note: because you started with normalised ones straight, those will be your second normalised lenses actually :wink:

The funny thing with eyes is that you drop 0.25D from the correction and that first pushes you back by 2 or 3 lines on the Snellen that actually equals to a -0.5D or -0.75D drop in vision. (The lines above 20/20 on Snellen are -0.25D per line).
When I dropped 0.25D that typically put me around 20/40 first - which meant 20/30ish in good lights daytime and 20/50ish in rubbish lights. After about 2 or 3 weeks this improved to 20/30 - which meant 20/25ish in good lights daytime and 20/40ish in rubbish lights. And then typically you spend another 1 or 2 months getting that down to 20/25 with a good amount of 20/20 moments.

If you were above -8D I would say you could take a bigger reduction, i.e. a 0.5D drop. But as you are around -6D, I think dropping the 0.25D will be enough for a challenge.

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Oh ok so because of my mistake I started with normalised (in fact I feel like I cheated few weeks becasue I can already see 20/25 line with them) and those -0.50 glasses will reset my blur adaptation at the same time? That’s crazy :smile:
This unusual start got me even more confused and I have another questions to make sure I will be doing things righ and I don’t want to make another topic::

  1. So those -0.50 glasses will be only needed for my first “normalised” lenses?
  2. Since my current lenses are serving me as first normalised, my next reduction after 6 weeks should be in differentials and after another 6 weeks reduce to my N2 contact lenses? Is that right?
  3. I want to be careful about my eyes so I will mostly wear my contacts outside and sometimes in a hosue too but when I have online classes (1.5h each) I’m putting on my differentials glasses. I’m doing 20/20/20 rule with them and sometimes I’m spending the rest of the day in my differentials glasses becasue I don’t want to damage my eyes by constantly putting and taking contact lenses off. Is that ok?

Sounds perfect.
I measure my vision on a 6m snellen chart in 670-680 lx. What is your light level?

Sorry for sooo many question but I am curious person by nature :smile: and I want to get it right so bad :expressionless:

Normalised glasses are “training your eyes” to focus. Keep the -0.5D glasses for night driving, or very bad days (gloomy day + tired) or situations when you need to see everything clear immediately, e.g. a live presentation with screen / board.

Since you started using normalised just now, the next reduction should be in differentials. 6 weeks is a recommendation but you’ll need to see if you are ready for it. And once you feel OK with your new differentials you can drop from the normalised again.
These are not strict rules. Observe how your eyes feel and how they respond to the different lights, tiredness, etc.
Some people change differentials and normalised at the same time. The only risk is that if it doesn’t work out you won’t know which change contributed to what. So yes, it is recommended to alternate drops.

Sounds like a plan.

I bought a handheld lux meter as I don’t trust the smart phone apps.
“Good lights” means above 1000 LUX, “rubbish lights” means under 250 LUX. Around my Snellen I measured 500 LUX during daytime and 200-300 LUX in the evening. For reading I prefer lights around 500 LUX.

Don’t worry too much. If you use differentials, keep the screen at a good distance, minimise smart phone and tablet time, take breaks and have outdoor time (partly to have proper distance vision practice and partly to keep you away from the screens) you will see improvements. If you just do the first 3 of these you will already stop myopia progression.


Sorry, I meant Is doing these double walks will be enough for the first normalised period to actually reset my blur adaptation?

This is my medicine for resetting blur adapration, right? Since I made a mistake and didn’t bought full correction and went straight to normalised.

The extra -0.5D will give you the full correction for reference anytime. To be used as a reminder of clear vision or when the type of activity requires it. From first normalised until the last one. Avoid overdosing, but use it when needed.
You should use your normalised more than you use your full correction so in my opinion you did well by choosing this combo of normalised contacts & glasses with -0.5D.

It’s more important to do it than getting it 100% correct first time. :relaxed:
You can always tweak and refine things with your next choice…


Ok, thank you :slightly_smiling_face:
I will do all of this things, hopefully my vision in current lenses gets even better than 20/25 and when it’s time I will reduce it by 0.25 but If it doesn’t put me on 20/40 line I will consider dropping by another 0.25 to get that baseline and get more challange

In today’s walk I found something interesting for me. I tried to clear with blinks far away car plates that i think has some blur and when I blink the image sometime moves and underneath the real image appears double vision. It’s only happening when I focus on that image and blink.

I had something similiar when I found Active Focus in undercorrected glasses that i wore for few years

I hope it’s a good thing, what do you think?

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Short answer: I think it is totally normal.

Longer answer:
You have the lens in the glasses in front of the lens of your own eye on the right side and the same is true for the left side. And you have the brain merging these 2 images (arriving from the 4 variable factors) into 1 perfectly overlapping picture.
You changed the 2 lenses of the glasses - at this point the lenses of your eyes stayed the same, but your brain already had to adjust the method of merging the pictures as they were differently blurry than before. As you are getting used to the normalised your eyes start to improve and poor brain finds itself again having to adjust the image. And this repeats as your eyes can read better and better on the Snellen.
The brain needs time and it may happen that your eyes improve, but your brain thinks the old routine-like merging will be OK and overfocuses resulting in double vision. Or your brain may overestimate the eyes and may not put the 2 clear images close enough to create one image.

So you have a team of 5 to coordinate - of which 2, the lenses in the glasses are passive participants.
I’m now working on the last diopter which means that my team reduced to a “team of 3” most of the time, just the 2 eyes and the brain. I have just posted about the double vision vs. blur here. Others shared their experiences around blur and DV in that thread, too.


That makes sense, thanks

I bought proper reading glasses +1.50 from the optic shop with the same rims as my differentials has and with the same PD and I can see better in them than my differentials…

What did i do wrong?

To understand it better, let me list all my lenses maybe I did math wrong i don’t know…
Right now as you know i have my normalised contact lenses -5.75D so with the true value that will be -6.25D
My differentials glasses are -4.75D and with them I can see an arm lenght
And I have reading glasses +1.50D and with them I can see much more than an arm lenght from the screen, what;s going on?

Honestly, I don’t know.
What I can tell by the sound of it is that your eyes and brain have observed the change to the good old status quo and are busy adjusting.
I’d suggest monitoring the situation - is it permanently so or is it still changing?
If you can drop more, good for you. Sometimes you don’t have to fully understand what happened?
Sorry I can’t be more constructive with my comment.
But I’m definitely interested to hear how it evolves over the next weeks!

Is this good or what? I don’t understand

I have much sharper vision in my reading glasses than with my differentials, like I said before I can see with them more than an arm lenght from the screen but with my differentials glasses i can see what -1.50 difference is, so an arm lenght or so 66-70 cm. Maybe my eyes in contact lenses and reading glasses on top has lees disortion I don’t know any other explenations what’s going on.

I’m so scared of hyperopic defocus that i don’t even put them on for a long period of time. I’m just taking off my contact lenses and putting my differentials on…

Moving away from the “I can’t see - let me put on my glasses - that’s OK” is good, waking from their inactive state your eyes are trying to focus and the brain is trying to give you the best image, and also now you are more aware of your vision, how it is different, how clear and crystal clear are different, etc.

For the differentials vs reading glasses over contacts:
In general people find better vision with reading glasses over contacts simply because thanks to the contacts the peripheral vision isn’t a complete blur, as it is with glasses only. If you are used to wearing contacts, you may feel the glasses give you tunnel vision a bit as you can only see what’s in front of you, the rest is chopped off…
Adding to this the opto made reading glasses may have some additional multifocal or progressive elements built in. If you want to investigate this you can try walking into a shop where they sell reading glasses without prescription (e.g. bigger supermarkets or beauty stores) and try those average reading glasses over your contacts. If you get the same clarity than your differentials may have an issue like quality in general or wrong PD selected; if with the beauty store reading glasses your vision is not the same then the opto added some extras to your reading glasses and the lens is not a simple 1.5D one…

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I tried those reading glasses from a drug store and had similiar effect with them. I will check my differentials if there is something wrong with them