Should I buy an autorefractor?

I’ve been taking measurements with a Snellen chart and with the EM app, but given their subjectivity I think both results are tainted by my own biases. I really want a precise, objective, convenient method to take ~daily measurements of my eyes.

For ~$2k I could get a used autorefractor on ebay or a new one from China.

I’m hoping that with daily autorefractor measurements I could see some cause-and-effect results from lens reductions, changes in my behavior, etc.

Has anybody bought an autorefractor?
Will my results be useless without taking drops to fully relax accommodation?
Am I crazy?

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I considered this myself, but I see two problems with it:

  1. You need someone to operate most professional autorefractors. As far as I can tell, they don’t offer a model that one person can use on themself without assistance. You may have someone else who can administer the exams, in which case this may be a moot point.

  2. All autorefractors have a margin of error when it comes to accuracy. They range from ± ~0.25D on the low end to ± ~0.75D on the high end. This isn’t necessarily correlated to price, but the gap might be larger with some lower-priced models. This is why autorefractor results are used as the baseline and then fine tuned in the chair using a Snellen chart and phoropter.

If you want an additional point of measurement, you can get a much cheaper portable autorefractor from EyeQue. Their VisionCheck product (~$70) is smart phone based and claims an accuracy of ±0.5D. They are working on a more advanced version (VisionCheck 2) which will be out next summer. It is supposed to be even more accurate (~±0.3D). I am planning to pick up the new model when it launches.

If you really want a professional model, EyeNetra offers a professional autorefractor (which can be used solo) that is also mobile based (uses a specifically calibrated Samsung S4) and comes in at $1,300. It offers an accuracy of ±0.38D and supports SPH between +5.5D and -12D. They also offer a pretty decent phoropter that can easily replace a high-end trial lens kit for $750. You could get both for less than even the used ones on eBay. And it comes with a warranty and support.

However, I ended up coming to the conclusion that it wasn’t worth the money. Particularly given the inaccuracy and the fact that the VisionCheck or VisionCheck 2 will offer a similar level of accuracy for a fraction of the price.

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Varakari bought one.
You can search in the forum here for his experiences.
I’d say its for the most enamoured of EMers. Definitely not necessary.

You could just use a small part of that $2k for opthamologist appointments at yearly or half yearly checkups.

There are also even stories that if you ask nicely the opthamologist will let you do it for free. Readings on an autorefractor take about 2 seconds per eye!

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It is my understanding that Varakari bought a ophthalmic biometer (Zeiss IOL Master). That is many steps above an autorefractor. It is meant for measuring things like axial length and corneal radii for intraocular lens patients. Using it for refraction is overkill since it can do so much more.

But an IOL Master is also way more expensive than an autorefractor. Those things start at around US$15,000 or so. You need to be seriously dedicated, have very deep pockets, or have your research funded to drop that kind of money. That said, I’d love to play around with it! :slight_smile:

It sounds like Varakari is using the one he has for documenting any changes in his axial length, perhaps with the intent of publishing the findings based on the data he collects.

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ah! I see. Just googled it. Assumed they’re the same thing.
Still $2k is definitely not in my budget hahaha.

A side note, I’ve spent about $350 USD on my journey so far. new lenses, frames and appointments.

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Yeah, to do this right will require some investment. I dropped a bit more than that so far on a trial lens kit, test frame, and a few pairs of glasses to experiment with until my trial lens kit came in. I have a better kit coming in from eBay so I’ll be sending back the first one, so I should hopefully recoup a bit of that investment. :slight_smile: After that, I can look forward to dropping $10-$30 on new glasses every 4-6 weeks or so for the next 6-8 years. :grimacing:

I’d drop $2,000 on an autorefractor if it was required to fix my vision, but if I don’t have to spend it, I won’t. Particularly when I can find much more cost-effective alternatives.

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@Merlin93 You can have a look at my gains thread. I bulk bought all my lenses for about $3 USD each from China. I think its worth it if you can get rid of your astigmatism first.

Not sure where you live or how to do it from overseas but AliExpress ships internationally

Yeah I saw that one a while back. Nice deal. I particularly appreciated the long line of lenses.

Of course, getting them cut would be the bigger issue for me. This would be useful though if I could manage it though. I have a wide diopter gap to deal with so I’ll be doing a lot of equalization and I won’t be able to reuse my lenses very much. (Based on my plan so far, I’ll be able to reuse like 4-5 pairs of lenses.)

The additional rub is that I don’t know for sure how my eyes will react or how quickly I’ll be able to reduce, so ordering a bunch of extra lenses in advance would waste some money. Of course, at $3 each, that really isn’t that big of a deal I suppose. :slight_smile:

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Nice idea if you can find a roadside lens cutter. Buying one’s own automated lens cutter will increase the cost of that strategy sharply. No opto shop in their right mind would do it for you.

yes. Im in china atm and getting them cut is no issue. No-one cares here. Heading back to Oz soon and have to say I’m a little hesitant asking optometrists there. So uptight. But I’m sure I’ll find one if I ask around enough.

I thi[quote=“Merlin93, post:8, topic:13661”]
The additional rub is that I don’t know for sure how my eyes will react or how quickly I’ll be able to reduce,
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My assumption would be mixing in astigmatism is the issue. That sounds v. complicated to me. You did mention you’re hoping to drop your CYL. If you’ve got no CYL doesn’t really matter if you buy all the lenses or how quickly your eyes react.

Another thing is I bought about 5 frames exactly the same. So I can just pop them in and out with ease. Mix and match as I need.

Also I thought of you the other day. Supposedly I’ve got 0.5 CYL when the optho tested me and she literally didn’t care. She told me I dont need to correct for it if I don’t want to. I was surprised by that.

Btw, we should probably move this thread elsewhere since we’re hijacking the OP’s thread about autorefractors with all this extra stuff. :grimacing:

Yeah, I’ve got 0.5D or 0.75D of CYL in one eye and 0.25D in the other. I really don’t need to worry about the 0.25D since I think that is transient astigmatism. It comes and goes between refractions and the axis moves around, so I don’t think it’s important. My opthalmologist dropped the CYL from 0.75 to 0.5 in my other eye with the most recent Rx, so that is where I’m starting my baseline from. I’m currently wearing diffs based on that prescription, though my own measurements suggest that I’m still overcorrected by 0.5 SPH in my dominant eye (the one with ~0.25D CYL) so I recently ordered another pair to try that out.

I don’t really like the acrylic frames, so I usually go for half-rim or rimless metal frames. That will make changing out lenses much more challenging too. :slight_smile:

Yeah, I’ve tried dropping the CYL completely and my eyes don’t really like that. It felt like I was overcorrected in the eye with the majority of CYL (since I tried cancelling it with spherical correction) and when I dropped the SPH, it felt like it might trigger blur adaption. So my plan is to just start at 0.50 and 0.25 CYL and drop CYL every third cycle or so. I will probably equalize the CYL in both eyes and drop it together when they’re both at 0.25 since that should be super easy.

That said, I will experiment more to find the right balance. It seems like my eyes can still accommodate quite a bit, so this keeps throwing off my trial lens kit measurements from a day-to-day basis.

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The EyeQue is interesting. .5D isn’t super accurate but still might be helpful, especially at that price.

Currently everything points to the direction that there is no direct connection between your daily behavior and your daily eyesight changes. Either there are too many variable or there is too large and unpredictable delay. It does not change the fact that improvement is possible, but for checking the overall trend cm measurements are more than enough.

tl;dr: you can, but you won’t be further than simply using cm measurements.

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Oh wow the EyeQue looks cool, just preordered the one from Kickstarter. I’ll patiently wait and test that before further considering an autorefractor. Thanks for the tip @Merlin93.

Also that’s interesting about @Varakari’s biometer. If anybody buys equipment that they stop using I hope they’ll offer to give, sell, lend, or lease it to someone else in the EM community!

but aren’t they like REALLY thickkk at the high end since I assume you bought low refractive index lenses if they’re that cheap?

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That really isn’t that bad for an autorefractor. It is just as accurate as many of the professional models that opticial professionals use. The majority are in that range as well. It is still more accurate than the ones that come in at the 0.55D to 0.75D accuracy range.

The new VisionCheck 2 model is supposed to be in the ~0.3D accuracy range (I assume it will come in around 0.35D to 0.40D or so), which will put it in line with the more accurate autorefractors, which are in the 0.32D to 0.36D range.

Also keep in mind that an autorefractor is just a tool for objective retinoscopy. It is used as a baseline to begin a subjective refraction to dial in the exact correction you need. They aren’t expected to be perfectly accurate. An EyeQue will get you pretty close, but the rest you need to validate with cm measurements, a trial lens set, or an optometrist’s visit for a proper subjective refraction.

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You’re welcome.

I am backing that kickstarter as well since the new model looks like it has made a lot of improvements over the current VisionCheck, which was way superior to their 1st gen offering from the original kickstarter.

My guess is that the EyeNetra unit will still be superior (in build quality if not accuracy), but for the money it isn’t going to be that much different objectively.

Yeh I got thinner ones for about 5 diopters and thicker ones under that. They look fine.

I got one of the earlier models. Initially I liked it. But if you’re really honest and dont overcompensate, CM measurements are more accurate than EyeQue.

Also alot of people think that EyeQue overestimates and gives you a higher prescription. So when you buy glasses they blow you away with the clarity.

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