Wednesday, June 6, 2012

Superfocus: concerns

Villager posted two comments to my previous post with very detailed information about his negative experience with two pairs of Superfocus glasses, both of which he returned.  He's still waiting for his refund.  This is all too typical these days.

One of the primary reasons I ordered Superfocus was because it emphasized that the entire lens is usable.   Villager contradicts this.  That's something that I will determine as soon as my Superfocus glasses arrive.

All along I have had two concerns, both of which Villager addressed:

1. Looking up from something close to something far.  The issue here is whether the benefit of Superfocus outweighs this known limitation.  My current trifocal progressive lens accommodates this but with its intrinsic compromises: small reading area and some dead areas.

2. The nature of the slider to change focus.  I wonder how easy it is to move with one hand and to quickly achieve a desired focus.  I also wonder how that opening can remain clean and functional.

I often watch TV and read, often on my laptop or tablet or smart phone.  Superfocus will probably not accommodate this habit.  I could, of course, continue to use my progressive lens during this activity and use Superfocus at other times, especially outdoors when I seem to need to switch between distance only glasses and progressive, which I find disorienting during physical activity.

When the Superfocus glasses arrive I will post my views, hopefully each day during my evaluation period.  I may create videos but have not decided.

3 comments:

Villager said...

Regarding moving the slider I found that the easiest way was to put my thumb under the cross piece and use my forefinger on top. I thought it was interesting that the instructions show holding the thumb on one side of the glasses. I didn't like that way at all.

I now realize why glasses are shaped with a convex outer surface and a concave inner surface. That's so when the eye moves around it is always looking "straight out" so to speak. If I drew a tangent to the inner and outer surfaces of the lens they will both be perpendicular to the line established by where I am looking. This is the way distortion is minimized because there is no refractive error when you are looking straight through a lens.

The Superfocus back lens does not create this concave back, convex front shape. The back remains flat or bulges slightly backward. This creates refractive errors when viewing to the sides and it's intrinsic to the design, unfortunately. That's my layman's analysis of it anyway. Don't mistake me for an expert here - just a curious soul.

And as I said before, I believe Superfocus is well aware of the problem because it explains why they claim the "technology" won't allow them to provide a bifocal front lens.

I suspect they actually COULD compensate for the back lens geometry by the way they grind the front lens. It's probably way beyond their expertise though. And it would require the geometry of the back lens to remain very consistent unit to unit. I suspect it does not.

Anyway, I will be most interested in your impressions. I admittedly had very high expectations for a pair of glasses this expensive. What I didn't realize was that the lens in the eye can have all sorts of distortions to the sides because we only look out the exact center of it for our sharp focus area. As soon as you move the lens out from the eye the distortion becomes a lot more evident since it's no longer restricted to peripheral vision.

Patti MacNeil/Confident Calgary Kids said...

Hi,

I just wanted to pop in and add my two cents worth.

I have had my SuperFocus glasses now since last September and have no complaints, at all.

I had countless pairs of readers, went onto to spend nearly a thousand bucks on what were touted as being the best progressive lenses out there - hated them, narrow field of vision (when I was reading it looked like I was watching a tennis match), nausea when I walked or turned my head - things I do fairly often - simply a waste of time.

After seeing the guy on the SF commercial sweep all his glasses off the counter onto the floor (I was dying to do that) I figured I had nothing to lose, I'd know within the amount of time I had to get a refund. I loved them right from the start. I quickly became very accustomed and adept at sliding for each range necessary, my debilitating migraines are gone and I haven't had any issues. I truly haven't noticed the reflection problem nor the distortion at the sides that you talk about.

In fact these glasses are one of the few things I have bought in recent years that delivered exactly as promised. Based on my experience, I can recommend them without hesitation.

Just wanted to put it out there, another opinion on the matter.
Many thnaks
Patti

Villager said...

Patti,

Glad you like your purchase. We all have different degrees of expectations when it comes to vision. The problems I outline above are going to be a bother to some and not to others. I simply pointed them out - not as an opinion but as observations. There's a difference. By pointing them out I hope to provide others some things to look for during the evaluation period.

The most important complaint I have with SuperFocus is that they WILL NOT provide a lifetime guarantee against manufacturing defects. If the glasses spring a leak in two years, then what? Verbal assurances don't cut it. And there are many reports of ruptures. As you may see in another comment on this biog, SuperFocus doesn't always honor its word. You have only had your glasses for half a year so you aren't really able to attest to longevity.

I'm an engineer and I look at a product like this critically. To be completely candid, I think the glasses are kind of junky and I wouldn't take them as a gift. The lenses don't track well. The slider mechanism is poorly designed. About the only thing I really liked was the position of the nose pads. Bad optics, internal reflections and bad tracking coupled with disturbing reports of ruptured lenses should give almost anyone pause. Someone like yourself who spends a thousand dollars for a pair of progressive lenses obviously doesn't think of $800 as a big expenditure. We're not all that financially fortunate.

So, after months of satisfied use you apparently are searching the web for out of the way critical comments about SuperFocus. Why is that? Sincere question. I can think of reasons both good and bad but I'd like to read what you have to say. When I find something I like or don't like I review it and move on.