Keep the 1.67 or try the 1.74?

[bubb rubb]

First of all, this is a great forum. It's a shame that I didn't come across this board sooner.

I've been wearing glasses full-time ever since I was a kid and I was hoping to get a few questions answered on hi-index lenses.

My most recent script came in as:
OD: -7.75 sphere /-0.75 cylinder /15 axis
OS: -7.25/-1.00/170
PD: 60

The local chain store filled the script with plastic hi-index lenses called Superview 1.67 SV (~$300 lens only, did I get taken for a ride?).



I wear semi-rimless frames, shown above (46 eye/20 bridge/27 vertical). In my opinion, I don't think it is a large frame. The edge thicknesses came out to ~5.5mm for the left lens and ~5mm for the right lens, which was a shocker from my previous script. They look like coke bottles. I am seriously considering upgrading to 1.74 hi-index lenses or going contacts full-time. I have read some conflicting opinions regarding 1.74 v. 1.67 on the web and wanted to hear what the experts in this forum had to say.

How much can the 1.74 lenses theoretically reduce the current 5mm edge thickness? Should I bite the bullet and keep the 1.67s? Also, how did the left lens wind up being thicker than the right? Are there any 1.74 brands that are more popular than the others?

Many thanks in advance for your help!

[Jacqui]

Keep ther 1.67's , you won't gain much with 1.74.

[High_Abbe]

1.67 at my store starts at $199, AR is 70 and then I would probably give you 20% off so $215.20 for the lenses at my store. And 1.67 should be fine for your RX.

[HarryChiling]

It is going to save you about 10% in thickness without aspherics. Most of these higher quality lenses use aspherics wich would probably save you about another 5-15% in edge thickness. on a 5.5mm lens you would be looking at a 4.7-4.1mm edge thickness, on that scale I would consider it worth it.

[Robert Martellaro]

The local chain store filled the script with plastic hi-index lenses called Superview 1.67 SV (~$300 lens only, did I get taken for a ride?).

That's what I charge (Milwaukee Wi) assuming the latest generation anti-reflection coating. Add $10 for groove if lenses only, $20 for polish. I would think DC would be higher. I do charge by power though.

The edge thicknesses came out to ~5.5mm for the left lens and ~5mm for the right lens, which was a shocker from my previous script. They look like coke

A monocular PD might of 32/28 and would account for the right being thinner and/or the lenses might have been surfaced instead finished (off the shelve) resulting in inconsistent and increased center thickness (thickness center= thicker edge). Power increase = thicker, rimless looks thicker, sharp corners = thicker, front aspheric slightly thinner, bi-aspheric (in the US Sola Vizio 1.66) the thinnest, close to front aspheric 1.74 index.

FYI my program shows a 5.25 to 5.50mm edge using non-aspheric 1.66 with the numbers you posted and assuming a diagonal of 48mm.

Hope this helps,