We have only been using HiVision and Super Hivision....the EX3 is suppose to be 3 times more scratch resistant than glass but im afraid that means it cant flex and expand with the lens when needed...Any body use this AR on the regular?
We have only been using HiVision and Super Hivision....the EX3 is suppose to be 3 times more scratch resistant than glass but im afraid that means it cant flex and expand with the lens when needed...Any body use this AR on the regular?
In theory, it would be VERY hard to achieve a rating of 3 TIMES more scratch resistant than glass. The surface of lens could be harder than its substrate but only to a certain point. All hard coats, as you pointed out, require some degree of flexibility to avoid crazing. If the lens is impacted, some of that impact is transfered to the substrate as a result, its just simple physics. You may not get "scratching" per se, but it becomes "denting" that looks like scratching... and enough dents then the hard coat begins to weaken...
You would have to make the hard coat so thick that its able to absorb the entire impact its self, but then you get to the point that the lens is now safety thick and probably not cosmetically appealing, and expensive, and heavy. Its more hard coat than lens at this point. A synthetic sapphire crystal used on a watch is 3 times more scratch resistant than glass but the cost is enormous... watches with these crystals start at about $500... and that is with a watch face of only < 40mm across. A saphire chrystal the size of an eyeglass lens would be impossible to process (too hard), very very heavy, and cost more than any of us make in a month.
Ask them for data from Colt's Real Life Simulation Test, if they can't provide it I would consider their claims bogus.
Actually, they advertise it as "more scratch resistant than glass" not 3 times more.
http://www.betterthanglass.com/index.php
I have it on my current pair and it took being dropped 6 feet onto broken rock to make a scratch. Glass would also have scratched at that test.
DragonlensmanWV N.A.O.L.
"There is nothing patriotic about hating your government or pretending you can hate your government but love your country."
to clarify, HOYA did not publicly claim the "3 times" number, a rep said they don't claim it but tests show that it is...it may be worth pointing out that rep is no longer with Hoya
So it "might" be 300% more scratch resistant than glass? :bbg:
We having been using the Ex3 since it came out and have been very happy with the AR coat. Hoya claims that in the Colt Bayer test that the EX3 is as scratch resistant as glass. We have used super hi-vision AR previous to the EX3 and have been extremly satisfied with all of the Hoya lenses and coatings. I would like to note that we have used lenses and AR from Essilor and Zeiss and have found the Hoya Coating to perform much better.
Bayer Hardness Test Value for glass: 12
Bayer Hardness Test Value for SX-3: 15
Difference: 3
Perhaps this is the origin of the "3" times difference?
I'm betting.....
B
I am waiting for the rally of posters to come in and accuse Hoya of fooling us to charge us more money and trying to take advantage of it.
Of course, I believe it is just Hoya doing its best to improve its product. But considering the stance that posters take against other companies, you think the same things would be said here.
Amen to that... With the coatings i used i would rate them Hoya = best, Zeiss = 2nd Essilor coming in 3rd between these 3.Originally Posted by sjthielen
The Ex3 is like 15 something on the bayer abrasion test, glass is 12. But like Sharpstick noted earlier it still will not be as durable as glass.
But with all that said the EX3 is one hell of a coating. Now the only thing left for them to do is let me apply it to lenses i produce (custom coat)
I would rate the Seiko Surpass ECP #2 after Hoya, based on Colts RLS testing, it was the second most scratch resistant A/R ever tested by Colts (Seiko was kind enough to give me the raw testing data). The Bayer test only measures initial hardness, where the Real Life Simulation test measures durablity over time. Basically the simulate 3 years of "use" and THEN test how the lens held up. The problem with the Bayer test is that hardness can break down over time, and a harder lens is theoretically more prone to crazing and internal cracking.
I do believe Hoya makes the most durable coatings, but I would like to see the Colts RLS data on the EX3 for a real comparision.
On the Colts data I have been able to get, here is (guestimated) the ranking: 1) Hoya SHV 2) Seiko 2) Zeiss Carat family 4) Essilor Crizal family. There are few A/R's in between according to Colt's but the manufactures have not released the test results. Colts does not release the results themselves, they leave that to the manufacturers, Colt's only releases an anonymous ranking with a score of 5.00 being perfect. According to Colt's anything above 3.50 will have very good durability in normal use.
Can anyone get the REAL Colt's RLS data for Hoya EX3? Durability over time is more important than initial hardness.
I have ex3 on my nikes and love it. However, it only comes on CR39 and trivex at the moment, and is unavailable on their ID progressive. My silhouettes are 1.60 and I can only do SHV on them.
I saw a few test coating yeas ago that acheived these numbers, the problem was cost of the coating was far more expensive than (multiple) lenses. Kudo's to Hoya for acheiving such great results and at least making it under a $100. This approaches the probable limits on current polymers, lenses can't get much harder without causing other issues. I am sure progress is there to be made, but the next important step is to make it more affordable to the masses.
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