Very nerdy question

[optilady1]

Has anyone compared Avance to Sentinel AR from Walman? They are same category for vsp's AR's, and I know what the propaganda says, and I would love anyone's personal experience with the two products. But I'm interested in knowing from a techie standpoint if the 3 degree difference in the contact angle of Hydrophobic coating makes a difference in long term clean-ability.

And no, I'm not interested in why I shouldn't use Avance, this is the preferred brand at my new job, so telling me how good a no name brand isn't going to help me even if I concur.

Thank you in advance!!!!!!

[Java99]

I've not tried the sentinel. I have tried Walman Ultra, which was supposed to be the same as Crizal Easy, but it was not, sadly.

[ak47]

The Ultra...not so good in my opinion.
I haven't used Sentinel from Walman, but have used Sentinel from Pech (which is the Quantum Innovations product - probably the same as what Walman uses).
The Sentinel is okay, but their Sentinel Plus (new & improved 2013 version) is excellent in my very picky-with-AR opinion (at least the Pech version is excellent).

[Chris Ryser]

But I'm interested in knowing from a techie standpoint if the 3 degree difference in the contact angle of Hydrophobic coating makes a difference in long term clean-ability.

............a superb question.

How can you as a retail optical vendor define and combine a contact angle with long time clean ability ? What is long term clean ability ? I strongly believe that you are taking the word of the labs selling rep that his product is better than the other guy's while both might use the procedure. The contact angle of the run off, of a water drop has nothing to do with the time the layer lasts.

Some people depending on their jobs and nature will clean their glasses every hour, while others will do it once a day. These layers are applied and usually all work, but will be rubbed off in due time depending on the individual wearer, and the lens will get harder to clean either from the middle out to the rim or vice verso depending how the lenses get cleaned.

I have never seen a post on what is being done or offered when the hydrophobic coating is wearing off as they all do sooner or later.
I have never heard of or seen a post of anybody selling or using a replacement product to renew or refresh the existing and worn off hydrophobic coating to help the wearer to get back to an easy cleaning process on his/her existing glasses.

It is easy to strip the whole thing and replace it, but costly and somebody has to pay for it.

There are already some replacement hydrophobic coatings available in small spray bottles that can be sold over the counter to correct the worn off cleaning problem and make the surface super slippery again.

[DanLiv]

Of course all the lab reps tell you their in-house coating is made with the same equipment and is exactly the same as Crizal (lol, if you believe every rep that sells that then there is actually only one progressive lens, one AR, and one frame factory in the world and just thousands of different names for them).

In my experience, and I have handled a few Ultra, nothing is as slick and easy to clean as Avance. But apart from cleanability the biggest difference between all Crizals and just about every competitor is durability, due to the AR stack always and only being applied over the TD2 dip hardcoat. Even if Ultra of whatever other AR's stack is identical to Avance (which I still wouldn't believe) it's just going to be plopped on the factory SRC which will 1) never be as scratch resistant as a premium dip coat, and 2) not guarantee Crizal's adhesion longevity because different ARs will combine more or less effectively with different SRC coats, and no lab does private testing on their house AR with multiple manufacturers to see how well it stands up. Crizal is the only AR I've found that never flakes or peels (only occasionally as a true defect). With every other AR flaking off just seems to be the acceptable standard when a lens gets old enough. I've seen plenty of 10 year old Crizals that, other than user-abuse scratches, are still in great shape and still clean pretty well. I've never seen any other AR last like that.

[Tallboy]

Purecoat is pretty darn good, so is Hoya's EX3 or whatever. Digital Eyelab's Claris HD/Shamir Glacier seems good...Sentinel might be good too, or it might be just Ultra with an extra spray on Hydrophobic layer

But nothing touches Crizal for longevity, barring the few defective batches, it is just a fantastic product. I'm still waiting for a competitor...I'd use it in a heart beat.

[MattHDJG]

In my (extremely biased) opinion Super Hi Vision EX3 and Recharge EX3 are both fantastic products.

[Jstanfast]

Question about ARC and this seems like the perfect post for it.

Zeiss reps are telling me that in the very near future (aka. equipment being installed right now) that next gen purecoat will be matched to the indices of every single job. The question is what will an indices matched ARC actually do better than the other non matched lenses that are matched to a cr-39 lens and still applied to other indices?

[DanLiv]

Question about ARC and this seems like the perfect post for it.

Zeiss reps are telling me that in the very near future (aka. equipment being installed right now) that next gen purecoat will be matched to the indices of every single job. The question is what will an indices matched ARC actually do better than the other non matched lenses that are matched to a cr-39 lens and still applied to other indices?

I thought most decent ARs are already index-matched? Index matching eliminates (well, reduces) the internal Newton ring reflections between AR stack in lens. Essilor gets around this with Crizal stack only needing to be indexed matched to the TD2 (though I still get Newton rings on many Crizals, and every other AR. I would ding my lab's coating for this but I get them on Essilor finished SV too, so even under the best conditions it's not perfect). Purecoat shouldn't need new or special index matching because similar to Crizal it is layered onto their Foundation hardcoat. Maybe they are developing a better index matching technology, or maybe *gasp* the rep didn't actually know what he was talking about.

[Tallboy]

Its about the Hardcoat being index matched to the lens substrate, not the AR Stack to the Hardcoat.

The only two ARs I know that currently index match their hardcoats to the substrate are Hoya EX3 and Digital Eye Labs Claris HD.

Some ARs get it close though, Crizal being one of them, and some are TERRIBLE, they have newtonian rings like saturn.

The phenomenon is not isolated to AR lenses, it can be seen on regular lenses with scratch coat applied as well.

[DanLiv]

The only two ARs I know that currently index match their hardcoats to the substrate are Hoya EX3 and Digital Eye Labs Claris HD.

Interesting, I specifically asked DEL whether they dip hardcoat prior to AR and they told me no, factory SRC only. Maybe it's new, they do have Claris HD Plus now.

[Tallboy]

Interesting, I specifically asked DEL whether they dip hardcoat prior to AR and they told me no, factory SRC only. Maybe it's new, they do have Claris HD Plus now.

Yeah it was the new one (the plus I think) The one they make using the same AR chambers they are making Shamir's Glacier on. Excuse my ignorance, I meant the newest Claris Plus HD

[icmor]

We have used a coating from a lab in Traverse City, Mi that was an outstanding coat. It was extremely difficult to get a blocking pad to stick to it for edging, but it rarely scratched. The lab was purchased by Walman, and I was told by the Traverse City lab rep that Walman was changing over to their formula because it was so good. The original coating name was ExceedXTC. This may be the same coating you're talking about. If it is, it's excellent!

[D_Zab]

Sentinel Plus UV used by Walman is a completely different product then their old Ultra brand. Walman discontinued Ultra because they had a number of problems and went with Sentinel because of it's established reputation. (A number of different labs also use Sentinel products, see ak47's post.)

Crizal Avance and Sapphire have a Bayer measure of 12.9 and a contact angel of 116 while Sentinel Plus received a Bayer of 13.84 with a 112 contact angle so if you go by colts testing its more scratch resistant while slightly more difficult to clean. (Crizal easy has a contact angle of 110 if that helps for reference.)

Exceed XTC is a coating made by Toledo Optical, it is not the same coating as Sentinel but it does have an excellent reputation.

[Chris Ryser]

But I'm interested in knowing from a techie standpoint if the 3 degree difference in the contact angle of Hydrophobic coating makes a difference in long term clean-ability.

The contact angle has nothing to do with clean ability, it is the angle where a drop of water rolls off it you are interested in that. If your hydrophobic angle runs off in a near flat angle, or if it does take a few more degrees it just means that.

It has nothing to do with abrasion induced, by cleaning, which is the real culprit working against a longer live of the top coat. No abrasion at all and the hydrophobic coating will last forever and with it the AR coating underneath, whatever name it has been given by some manufacturer or lab.

Scratched lenses are as old as humanity has seen glasses. The only unscratched glass I have ever seen is the glass over my "Rado' watch that I have been wearing 24 hours a day for 18 years and there is still no sign of anything.

Scratching lenses comes from removing the dirt and dust from the lenses in a way it should not be done, and not improving the hydrophobic coating, which is there only to fill the gaps of the AR coating. If you look at it under a microscope, it actually looks like the Swiss mountains, valleys and mountain tips which do the job of the AR coating.

Education of the user is the important thing, not selling a more expensive product or whoever makes it, so that he can be more care less with it.

The use of a good and long lasting anti static agent will work against dust and dirt settling on the surface and adhere to it, and a lot less cleaning will be a needed result.

When eventually the cleaning gets harder, because the filled valleys between the mountain tops have been slowly removed over time, there are now products available in small spray bottles containing liquid hydrophobic materials that can be sprayed on the lens surface and wiped off and the surface by air curing is back to near new condition.

There are always new solutions for problems out there, when the need arises.

[icmor]

Sentinel Plus UV used by Walman is a completely different product then their old Ultra brand. Walman discontinued Ultra because they had a number of problems and went with Sentinel because of it's established reputation. (A number of different labs also use Sentinel products, see ak47's post.)

Crizal Avance and Sapphire have a Bayer measure of 12.9 and a contact angel of 116 while Sentinel Plus received a Bayer of 13.84 with a 112 contact angle so if you go by colts testing its more scratch resistant while slightly more difficult to clean. (Crizal easy has a contact angle of 110 if that helps for reference.)

Exceed XTC is a coating made by Toledo Optical, it is not the same coating as Sentinel but it does have an excellent reputation.

I'm not familiar with Toledo Optical, or their coating called Exceed XTC. So I won't try to argue that point. My Walman rep from our Traverse City lab was in yesterday and confirmed that Walman is indeed using Traverse City's coating (formerly Exceed XTC) and have added UV to it. It is the Sentinel Plus UV.

[D_Zab]

I'm not familiar with Toledo Optical, or their coating called Exceed XTC. So I won't try to argue that point. My Walman rep from our Traverse City lab was in yesterday and confirmed that Walman is indeed using Traverse City's coating (formerly Exceed XTC) and have added UV to it. It is the Sentinel Plus UV.

You are correct, I just found out about that today actually. Thanks for the heads up!

[Tallboy]

VSP's Unity Elite has similar Bayer numbers to those posted here for the XTC/Sentinel UV AR. Slightly higher Bayer scratch resistance than Crizal and a 112 contact angle.

Unity Elite does not hold up the same way as Avance or Sapphire do. Not saying that the XTC/Sentinel would have the same issues as Elite, I just don't get psyched up for Bayer numbers and contact angles like I used to.

[rbaker]

The contact angle has nothing to do with clean ability, it is the angle where a drop of water rolls off it you are interested in that. If your hydrophobic angle runs off in a near flat angle, or if it does take a few more degrees it just means that.

It has nothing to do with abrasion induced, by cleaning, which is the real culprit working against a longer live of the top coat. No abrasion at all and the hydrophobic coating will last forever and with it the AR coating underneath, whatever name it has been given by some manufacturer or lab.

Scratched lenses are as old as humanity has seen glasses. The only unscratched glass I have ever seen is the glass over my "Rado' watch that I have been wearing 24 hours a day for 18 years and there is still no sign of anything.

Scratching lenses comes from removing the dirt and dust from the lenses in a way it should not be done, and not improving the hydrophobic coating, which is there only to fill the gaps of the AR coating. If you look at it under a microscope, it actually looks like the Swiss mountains, valleys and mountain tips which do the job of the AR coating.

Education of the user is the important thing, not selling a more expensive product or whoever makes it, so that he can be more care less with it.

The use of a good and long lasting anti static agent will work against dust and dirt settling on the surface and adhere to it, and a lot less cleaning will be a needed result.

When eventually the cleaning gets harder, because the filled valleys between the mountain tops have been slowly removed over time, there are now products available in small spray bottles containing liquid hydrophobic materials that can be sprayed on the lens surface and wiped off and the surface by air curing is back to near new condition.

There are always new solutions for problems out there, when the need arises.

I would refer you to: http://web.mit.edu/nnf/education/wet...y/wetting.html