Bayer abbrasion scale ? Other AR ?

I know the "Bayer Abbrasion Scale" reviews all the top ARs we use but what about stuff like KMARS stock AR, or Optogenics AR24, or Synergy, or Nassau Nalco with AR. How can I get data on these ARs in comparrison ?

:cool:

Be careful just to look at the Bayer test, you might find it strange that some coated organic lenses perform better in the Bayer than an ordinary mineral glass lens i.e."..are harder than glass...". Any ECP with a few years under the belt will know that this does not reflect the real life situation when lenses come back with scratches.

The sandgrains in the BAYER test bounce on the organic lens in a different way than on a solid mineral glass surface. Some manufacturers optimize therefor their organic coatings rather for a good Bayer test, which might have a lesser relation to the real live durability (see my opening statement, mineral glass....).

So, Bayer can only be ONE information out of a range of coating tests, just look up the complexity of COLTS real life simulation test program.

Georg Mayer

Better Best then Biggest

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I know the "Bayer Abbrasion Scale" reviews all the top ARs we use

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Just a point of clarification: The "Bayer test" is not an independent testing organization that seeks to review products, like Consumer Reports, which your question seems to imply. The Bayer test is simply one particular method of testing abrasion resistance using oscillating sand, or a sand-like abrasive material, such as Alundum, which anyone can use if they have the proper testing equipment.

The Bayer testing method is used by many different companies, ranging from independent testing laboratories (like COLTS) to lens manufacturers. However, even independent testing laboratories are paid to conduct the Bayer test on products, so you will generally only see the results for a given product if the product manufacturer, or the manufacturer of a competing product, wants to advertise the test results.

That said, as Georg pointed out, the Bayer test is only indicative of abrasion resistance performance. It represents one particular type of abrasion mechanism: small particulates that wear the surface of the lens from fine scratching. Other abrasion tests, such as the steel wool test, expose the lens surface to other abrasion mechanisms, such as deep scratching.

Neverheless, one benefit of the Bayer test is that it has good repeatability and reproducibility, at least compared to some other abrasion tests, which has made it a very popular test. But even the results of the Bayer test can vary considerably, depending upon the specific test method, variance in the hardness of the lens sample surface, variance in the consistency of the abrasive, and so on.

The other issue is that the Bayer result is presented as a ratio of haze measurements. For lenses that do particularly well in the Bayer test, say above 5 or 6, even small differences in measured haze can result in pretty large differences in the actual Bayer ratio.

Thanks Darryl, That was interesting. I've been conducting skip-bank tests on selected lenses in my lab. Those A/R lenses that slip in the edger or just tick me off get skipped off the bench and banked into the circular receptacle. When i get to 1000 lenses tested I'll publish the results! ;)