I am wondering how these newer optional coatings affect viewing with binoculars.
I don't wear eyeglasses, except for readers, I have noticed you can tell
when someone is wearing these, with the reflection off of the lens.
I suspect this also affects binocular viewing, and so also must affect color and brightness.
Does anyone know more about this ?
Jerry
Chiming in just briefly by request from Jerry. I've had to take a BF break due to health issues related to general overload.
Ergo:
Good AR coatings allow >99% of the incident light to pass through, this number goes for each surface.
The residual reflection is chosen to satisfy the customer's need to see they really paid for something visible. According to a top clerk on one of Germany's major lens manufacturers, the residual reflection could actually be made white, but that there's no demand for it, in fact on the contrary.
Another reason would be to put the brand's "hallmark" on the lenses to easily distinguish them from their competitors.
With few exceptions though, the residual reflection is greenish-turquoise, sometimes with a second in magenta.
In my book, common-sense tells that with a 99% transmission, a residual reflection of a very narrow wavelength span can't possibly affect the perceived colour balance through the lens.
But material characteristics of the lens like transmission at different wavelengths may definitely affect colour balance, in particular with thicker lenses.
I've said this before, but binoculars with >40 lens surfaces and mirror coatings is an entirely different thing. Reaching a reasonably neutral colour balance requires intricate calculations involving glass colour and customised coatings for every individual lens or prism surface.
When I made experiments with a single-side blue photo filter (i think it was 80A) and the Nikon HG/Venturer/Premier 10x32, I got decidedly better perceived colours but at the expense of lower transmission rate.
Two AR coated spectacle lens surfaces can't get anywhere close to that effect.
Conversely, current coloured mirror sunglasses reflect so much of particular wavelengths that a major colour shift can be noted. However, it is not possible to determine how the colour balance of the tinted lenses is without the mirror.
Take care, all!
//L