On 14/11/2013 6:28 AM, CollinB wrote:
Anti-reflective coatings work by cutting the unwanted
reflection/scattering/diffusion of light (where it should not go) at each
and any air-to-glass surface. So the coating has to be where it can do its
work, i.e. on each and any air-to-glass surface. Perhaps even between
glasses of different refraction indexes. A filter in front of the whole
lens
cannot do that.
Dario
Of course it can. Just not nearly as well or in the same fashion.
Not all that the HD coatings does is anti-reflective.
I suspect some of it is color-correcting as were the different SMC
variations.
Collin, you can put the best filter in the world on an uncoated lens,
and you will get flare because of internal reflections. All a coated
element can do is keep reflections off of the element it is applied to
at bay. Once the light has moved to another piece of glass, it's a whole
new ball game.
Lens coatings are primarily for flare protection. Any color correcting
they do is secondary, though possibly by design.
bill
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