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Message: <blockquote data-quote="matthew_" data-source="post: 3380364" data-attributes="member: 137083">Poorly applied multicoatings in spectacles can cause more light scatter causing loss of contrast. But is it perceivable (to what degree)? Whatever. I'd have the best multicoatings in my next spectacles. What brand is the tested standard? If we have Swarotop in binoculars. What is the best trademark in spectacles (like Alcontop)? I want one where we can find transmission characteristics or actual percentage of light loss and/or transmission.What do you meant by "Things develop rapidly and the plastic lenses generally get better while the mineral lenses don't develop." What "develop"? Did you mean plastic lenses technology are still being developed while glasses are no longer being developed? So different brands of plastic lens have different clarity??About you statement "high refractive index is reached by adding various substances to the polymer mix." I tested my plastic and glass spectacles on all binoculars I can get a handle on. The plastic significantly degrade the contrast. When tested on a Sightron. It's like the Sightron became just Tasco, the loss of contrast even produce lost of details especially in tiny details. The glass lens only affect it very little (which may be related to non-optimum multicoatings perhaps or inherent in the glass.. do they add something equivalent to polymer mix in glasses too?).I wonder if higher diopter (and thicker lens) would produce worse image. Is it right to say that the thicker is the plastic lens, the worse is the effect? If anyone has been using plastic lens here with diopters more than -5.0 or +5.0. Try to aim your binoculars on close up object then switch to focus bare eyes by turning the focusing knob past infinity and compare this to one using your eyeglasses.. you'd be amazed at the difference! If you'd notice this after spending years on the top Alphas.. all those sparkle would be missed all those times you didn't realize the plastic spectacles degrade the views and contrast of small details like the feather texture of birds. If there is one here who has -8.0 myopia and you don't notice any significant loss of image contrast in any bino using your plastic spectacles.. Please let me know the brand and where you have it fabricated. The reason I prefer plastic is glass spectacles are just so heavy especially -8.0 diopters! Thank you.</blockquote>

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