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Message: <blockquote data-quote="looksharp65" data-source="post: 3380823" data-attributes="member: 83771">The top brands always compete at the highest possible level, and there is not one single brand that stands out. I'd guess that the German brands Zeiss and Rodenstock can provide transmission characteristics, but that might be true for other brands as well.Any smear, dust or raindrop/fog will reduce the contrast a lot more than the difference between the best and the worst multicoating.When I'm at it, this reminds me about the fogging problem caused by breathing. The image loses contrast significantly and the colour bias turns towards brownish like an old Jena Notarem roof or worse.It might be intriguing to learn that the devices used for applying the multicoatings are exactly the same regardless of the brand names of the lenses and coatings. This does not mean that the coatings are identical, since the preparation steps may differ, the lens materials differ and the machines are set to different settings for every individual brand. Even within the brands, fine-tuning may be performed to achieve the desired result.That's exactly what I meant.In general, I for safety reasons never advocate using mineral lenses. Dropping and breaking them may lead to a personal disaster.But this does not preclude the possibility to have one pair of mineral lens spectacles, dedicated for use with binoculars.Remember what I wrote about the plastic's reduced transparency?If you consider the difference in edge thickness vs. central thickness, you understand that the periphery of the lens will be darker than the centre.Furthermore, and this is true for both plastic and mineral lenses, their Abbe number is more or less low compared to standard lens materials.As a result, they can produce significant chromatic aberration which degrades the image quality. I'm thinking that your plastic lenses have a low Abbe number and your mineral lenses a higher.//L</blockquote>

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