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Flat multicoating & Argon (1 Viewer)
- Thread starter Spartan J
- Start date
My view:
Indifferent (see https://www.cloudynights.com/topic/695272-nitrogen-purging/?p=9999593, there are currently entire threads about this subject).
Canip
henry link
Well-known member
"Flat Multi-coating" is the marketing term that Vixen uses for its best 7-layer anti-reflection multi-coating (not something new). The chart on page 4 of the Vixen catalogue below shows why they call it flat, or more accurately claim that it's flat. If you believe the chart Vixen's Flat Multi-coating allows for perfectly linear 99.9% transmission at each glass to air surface over nearly the entire visible spectrum. That would be about half the loss of transmission at each surface compared to anybody else's multi-coating.
The other two curves in the chart could be pretty accurate for those coatings matched with a single glass type of just the right refractive index, but I've got my doubts about the accuracy of that straight brown line at the bottom, even with a perfect glass match.
The other two curves in the chart could be pretty accurate for those coatings matched with a single glass type of just the right refractive index, but I've got my doubts about the accuracy of that straight brown line at the bottom, even with a perfect glass match.
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WJC
Well-known member
200203
Good advertising need not be accurate, or even meaningful; it need only be believed. More binoculars are sold based on the laws of advertising than the laws of optics. :cat:
Bill
TXdefender
Well-known member
The idea is Nitrogen and Argon are both inert gases. In binoculars it’s used to purge moisture and not having oxygen likely keeps the internals from oxidation. In my scuba dry suit argon gives about twice the insulation as air. In my binoculars, I can’t tell the difference.
