there is no flourite coating, just lences with fluorite, which are more fragile.
Yeah, well, words mean things.
The Zeiss literature talks about "fluoride lens elements" as in:
"The premium optical design utilizes ZEISS
Fluoride lens elements, SCHOTT glass and ZEISS’s proprietary T-Star lens coatings for optimum color fidelity,"
They repeat this meaningless canard many times. I am not aware of any glass made with
fluoride. I have heard of
fluoride coatings. I am also aware of "
fluorite crystal lens elements" but these are expensive as heck, fragile and the very few people who have them in spotting scope talk about them
A LOT in their sales propaganda. Look at the Kowa Prominar spotting scopes. You will also find
fluorite crystal lens element in top end camera lenses from Nikon, Canon and perhaps others. These lenses go for $8000 and up. If the Zeiss really had
fluorite crystal lens element, they would talk about it a lot more.
I have heard of a single riflescope made with
fluorite crystal glass, and that's an Airbus at over $7000.
I also know that ED and especially Super ED glass has some
fluorite crystals in it, more so in the Super ED lenses, and currently only March scopes use Super ED lens elements in their High Master optical systems.
If Zeiss has finally started using ED glass, they are keeping it a secret. I did read somewhere than Zeiss using Schott glass out of Germany for all the internal lenses and that they use ED glass from Japan for the big external lenses. I place a low credibility rating on that claim; doesn't mean it's not true.
The 40mm tube seems to be rather thin in the cutaway drawings, more in line with the regular 2mm thick walls, thus providing for a wide range of adjustment. Nothing wrong with that, just something of which to be aware. I kinda like the solid 4mm thick walls in the 34mm tubed March scopes.
