@ Chosun Juan: Where do you get the idea that metals have better stiffness/resistence to bending stresses???
Temmie, I don't really get the gist of exactly what you're saying - "
better" - than what? are you referring to?
I was referring to plastics,
and of the same volume and form.
It's a function of the materials mechanical properties - Young's Modulus, Tensile Strength, Elongation, Density, etc.
Who knows the exact "receipe" Zeiss uses for the glass fibre reinforced polyamide ('ceptin' maybe the injuneers themselves!) - there's a bucket load of variables there - it obviously meets their spec for stiffness, strength, etc - whether it's up to /or exceeds magnesium's levels or not - there's a whole host of other reasons for jumping one way or the other as well.....
If you've ever seen Clarkson on "Top Gear", you'll know he regards the 'Vette's floppy plastic panels (light though they may be) in much the same vein as he does flappy paddle gearboxes!
Honda has used CRFP (carbon fibre reinforced plastic) in its road race specials for decades, so there's no need for Zeiss or anyone else to stop there.....
Carbon fibre, Carbon-Carbon, Kevlar, etc, etc are different kettles of fish entirely......
that was ma point......there's a bazillion possibilities in both construction and materials........(There's some Astroscope OTA's which are starting to be produced in CF sandwich composites - hold the mayo & I'll have mine without extra weight thanks!
I think that the main reason there isn't more advanced materials engineering in bino's, is because the audience is conservative, well illustrated by some of the comments in this topic.
Can't say that I agree there...........folks just deal with and discuss what's available - pretty hard to see the nice birdies with a dream that doesn't exist......yet.....
Besides optic quality /price (or porro's for some!), the common theme around here is the number of curmudgeonly old codgers (and some just plain codgers) bemoaning the weight of back-breaking "Royal Animals" and binos in general......so the market demand is definitely there.....
If you offered a quality optic bino that was lighter /stronger /cheaper, folks would jump at it like lemmings off a cliff.....I don't think they'd be too worried if they didn't know the molecular structure of the materials involved!
Like most things, its weight of investment that usually determines technology and development......maybe when the titans of wall street are finished r**tin' the joint with their predilection for sexy cdo's, and get back to real businesses....I can finally have my carbon nanotube, printed flourite optics bino's! :cat:
and they'll be a helluva lot lighter than 750grms.....
Chosun :gh:
P.S. Jay, here's the link to the stress effects in prisms (although its more to do with fixing I suspect) - still grist for the mill...
http://www.birdforum.net/showthread.php?t=212971