Coming from an L glass newbie....and when I say newbie, I'm talking noon today (70-200 f2.8L IS 8) )!!! "L glasss" refers to the Canon L series of lenses and represents the best that Canon produces. If the lens is Canon L series lens it will have an L after the maximum apature...ie F/2.8L. L series lenses produce a much better image than other lenes with sharpness being a key benefit. Check out the image in this post as an example......http://themagicinpixels.com/forum/index.php?topic=3.msg399#msg399 That in a nutshell is what I believe "L glass" to be. Tim....guys....gals.....care to correct me or add?!?!
here's an article i found on L glass.... hope it helps http://www.the-digital-picture.com/Cano ... eries.aspx
Nikon has an equivalent set. I think its the "ED" designation. its the stuff that starts at 800$ and goes up. its just the marketing for the pro-line of lenses. but they come with some cool features. some come with image stabilization. they come with full time manual focus (so you don't need to push a switch all the time) they are bigger and heavier but have a silent motor and are very fast to focus. there is a bit of a cult out there concerning them, kind of like people who love leica M lenses. it is interesting to see someone at the parks with an L lens (they are either bright white or have a distinctive red ring on the lens-hood area) though mostly i see people with the kit lens on their digital rebels. high end nikon lenses will be just as good if not better (i'm thinkin of that 85/1.4D nikon lens which is so smooth its butter) what I'd really like to see is an andsel adams large format camera set up somewhere.