Ok, many people seem not to know what makes a lens L series. So, here it is: A lens will be L series for one or more of three reasons: 1. It contains a Fluorite Element. 2. It contains a UD or Super-UD Element. 3. It contains a ground and polished Aspherical Element (Rather than a moulded or hybrid aspherical element).

However, now there is an exception to this: The new 400mm F4 DO IS is not L series. The initial diagrams of this lens showed no fluorite or UD, so that was why, but the production versions do have a fluorite elment, in addition to the DO element. So, the question is, why is the new lens NOT classified as L series? Are canon to produce more DO lenses, which will be characterised by small size and weight (relative to refractive lenses), and make these into a separate DO series? Since L series isn't based on optical performance, that can not be a reason for the lens not being. Any ideas?

-- Isaac Sibson (isibson@hotmail.com), October 06, 2001

Answers

No doubt this new series is referred to as "DO" (do, re, mi) because it the first note of the scale and will be music to the ears of photographers with the dough to pay for it.

-- Puppy Face (doggieface@aol.com), October 06, 2001.

The initial diagrams of this lens showed no fluorite or UD, ... but the production versions do have a fluorite elment, in addition to the DO element.

If you look carefully, the information originally posted by Canon in September 2000 actually did show a fluorite element in the middle of the lens. See:
http://www.canon.com/do- info/
especially this picture:

Cheers

-- Julian Loke (elan7e-owner@yahoogroups.com), October 06, 2001.

Hmmm....he's right you know...

Ok, I (and I think many other people) hadn't actually looked closely enough to see that (at normal zoom level, it is hard to differentiate the colours).

However, the question still stands as to why it's not L series?

-- Isaac Sibson (isibson@hotmail.com), October 07, 2001.

I agree with the notion that this new designation implies that Canon (still) intends to produce a series of these lenses, all with the DO moniker.

Or...it could be they were anticipating the reactions of Canon users to the initial price: "D'oh!"

***

-- Rod (rod.nygaard@boeing.com), October 09, 2001.

“L” stands for “Luxury” in Canon Speak, while it actually stands for “Life savings” in common vernacular. Perhaps with DO lenses, Canon’s marketing department has decided to forgo the typical corporate spin control, and the DO simply refers to the huge amount of “Dough” (slang for $$$) that these things will cost.

-- Kenneth Katz (socks@bestweb.net), October 10, 2001.