Quote Originally Posted by Colin


So far, I've really liked most everything about every 'L' lens, with the exception of the 50mm f/1.2, for which I had a love/hate thing going on.


There seem to be a few EF-S lenses which, from an image quality standpoint, 'should' be in the 'L' family. However, for whatever reason, the build quality and full frame compatibility are other qualifiers.


Actually, I'd like the 'L' family to be more consistent between themselves too, in terms of form factor and weather sealing. if they all worked the same, that'd be nice. I didn't really like how the 35L had a different form factor than the 50L and the 85L. i didn't like how the 85L had different focusing than the 50L, and lacked weather sealing. I don't like that the 400mm f/5.6L doesn't have an IS version or weather sealing... if I'm buying 'L', I'd really like things to simply match :P


Part of the reason is that they came out at different times. Many L lenses came out before there were many (any?) real weather-sealed bodies. The 70-200mm f/4L does not have weather-sealing, but the later-arriving 70-200mm f/4L IS does.


I'm not sure what you mean by "form factor"--maybe the shape? Remember that the camera end of a lens is pretty much restricted in diameter. It has to fit on the mount and under the overhanging "snout" that houses part of the viewfinder and the built-in flash (the latter on the xxD and xxxD cameras). The 35mm f/1.4L has a shorter focal length and smaller maximum aperture than either the 50mm f/1.2L or the 85mm 1.2L. The laws of physics will say that the 50mm and 85mm must have larger front lens diameters than the 35mm, thus the bloated look. (Edit: the maximum effective aperture of the 35mm lens would be 25mm; for the 50mm, it's 41.7mm--1.7 times as big; for the 85mm, it's 70.8mm, 2.8 times as big.)


As for the 400mm f/5.6L not having IS or weather-sealing, those were Bryan's main negative points, as well. Problem is, the lens without IS is $1200 at B&H. The normal price of the 100-400mm f/4.5-5.6L IS is $1500--with the current rebate, it's $1400. Putting IS and weather-sealing on the 400mm f/5.6L might raise the price to as much or more than the zoom costs. (For example, the difference between the 70-200mm f/4L non-IS and IS versions is $500; for the f/2.8L versions, it's $650. In both cases, the difference includes weather-sealing, as well. The 100-400mm does not have weathersealing, either.) Few people would opt for an f/5.6 prime when they could get a f/5.6 zoom for the same price. The prime's image quality may be a bit higher, but its minimum focus distance is not as good as the zoom (11.8 ft vs 5.9 ft) and it weighs almost as much (2.8 lb vs 3 lb).


I considered the 400mm f/5.6L before settling on the 100-400mm. For my uses--horse shows, nature, the fixed-focal-length would be too restrictive. While some shots at outdoor shows might use 400mm, most would need a shorter focal length. Bryan has said that a 400mm lens is great for field sports--soccer (see the photos of his girls), football, etc. The problem with horse shows is that the horse is much bigger than a person--most are at least 7 ft long, nose to tail--even longer when moving, especially jumping. The focal length to frame a 10-year-old kicking a soccer ball, at the same distance, might get 1/4-1/3 of the horse. Also, one needs to leave "room" in front of a horse to avoid tension in the viewer, plus, there's often context to be considered, like including a jump the horse is going over.