I've had the IS lens for three weeks now. It's used with 1Ns. The autofocusing is quicker than the old lens, which was no slouch. I suspect the difference would be more noticeable with later bodies (e.g 3s or 1Vs). I haven't had to use it in AI Servo (Follow focus) mode yet but expect an improvement. Also, it is quieter (though these differences may be due to the age of the old lens).
Optically, there seems to be nothing in it, although I haven't tried a side by side comparison with the old lens. I probably won't, as I don't intend to keep it and all it would really achieve, maybe, is to satisfy some morbid curiosity. (A bit like the recent 21v35 zone metering debate. Incidentally, if you find your camera over/underexposing by a reasonably consistent amount, this can be tweaked by Service Dept. My 1Ns were both about 1/2 stop under). The IS lens seems no more prone to flare than the old lens, which is gratifying, given it's extra complexity. The IS lens shifts focus more than the old lens when zooming, making refocusing essential. The IS function is superb, unquestionably the best so far. I shot a burst(?) of nine frames at 1/20th at 200mm, only two show any shake and one of those is very slight! Doesn't stop the subjects from moving though! Although the additional cost of the IS lens is high (enough to buy a 28-135IS in the UK!) I have already achieved shots not possible before. Also using the 2x Extender produces a useable 140-400 F5.6IS. Hope some of you find this useful/interesting. Craig Z * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
