Unfortunately, the weather does not play with currently, and thus I could under difficult lighting conditions (clouds, rain) test - the more details, which is dissolving the L version can be seen but in virtually all focal areas. Sometimes more, sometimes less, but tends to always be perceived. Very pleasant is the accurate color reproduction of the L version. In the same lighting condition, the lens provided a significantly more neutral but also high-contrast color reproduction than the version without L.
But the killer feature is absolutely the autofocus. I had an improvement for - hoping autofocus of the 70-300 IS USM - anyway good. Nevertheless, I was completely surprised. The autofocus is racing acoustically almost imperceptible from one end to the other focal length and remains fixed and exactly stand where he hinsoll. The whole thing is not only faster but significantly (!) More accurately than with the non-L version. Under identical (difficult) conditions, the old version is the focal length drove several times off completely, and then meet with a rate of 50%. In the same scenario, the L lens applies to 90%, and at a rate that me only a smile to his face.
One has to be clear that 4.0-5.6 course is not really high speed, for fast action shots where it depends on high shutter speeds the lens is not necessarily suitable - because it is certainly at 70-200 / F4 or even better when 70-200 /f2.8 or a fixed focal length in better hands. In low light the otherwise excellent image stabilizer helps still a good deal further, but at some point of course is concluded.
For concern is that the 70-200 / F4 when using a 1.4x teleconverter (-> focal length to 280) also loses one stop and possibly the autofocus is adversely affected. In addition, the price difference between the rated this lens and the 70-200 / f4 pretty quickly if you've factored in the price of the teleconverter into perspective. So if you really attaches importance to the focal length and can live with the photosensitivity is served super with this lens.
Size and weight to be absolutely clear, as compared to the non-L version, the lens is simple bulbous but no longer. Very comfortable is the internal focus, ie the front lens does not rotate during focusing with. This is advantageous when often times similar Polarizer are to be used.
But why only 4 instead of 5 points? I find it unforgivable that Canon included in a lens in this price range and weighing over one kg no tripod mount and for the original part again 130 EUR (!) Will be due. For a ridiculous metal clamp. That pushes the price-performance ratio and the joy of buying quite a bit.
