I was very happy when I purchased my 400mm f/5.6 lens, but with time I realized that it was not as sharp as I had wanted; moreover, many pictures showed a minimal blurring due to camera-lens shake, which was evident also in pictures made using the tripod, unless I used a very short exposure time. For that reason I changed to the 500mm lens, that I've been using for at least 1 month, and I see a great difference. May be I can hardly make hand-held photos of flying birds as I could with the 400mm, but most of the pictures are rasor sharp and it's a real joy to watch them on my monitor. The fine details of the feathers are very clear and therefore I do not regret the high price I paid for this lens. Last but not least: I believed that it is the photographer that makes the picture and not the tools he uses, and probably this is 50% true...but if you want tack-sharp pictures with crisp details, then you need a lens like this!


