Erstaunlich genug, attestiert er dem Sigma hier leichte Vorteile gegenüber dem Nikkor.
Das klingt auf jeden Fall sehr gut, vor allem in Anbetracht des Preises. Allerdings, bin ich mir nicht sicher, ob das Sigma wirklich Vorteile hat, denn dieser Abschnitt, wäre für mich schon ein deutlicher Negativpunkt.
BUT...One Noticeable Idiosyncrasy! Part way through the test period I had occasion to shoot some close-up shots of squirrels with both lenses mounted on a D500 (both with and without their respective teleconverters). Think "full-frame shots" and think SHALLOW depth-of-fields (or DoF's). During this time I was shooting in short, high-speed (10 fps on D500; 12 fps on D5) bursts. And, when scrutinizing the shots, I noticed that with the shots taken with the Sigma 500 there was some inconsistency in focus between images captured within a single high-speed burst (when the subject is absolutely static and the camera is not moving). That lead me to shoot several sets of test shots to see what I could learn about this "focus shifting" between frames in a high-speed burst. Here's what I found out:
• The focus shift is normally only noticeable on static subjects
• The focus shift seems to only occur on high frame-rate bursts (greater than 5 fps or so)
• The focus shift is subtle and thus most noticeable on shots with very thin DoF's (e.g., close subjects)
• The focus shift pattern is often as follows: first shot sharp; second shot soft (under the focus point); third shot sharp, etc.
• The focus shift is independent of the OS and AF settings (both those that are adjustable on the lens OR through customization) - it occurs in all AF or OS modes.
• The focus shift occurred on both D5 and D500 bodies.
• The focus shift did NOT occur when I was using the Nikkor 500mm f4E VR
Das alles liest sich aber sonst wirklich toll, ich denke ich werde mir in den nächsten Wochen mal ein Sigma 500/4 OS zulegen
Dann hau rein, ich bin wahrscheinlich demnächst beruflich mal wieder öfter in Hanau. Will das Sigma dann auch mal selber probieren, denn leider gibt es für mich beim Test von Brad ein paar Ungereimtheiten, die aber durchaus beide Objektive betreffen.