Encouraged by the CL’s performance (and durability) lately, I decided to see how well it would mesh with the Sigma 150-600mm in a serious rather than whimsical morning outing.
Shooting in manual mode with floating ISO, at shutter speeds of 1/800 and 1/1000 (no difference between the two in results), I tackled the usual known targets in excellent light, which gave the setup the best possible chance for optimum performance. The short conclusion: Excellent optics and accurate autofocus, but inconsistent stabilization.
Taking my time shooting around eighty frames on familiar subject matter, autofocus was accurate with both AFs and AFc. But only about 50% of the shots were critically sharp. Moving to a slower shutter speed for a few shots with and without OIS confirmed the issue was the OIS of the lens.
It’s entirely possible that the firmware includes no algorithm for shooting on APS-C. So now I have to do the same test with the SL2-S to see if the issue occurs there. If the issue persists, it will be extremely unfortunate to see such great optics in a zoom hamstrung by subpar firmware.
Why is this important? The slightest wobble that causes fuzzy edges (or worse) can obliterate feather details at fine frequencies (birds at middle to longer distances, depending on critter size). This perfectly explains why some of my friends’ shots with the lens are crisp and detailed, while other shots show feathers as almost textureless.
Aside from my old, reliable 180mm APO/2X combo, which is now in its eleventh year (and second set) of use, it leaves an question mark for a longer and/or autofocus option. I’ve run through literally ALL of the long-enough available L-mount options, and every single one has had one kind of showstopper or another.
It now appears that either I’ll have to choose an entire setup from another mount/brand, and, good as the R6 is, I don’t want to go back to a camera with negative relative reach. OR . . . source a copy of the 280mm APO, for which finding a good copy might entail as much risk as working with a system I’ve yet to try.
Here we go again . . .