This was my first outing with my new Sony FE 100-400mm GM Lens & matching 2x convertor (1.4x ordered, awaiting stock). This means that I now have native Sony FE lenses covering all of the ranges that I currently use. In the short time that this lens has been available it has received excellent reviews that have indicated that optically it matches or exceeds the equivalent Canon lens while providing the advantages of a native lens in providing access to all of the focusing modes available on a Sony F/FE camera as well as faster and more reliable focusing. I was therefore hopeful/confident of the performance of the lens, though was less sure how it would perform with the 2x convertor. Most early comments indicated that the 1.4x convertor works well with this lens, with little image degradation however comments on the 2x convertor indicated that it degrades image quality. My experience with the Canon convertors had not been good, even the 1.4x on the Canon EF 100-400L Mk2 degraded image quality to the extent that I regarded it better to crop.
First, the bare lens did not disappoint, sharpness appears equivalent or better than the Canon, colour and contrast also look good and focusing speed is much improved compared to using the Canon lens on my Sony A7Rii converted with the Metabones iV adapter. In particular all of the phase detection focus points can be used, with the converted Canon lens only the centre (~50%) band of points would obtain focus, those to the left and right of centre (in landscape orientation) would not focus with converted telephoto lenses. In addition focusing using contrast detection, which occurs whenever the lens is set to an aperture smaller than f8 seems to be fast, much faster than when using converted glass and faster than any of the other Sony lenses (like the EF 70-300mm G). When in continuous focus mode and using contrast detection you can see in the viewfinder the lens constantly hunting slightly in and/out of focus, though it seems to only take a picture when in focus; though this is likely to impact shooting latency times, it will be interesting to see how I get on with this (with the Sony EF 70-300 G, I'd found this to be a problem photographing helicopters when in order to use a slow shutter speed to get rotor blur I often select an aperture smaller than f8, the camera/lens would struggle to maintain focus).
The pleasant surprise came with the 2x converter. Image quality appears to be better than I was expecting. While zoomed in at the pixel level it looses some sharpness compared to the bare lens, however, I would say that when the reach is required the 2x converter is better than an extra crop using the bare lens. In terms of focusing on the A7Rii you only get contrast detection autofocus as the effective maximum aperture of the lens becomes f9-f11 (phase detection only works @f8 and faster on this body, note, the A9 phase detection works @f11 so is usable with this lens/converter). Though, I have to say even with the 2x converter I found the contrast detection AF better than I expected, most of the time it reasonably fast and responsive and above all accurate! It will be interesting to see if I find it usable for my favourite subject aviation/airshows. Anyway, my initial findings is that the 2x converter is usable/useful with the FE 100-400GM lens on the A7Rii body, something I wouldn't have said for the Canon equivalent.
Not too surprising for a Saturday in August Marwell was busy with lots of families (and relatively few photographers). Most of time I was there, there was some sunshine, though there was a period of heavy rain and some thunder. As you can see from the photo's there was a reasonable range of animal activity, though I did skip quite a few of the exhibits.
As seems normal for my visits to Marwell, one of the best photographic opportunities came from a wild bird and not a captive exhibit. This time it was a pheasant in the enclosure with the Bongo antelopes the caught my eye as its plumage looked particularly vibrant, it also stayed relatively still long enough for me to get a number of shots both with the bare lens and using the 2x converter for comparison.
As with recent visits to both Marwell and Jersey Zoo's the Otters again did not disappoint. This time there was only one Otter visible (and it spent much of its time calling out for company, I don't know what if anything has happened to the rest of the Otters, though hopefully it won't be left on its own for long as these seem to be very social animals). Anyway for much of the time it was on the bank near the observation walkway eating (what looked like a crab claw), allowing for a number of close-up shots.
Marwell is also currently hosting the 'Great Brick Safari', which sees an array of animal sculptures each made from 10,000's of lego bricks scattered throughout the zoo. Most of them where very representative and appeared to be very popular.