I've recently commenced bird photography on a regular basis using various Leica based camera and lens combinations e.g: Leica T and SL with Canon FD 500/4.5 and Canon 300/4L both with FD 1.4x extenders; Sony A7SII with Leica R 560/6.8 and Leica R 800/6.3 Telyt S … including Leitz APO extenders … and have also tried the Telyt lenses with my SL and T. I travel to local wildlife reserves to use their hides and i'm thoroughly enjoying the experience - but I'm limited by all my combinations being 'manual focus.' When focus is 'nailed' I can obtain good results e.g. https://www.l-camera...n-sl/?p=3310700 but other birders' 'hit rates', using their AF equipment, are much higher. The old adage, "It's not the camera (lens), it's the photographer behind it which counts" has some truth in it … but when all’s said and done, nobody could win the Le Mans 24 Hour race driving an outmoded obsolete car. Relatively fast moving photographic subjects, especially at long distance, require fast AF lenses. Leica's Telyt lenses did cater for wildlife photographers in the past but they are not a practical solution nowadays unless you're a masochist. Anyone with common sense realises that AF offers a much smoother and less frustrating approach to bird photography. I'm aware that some professionals still persevere with e.g. the manual focus Leica R 280/4 APO lens and I used one myself with great results - but it was only really usable at relatively close subject distances; for smaller birds at longer distance 'in the wild' (as distinct from my back yard) its focal length is too short. There were high hopes of the Novoflex EOS to SL adapter offering an AF long lens solution for Leica SL devotees - but it has proved to be far too slow in use and not worth considering for wildlife AF photography. Leica Camera AG does not seem to acknowledge the need for a long AF prime or zoom lens(es) for full frame wildlife photographers; their only offering to date is the SL 90-280mm which is just too short for serious 'in the field' bird photography - especially as there are no extenders available. Panasonic seem to have persuaded Leica to cooperate by producing the PanaLeica 100-400mm M4/3 lens and it appears to have sold very well … but Leica Camera AG has not responded or acknowledged the lens' usefulness by including a corresponding 'very long focal length' prime or zoom lens in its SL lens' road map. Others have commented on the lack of SL long focus lenses and it’s not only wildlife photographers whose needs are not satisfied … sports photographers also require AF lenses longer than 280mm. Leica SL camera sales would likely increase very significantly if longer AF lenses were available. Currently their non-availability is a notable SL system shortcoming and more so because there is not even a hint about them in the road map. Maybe when Blackstone’s Leica stake has been acquired by another investor we might see a change of heart and maybe a hint of some longer focal length SL lenses … to tempt all those who so far have not taken the plunge into the Leica FF SL autofocus system.
Meantime, I’m very seriously considering gong down half a notch by resurrecting my 'overcomplicated menu’ Olympus EM1 and acquiring a PanaLeica 100-400mm M4/3 lens … i.e. following in Jaap's and Big Louis’ footsteps.
The PanaLeica 100-400 M4/3 lens’ popularity (and other PanaLeica lenses) also begs the question, “ Why hasn’t Leica Camera AG produced, or badge engineered, a M4/3 ICL camera?” Potential sales could likely justify same.