On the long end, Leica will be compared with Canon/Nikon's 400 mm f2.8 lenses with stabilisation, ultrafast focus and very good optics. These lenses are already expensive, so just imagine the Leica price tag. I would also imagine rather low demands, further increasing the cost (for several of the long APO R-lenses, only 2000 copies were made).
That being said, I would happily let my Nikon gear go the day Leica coffers a 400 or 500 mm SL lens (f4, say) with stabilisation and high-end af and converters.
Thanks everyone for your input, and especially the touched up example from Pete, it looks much better and I appreciate you taking the time to do that. Clearly I need to do some more experimentation to determine in exactly what kind of conditions it happens and how to minimize or avoid it. I’ll try changing apertures and see how that affects it, but in my experience it’s happened all the way down to at least 5.6, but for sure it seems worse at smaller apertures. As soon as I get home this weekend I will experiment and let you know more.
I always use the lens hood. I haven’t tried to tape up the corner vent in the hood, the thought has also occurred to be, but I don’t think that’s the issue because it’s happened in circumstances when the sun was not on that side of the camera.
It does not seem to happen in low light environs. Do you use your lens with an SL? Have you experienced any similar issues? I’m not worried about Leica quality as a whole, I feel they make incredibly high quality products, but I must admit to being surprised about this issue with the 24 Lux/ SL, which is why I wanted to check within the Leica community to see if anyone else is experiencing the same anomalies. I obviously can’t speak to your issues, but I’ve met mostly exceptionally professional and knowledgeable folks in my interactions with Leica staff, from Frankfurt A.M. to Seoul to Los Angeles, and quite a few places in between and I’ve been to some very extreme out of the way environments, from the Amazon in summer to Svalbard in January and I’ve never had any issues with my Leica gear, except for this one thing.
Some of these pics were taken at Glacier national park during the fires last month, so the sky is very smoky/hazy. Here are some links to these pics in Dropbox, these are jpg samples, I'm on the road and don't have access at the moment to the DNG files.