At first sight, when Canon introduced this lens I though: are they crazy? Seriously f/11 fixed aperture? Then as a wildlife photographer and having some big whites and the new excellent RF100-500 I though: well, for the price let give it a chance and I opted for the RF800 which make for me more sense. Well, despite the aperture where you need quite a lot of light the image quality is surprisingly good. Sharpness and contrast is good, colors are nice and I cannot see much aberrations. Even with RF 1,4 converter that brings the aperture at f/16 is still ok for most of the shots in daylight. I pair it with R5 and R6, choosing the R6 more when the light is less or I need to push more the iso to freeze a moment with hi shutter speed. It is lightweight and compact, ideal for walk around bird hunting or hiking. The collapsible system that shorten the length of the lens is very useful to pack it in the bag. Only one general criticisms is it is not weather sealed (so be careful in harsh conditi