Al,
In fact this review has been done with the B&H lens, they asked this guy to review the lens and put it up on the net...$120K? Thanks I rather buy a sports car + 500 and 600 f/4 IS :eek: and I will still have some cash left :D
The funny thing is that once you get into this size range lenses become very thick and their performance drops (more aberrations) as the weight sky-rockets. But conversely, mirror optical systems get large enough that one can field the light cone easier so they are the preferred system for large optics. The weight is much less and aberrations can be better controlled. All large astronomical telescopes are reflector designs. Cost is much less. There are also off-axis designs so you don't have the doughnut effect. For example, a good quality 1000 mm f/4 reflector can be had for under $1200 (with the central obstruction). Someone just needs to add an autofocus system to some of these telescope systems. In practice, a different design would be better for an autofocus wildlife design, but I'm sure systems in the 100 mm f/4 and larger range could be made for under a few thousand $. (I do have experience in making mirrors and I have published optical design analyses in Applied Optics, a scientific journal.) I think the hardest thing to accomplish is overcoming the perception of photographers that mirror "lenses" are low quality.