Originally posted by Frogfish The Sigma 500/4.5 doesn't have IS and is still rather large
I assume the Pentax will be lighter than the Sigma because to make it a best seller I think it will have to be in the US$2,000 - 2,500 range. Not the quality of the Sigma, no IS of course, must have ED glass - but WR is something the Sigma lacks and would be a feather in the Pentax cap for very little outlay.
The Sigma has a front element ~10% larger in diameter than a proposed Pentax 560/5.6. Also, there were rumours that it has 540mm instead of 560, making the front element even smaller. That's a huge deal both for weight and price. From what I've heard, they want it around 2500$, maybe a little more. I assume a high demand initially, so I wouldn't expect the street price to be much lower.
What matters even more to me is this: such a lens is lightweight, compared to other solutions. It might be useable handheld. Forget that with a 600/4
.
Lightweight outdoor photo gear is great for nature photographers (Pentax certainly isn't aiming for sport professionals
).
ED glass would be neat, of course. Less than a month until the world finds out
.