Originally posted by cali92rs I had the Sigma 100-300mm f4. It was a pretty awesome lens, but relatively hard to find. It is also by no means small.
I can second the Sigma 100-300 f4 - and yes it wasn't cheap. Handles and balances well on the K-1. AF is fast for a screw drive too - better than on my K5
Here are a couple of images from it with my K-1 taken a couple of weeks ago at Chinese New Year
(see this Flickr album for more
Chinese New Year 2017 | Flickr)
I've also got the Sigma 120-400mm. That works reasonably well too, but I think the Sigma 100-300 balances better.