Checking in to post a few hummingbird photos. Really enjoyed zhuxyg's shot!
These were taken with the Samyang 135mm lens. It's challenging shooting hummies in flight with manual focus, but catch in focus makes it surprisingly doable. The white background is not photoshopped - the siding under the eave where the feeders are hanging is white and since it was blurred out, it made the background look nice and clean. I did turn up the highlights a tad to get more separation.
Really really loving the K-1 and this Samyang lens is an absolute gem!
On a separate note, I tried shooting hummingbirds with the K-1 and DA*300 with the HD DA 1.4x rear converter. I also tried with the K-3, same setup. The AF on the K-1 was infinitely better about locking on to the birds in flight. The K-3 had a terrible time even finding them and would just rack back and forth most of the time. With the K-1, it immediately saw the birds and then tried to lock focus. Now, it was a bit slow and not always accurate, but I attribute that to the little devils moving around so fast and the tiny DoF I was working with. Just my unscientific findings, FWIW.