So this is a little convoluted, but I wanted to share some things I've noticed as I've been reading around.
1. DPReview's preview of the K1 has it mounted with a M50 f2. I have a poor copy of this lensthat I got for $10 and use to explain aperture to people. I don't think it is or ever was particularly stellar. There certainly are many better options... What a strange choice.
Special K? Pentax K-1 First Impressions Review: Digital Photography Review
2. Same page near the bottom. The only lenses not requiring stopping down to work well on the K1 in FF mode I believe are the DA* 200, 300, and DA 560. This is good news for wildlife shooters. I've read a lot of concern about them. I was most surprised about the 560. I only wish I had one.
3. While exploring my options and trying to imagine my kit over the next several years, I was researching Nikon wildlife options. I'm having a hard time finding the article again. Essentially it listed every Nikon telephoto option known to man. Then at the bottom it listed Tamron and Sigma options. Beside these it mounts these lenses were available in. This essentially means Nikon, Canon. The thing that caught my eye was that beside the 150-600 zooms from Tamron and Sigma, it listed Nikon, Canon (Pentax and Sony for an additional fee). Has anyone heard of this? If it's true it may be a decent alternative for us Pentaxians. If I can find the article I'll add the link. I'm not even finding it in my browser history. Very strange.
---------- Post added 02-18-16 at 02:28 PM ----------
Yes here we go I found it. Possibly just a error on the writer's part.
How to choose a wildlife lens | Don's Photo Blog
here's what was written
Sigma 150-600mm F5-6.3 DG OS HSM | Sport (Canon | Nikon | Pentax & Sony mounts can be added at an additional cost)
Sigma 150-600mm F5-6.3 DG OS HSM | Contemporary (Canon | Nikon | Pentax & Sony mounts can be added at an additional cost))
Oh and my mistake.. it wasn't mentioned about the Tamron.