Originally posted by redpit You just need 2 lenses!
For me the answer is on K-1 when I'm close to the action (runway for example) and Crop when I'm far away and want extra reach. The fact though that I don't own a K-3 and K-5's 16.3Mpxl are not many more than 15 from K-1's crop mode I have the lens mostly on my K-1 despite the low frame rate. Quality over quantity
I don't think I could lift two, plus the D-FA 70-200 as well!
I have used DA* 300 and DA*60-250 on K-3 before for airshows, both with and without the HD TC 1.4x. Experience was that I would like a slightly higher hit-rate, I got some acceptable shots (to me) but I would say I had to take an awful lot to get really sharp images.
Can't wait to try the 150-450 for this application.
John