Originally posted by normhead No sense in leaving the 77 home, it's pretty light, and it's your only sub f2 lens for low light situations. And it might work with the 1.4 TC if you need an intermediate lens in the 150 range.
I'd agree. If finances permit, I'd also look into picking up the M20mm F/4 for the wide end. It never leaves my bag or vest when I have he K1 because it is a tiny but very effective alternative to the 12-24. They have gone up a bit in price since the K1, but can still be had for under $300. An M 200 F/4 with your rear converter might also be a very cheap and light way to get some reach without much weight. You do lose AF with the M lenses, but they are great for keeping the size and weight down. On the M 20, loss of the AF is far less an issue than on the M 200, because of the extended DOF and hyperfocal point on the M 20. You could just pick up a 50-300, which works pretty well at FF. I am into birding enough that I might still consider taking the DA*300.