500mm vs 600mm?

jjl wrote:

Thanks for the feedback & ideas. I have the 100-400 also, and I think I'll still bring that for backpacking trips or other times a really big lens is cumbersome. I'll probably keep the 400f4 DO as well for traveling.

I've thought about something like that Tamron lens as well (there's a similar Sigma), but the tradeoff in sharpness means I'll wind up with images about similar quality as my current setup.

I hear you about dropping so much $ on a lens to take photos nobody really "needs". Though, there are any number of ways to rationalize it. I figure if I'd spent an extra $10,000 on a nicer car than I currently have, nobody would find that odd. So, why not on a thing I really love to do? Anyway, there's a cost for a new tripod & head too... funny how that works!

i mentioned the canon 300mm f2.8 II in my original post because it can turn into a fast 600mm f5.6 by using a canon 2.0x III, which will be razor sharp. i am not familiar with Tamron or Sigma 600mm tele-zooms but by the numbers, they are not near as sharp and brilliant as canon 300mm. when i feel like my canon 600mm is too heavy to take out, i grab my 300mm and 2.0x III tc and go, taking tripod would be optional   something to think about!

i know these are super expensive toys but i also can't put a price on my happiness, i have worked all my life for what? i have small limited responsibility in my life to worry about so why not get something that i always wanted and not regret someday when i am too old?