70-200 f4 ?

[Dave Throgmartin]

i do a lot of wildlife stuff. is it not long enough that makes the 70-200 f4 not the best pick or not fast enough ? if money way not a problem i would just get 600 f4L but that aint happenin anytime soon lol
those pics you posted look pretty much like what im trying to achive. my images almost look ok but if i crop them even just a little bit you really start to see how sharp they arent.

It's not long enough. 70-200 with extender gives you 280mm, just a touch shorter than what you have now. You'd have more latitude to crop, but would need to be close for acceptable results. If wildlife is your goal then you probably want 400mm.

If you want to get to 300mm without spending a bunch of money, there are a lot of people who like the Tamron 70-300 VC. It looks terrible on the site's image comparison tool, but users seem to like it and many get pretty good results with it.

All that said... if you're trying to match the IQ of many of the posters here it could cost you a huge amount of money. Many of the wildlife shots posted are taken with a pro grade body ($3500+) and a 400mm ($1200+) or 500mm ($7000) lenses.

In my opinion, there's something to enjoying the best you can get. Truth told, the 75-300 USM III isn't that great of a lens, but depending upon your budget you can get a better 300mm lens for not a ton of money using either the Tamron, the Canon 70-300 IS, or 70-200 f/4 plus extender. If you can extend your budget to around $1200 you can get the 400mm f/5.6 which is outstanding.

Dave