300mm Lens Reassurance Needed

[Mat Bingham]

Ok my current birds in flight set up and insect setup is the 300mm F4 IS Canon Lens with 1.4TC II on a Canon 7D. If I upgrade to the new 300mmF2.8 will I get mich quicker autofocus than my current setup both with and without the teleconverter? Also how useful is the new 300mm for insects? Could I sell my 300mm F4? Any advice greatlyu appreciated. I have read arties review of the new 300mm. But I have never seen anything about the the 300mm F4 against the new 300mm F2.8. Thanks

[Grant Atkinson]

Hi Mat
I owned two copies of the 300f4L IS, and currently shoot a 300f2.8L IS as my main wildlife and bird lens. I have also used the new 300f2.8L II IS quite a bit. Either one of the f2.8 lenses will AF much, much faster than the 300f4, and the difference will become greater if light is low.
Both of the 300f2.8 lenses are also sharper than the f4, and have more contrast, specially in low light.
Much as I enjoyed the 300f4L IS lenses that I owned, there really is quite a big gulf in performance between that lens and the 300f2.8 lenses, especially when it comes to AF. Adding a converter to the new 300f2.8 (a 1.4x) will still give you a 420f4 lens that still focuses as fast if not slightly faster than the 300f4L IS.
The new 300 is also a bit lighter in weight, and can focus closer than the old one. It is heavier than the 300f4 but that is the only thing area where it loses out to the older f4 lens.
Check out a review here: http://www.grantatkinson.com/Other/R...488363_d8bRNs/
Cheers
Grant

[Mat Bingham]

Thanks Grant read your review. I am going to try the F2.8 300mm tomorrow to see what I think.