Sigma 12-400 to what?? (1 Viewer)

Me: I am a wildlife photographer and would class myself as a serious amateur with a reasonable rounded knowledge of cameras and lenses.
Currently i use a canon 1D Mk3 with a Sigma F4.5 prime.
That in itself has been a great combination however i plan to upgrade any day now to the Canon 7D Mk2 (keeping the Sigma lens)
In conjunction with this i use a Sigma 120-400mm with either the 1D body or a 50D
For a long while now i have thought that the 120-400mm whilst a good lens isn't fast enough or good enough for a mid range lens.
I am looking for a lens for close up work whereby a 500mm prime would be too long and fast enough to use and track in flight birds and for general use on dragonflies, damselflies, butterflies etc.
Her by lies my problem i just cant decide which way to jump re this lens, mid range prime? mid range zoom? fixed zoom at say 400mm?
I am on a photography day soon with gorillas being the main subject and keen to get the iconic shot of the close up of the gorillas eye.
Its a long winded question but would greatly appreciate any and all replies and advice, especially from anyone that has already done this journey..
Cheers all.
Keith

Personally I would look to your glass first. Whist the 1D3 is "Old Hat" these days it is still a very good camera.
As to the lens - that is a bit more difficult!
Firstly you mention lens speed - are you referring to aperture or AF performance? If you stick to Canon lenses then AF will be quicker and more accurate (in most cases) because the non OEM lenses have to be reverse engineered to work on Canon cameras. Other factors are bulk, weight and above all price! Assuming that you are not going too silly then I would suggest that you look at a used Canon 300 F2.8 L IS Mk1 + 1.1 Mk2 and 2 x Mk3 extenders. This lens is a bit hevier than your current one but not horrendously so and is simply about as good as it gets at 300mm. It is excellent with a Canon 1.4 Mk2/3 extender and surprisingly good with the Canon 2 x Mk3 extender in decent light. The downsides are the weight (2.6 Kilo) and the long (2.5 meter) minimum focus distance. You can get around the MFD a bit with extension tubes but you still can't get that close for the larger bugs.
Another lens to look at is the new Canon 100-400 L IS Mk2. I haven't used one but I am reading awfully nice things about it! Unfortunately at 400mm it is F5.6, like the 300 F2.8 + 2 x extender at 600mm so not the best for low light. Against this it is quite a bit smaller and has an excellent minimum focus distance of 98 cm - at 400mm that close it gives 0.31 magnification = more than enough for Dragonflies and Damsel flies will be far from small.
Just some food for thought!

John,
Very grateful for your detailed reply, Canon 100-400mm is the one for me i think..

falconer2406 said:

John,
Very grateful for your detailed reply, Canon 100-400mm is the one for me i think..

Click to expand...

Are you looking at the Mk1 or Mk2?
They are quite different lenses at very different prices!
The Mk1 is pretty good and quite cheap secondhand + it has the "Trombone" zoom which I like.
On the other hand the Mk2 has a twist zoom - which I (personally) am not so keen on. Against that is the fact that it is significantly better optically, has batter IS, and will focus much closer.
Another benefit of the Mk2 is that it works quite well with the 1.4 extender (the Mk1 is not so hot here) and will AF on a 1D3.
Overall, if you can stretch to it, the 100-400 Mk2 is an excellent option.