Lens Quandary

Having sold my 300/2.8 (which I used with tc’s for bird) solely for weight reasons the longest lens I now have is the 70-200/4 non IS (plus 1.4x tc).

I was looking to get a 70-200/2.8 IS mkII plus a 2x tc mkIII for the occasional bird shot but have now started thinking about maybe upgrading to the 70-200/4 IS version and also getting a 400/5.6 prime for the birds.

So my options are:
1) 70-200/2.8 IS MkII plus 2x tc MkIII
OR
2) 70-200/4 IS plus 400/5.6 (sorry not interested in the 100-400)

Is there a lot of difference in IQ between the 70-200/2.8 IS MkII and the 70-200/4 IS. Which route would you suggest. BTW I shoot with a 7D

Thanks for any help

If F/2.8 is your priority then I suggest option 1. But if F/4 (or bird shots) are more important then I suggestion option 2.

Roy as someone who enjoys bird shots and who has a 70-200 2.8 II, I can say that you are better off with a 400 5.6 prime. I use a 2X EF II on the 70-200 2.8 II and it works well, but I haven't got any BIF's with it, just stationary which we know isn't the same. I long for a 400 5.6 of my own, but really want a 500 4. I just can't justify the price. I will continue to rent the 500 4 but I might pick up a 400 5.6 eventually unless something cooler comes by.

i'd go with the 400 5.6 and 70-200 f4.

Roy,
Why not the 1-4 specifically ? Surely you can do away with the cost of purchasing 2 lens, and, having to swap lens in the field too A good copy of the zoom will be a one stop shop, plus you'll have IS at 400mm, and thats not to be under estimated.....

h14nha wrote in post #12709513
Roy,
Why not the 1-4 specifically ? Surely you can do away with the cost of purchasing 2 lens, and, having to swap lens in the field too A good copy of the zoom will be a one stop shop, plus you'll have IS at 400mm, and thats not to be under estimated.....

Thanks Ian but I do not want this to turn into another lens battle which is why I specifically gave the two options only. I have plenty of reason why I would prefer the 400/5.6 over the 1-4 for birds and also a 70-200 over the 1-4 for landscapes and general lightweight walk about stuff. The 1-4 is obviously a fine lens and the best of luck to anyone who has one but it is not for me.
BTW I have tried the 1-4 and the 400/5.6 previously.
I do know all about I.S. having had the Canon 300/2.8 I.S. and just recently I bought another lens with a 4 stop I.S.