Best Converter for 70-200 2.8II?

I need more reach with my 70-200 2.8II, but have no knowledge of converters because I had a 300mm for the reach. I just wanted to ask which converter, from any brand, is the best "bang for your buck", and which one produces the best results. Hopefully it can be both, but I will settle for results over price. It could be 1.4 or 2x, but I just need something with more reach. Thanks!

Since your gear list reflects the 5D MKII i would suggest the new Canon 2X III version. This combo can produce images equal to the bare 100-400L at 400mm/f5.6 - f8.0

Best bang for your buck on a crop body sensor is the Kenko 1.4 Pro300 DGX, Kenko 1.4 MC4 DGX, & the Kenko 2x MC4 DGX providing you dont need weather sealing.

http://www.traumfliege​r.de …elekonverter/ov​erview.php

Regards whatever your decision,

Recently traded my Canon 2x Mk2 to get a Mk3. I read there is no real difference between the 1.4 Mk2 & 3. I can confirm, however, that with the 2x extenders the Mk3 is better (I think its significantly better) but it is an awful lot of pennies!

johnf3f wrote in post #12820664
Recently traded my Canon 2x Mk2 to get a Mk3. I read there is no real difference between the 1.4 Mk2 & 3. I can confirm, however, that with the 2x extenders the Mk3 is better (I think its significantly better) but it is an awful lot of pennies!

The 1.4x III is very slightly better in the center and noticeably better at the edges (far less CA, but even once you correct for that it still has better micro-contrast at the edges for sure).

Never tried the 2x II but the 2x III on a 300 2.8 definitely does better than upscaling 300 2.8 + 1.4x TC III.

It would be worth while getting the 2X III and trying it out. I was amazed at the IQ on the 70-200 II.

I have been debating this very question for some time. I am just saving up for the new Canon 2x III.

Should have mentioned this in my first post!
I have tried the 2x Mk3 on my 70-200 F2.8 IS (Mk1), 300 F4 IS and 600 F4 IS and, though I cannot compare directly, I am certainly getting a better "Hit Rate" and the IQ is about the same as using my 1.4 Mk2 extender - in other words better than the 2x Mk2, which though good was noticeably poorer than the 1.4. Very non scientific, but the bottom line is that the 2xMk3 extender is always in my pack, the Mk2 wasn't - nuff said.