Best 2X for Sigma 120-300 2.8 OS???

I'm thinking of buying the 120-300 2.8 OS for my 7D, but 600mm/ IA Servo capability/ & BIF IQ are a high priority for me.

I've seen what appear to be very good results with the Sigma 2.0X EX APO DG, & Canon 2Xii.

I'd be willing to "pony up" the "extra" $200.00 for the Canon 2Xiii for even a marginal improvement.

Has anyone done, or know of any direct comparisons with "this" lens, & these Converters?

Leigh

www.leighwax.com

I don't believe the Canon will work with the Sigma lens. I know the Canon 1.4x would not work with my Sigma 150-500, so I sold it and picked up a Kenko DG 300Pro 1.4x and it works fine with all my lenses. Any teleconverter will effect image quality quite a bit too, btw.

The Canon 2x mkIII works. No experience with others.
Sample image with 2XIII on a 7D at f5.6:
http://snapperz.smugmu​g.com …W#1485010300_57​hBrVz-A-LB
100% crop from above image SOOC:
http://snapperz.smugmu​g.com …Gx55Hk#14850064​09_PGx55Hk
Sharpened:
http://snapperz.smugmu​g.com …Gx55Hk#14850412​44_hG3ZhSZ
Although IQ with a 2X clearly isn't perfect there's significant extra detail compared to using a 1.4XIII and you can't get a much tougher test than the 7D's densely packed sensor. The os lens performs much better than it's predecessor with a 2x.

This was with a Sigma 2X on my 150-500

I have the Sigma 1.4 and 2.0 along with the 120-300 (Non-OS). The 120 went back to Sigma due to focus issues so I haven't been able to really work it with converters.

This is what I was able to achieve with the converters stacked on the Sigma 150-500