1D mk iv (1.3x) vrs 1DX (1:1) w 1.4 extender - whch is better?

[Richard Lane]

Wouldn't the bokeh be a result of FF shallower dof vs the crop, not necessarily the camera.

Yes, that, plus 700mm vs 650mm. That's why I choose f/7.1 on the 1DX, and f/6.3 on the MKIV on one of the sets of images.

I wonder how much better the 500mm will be with the 2x III. Maybe very usable.

So should I be trading up to the 1d x from my 1d IV?

I think the 2XIII will be even better.

That's a good question, based on my experiences so far, I would have to say that you can gain back the crop factor of the MKIV by using the 1.4XIII on the 1DX, and then have a better camera overall, that is full frame, focuses faster, has higher fps, and produces cleaner images and handles higher ISO's better.

Of course, you can't gain back the entire crop factor, but the trade-off seems worth it to me.

Edited: I think the other consideration is to get the 600mm vs 500mm which also adds quite a bit of cost.