Canon 70D, 70-300L and Kenko Telepro 300 1.4x?
Has anyone tried this combination using the live-view function of the 70D? Theoretically, it should autofocus, as the 70D is supposed to autofocus down to f/11. And, how about the Kenko 2x converter?
I bought the Kenko 1.4x Telepro 300 and tried it with my 70-300L and 70D. Here is what I found:
Image quality - pretty good even at 300mm (420mm). But when I cropped a 300mm shot without the converter to match the image size of the same subject with the converter, the image quality was nearly identical.
Autofocus - erratic but usually OK, but needed a high-contrast subject even in daylight. In bright room light the lens still autofocused given a high contrast subject. (I can make the same statement about the lens without the teleconverter.)
Image Stabilization - worked well. One of my indoor shots was at 1/4 second and reasonably good, although not perfect.
Live View - did not help autofocus much. I find that autofocus is slow in this mode, even without the teleconverter and with all of my lenses.
EXIF Image Information - accurately reported - aperture showed as f/8, the actual effective aperture at 300mm using the teleconverter.
My Overall Conclusion - Although the converter worked better than I expected, I decided not to keep it. As I could get the same image quality without the teleconverter by cropping the image, I could not see the value.