Teleconverter

Hi guys, just wondering does the Teleconverter brand really make a big difference.

Does image quality change if we use a CANON TELECONVERTER agains a KENKO?

I was thinking of using it for my 100-400 IS lens, is it recommended?

Here is the Link of the MC7=KENKO and MC4=KENKO lens converter (extender), they have 2 types of 2x though, what is the difference, as for the price there is a big difference, does anyone know why? They are both DG types (i guess stands for Digital), i guess they are versions, I suppose MC7 is the newer one? Does anyone here have either of them, how do they perform?

I hope to get more insights on this one. I know that there will be 2/fstops added when we use this lil babies, but this doesnt really matter if we shoot wildlife and sunny outdoors.

Insights on these very well appreciated. Thanks

The MC7 uses 7 lens elements, and provides a more highly-corrected converter (less degradation of the image) than the 4-element MC-4. But 2x teleconverters, regardless of the quality, will give you noticeably worse images than unconverted. It's almost better to get a 1.4x and crop/resize (the 1.4x TCs don'd degrade images anything like as much).