I don't know about the Kenko, but I bought the digital concepts 2x teleconverter . $65 on ebay. Received it today. I only tried it very briefly to make sure it worked. With my Tamron 28-300 (f3.5 - 6.3) I can still use autofocus even at the highest zoom apparently.
I have only taken a couple of test shots indoor that didn't turn out very good . There was noticeable blur on the pics taken at 600mm (300x2) vs 300mm with the lens alone, even at 1/180 with the built-in flash. This could well be due to autofocus just getting it wrong with the TC. No doubt I will experiment some more and with other lenses and manual focus.
I wanted the TC mostly for sky shots, in particular to get the moon to fill the frame - 300mm was still too small for my taste. If it can get me more detail on the surface of the moon, then I will be happy with the amount I spent.
Originally posted by cupic With the scare resource of Tamron 1.4 super TC (hard to find) this has lead me to but the Kenko 1.5x DG AF TeleConverter.
Is it as good as the Tamron Legend(I think not)
Do you still have AF infinity,or more to the point is there anything lost
Any one has examples of this TC in action
cheers