Top critical review
14 people found this helpful
Does what it says. Limited lens compatibility. Manual Focus only for many.
on June 13, 2012
First off, if you are considering a teleconverter, you are doing so to extend the focal length or reach of a telephoto lens. NOTHING ELSE. This does not help macros or do much for most mid- or wide-angle zooms.
Second, before you even THINK of buying....GO TO THE MANUFACTURER'S WEBSITE AND CHECK THEIR COMPATIBILITY TABLES. For YOUR mount. For YOUR lenses which you'd like to use it for. THEN decide if it's worth the price.
Many of the other reviews here are complaining that it isn't compatible or doesn't work or won't allow autofocus...when an educated buyer would have found that out ahead of time. If the compatibility table says it will work but it doesn't...THEN complain.
That said, I still only give it 3 stars because even knowing all that, I am finding the usefulness is more limited than I thought. I'm using on a Sony A55, with a Sigma 150-500mm lens. On that lens this teleconverter works in manual focus only (which I knew), and the 1.4x TC costs you a stop of light (which I also knew). What I didn't really realize was exactly how bloody hard it can be to manual focus at an effective (35mm equivalent) 980mm focal length and a max aperture of 7. The lens to which it is attached is a 'focus by wire' so even trying to very softly feather the focus while shooting multiple frames on a tripod, it's pretty difficult to get the focal plane right where you want it, and you'll be shooting pretty high ISO to get the exposures down to where motion blur isn't also a problem (the lens has optical stabilization, but the TC multiplication factor does reduce the OS's ability to give your a couple stops of stability improvement) unless you're shooting on from a very stable platform (tripod), at a very still subject (e.g. birds on moving trees in the wind is an issue), or on very very sunny days.
It does what it says it should, so in that regard I have no real complaints. But I didn't really expect it to feel *this* limited at the long end, which is the primary purpose for which I bought it, so for the price the advantages seem kind of thin now.