I have to agree with the conclusion of this photo.net article. Teleconverters are handy but it’s very difficult to get usable, good quality images from them.
I use a third party 2x TC on my Sony F717 from time to time, and there’s visible degradation of image quality. The article above recommends using a powerful lens and at most a 1.4x TC so I’m seeing the most dramatic distortion. It does help if I set the EV down one stop but that’s not always an option, especially in cloudy and overcast Ireland!
