the latest ones seem pretty good, better than the Kenko or Tamron ones in Pentax mount anyway. they will work on MF lenses as they support AF by having a passthrough for the drive shaft used by Pentax AF lenses. as pointed out elsewhere, the frontmost element is very far forward and can interfere with some lenses' rear elements. i had the 1.4X and 2X and neither of them would work on my FA* 80-200/2.8.
Herb... ----- Original Message ----- From: "Andre Langevin" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Monday, October 11, 2004 11:26 AM Subject: Sigma AF 1.4X worth considering? > Good optics? Is it also compatible with MF lenses?
