Kelly Frame
04-10-2008, 08:39 AM
As I haven't bit the bullet and bought a 600 mm lens yet, I occasionally use a Nikon TC-20E II teleconverter on my 200-400 VR f/4 lens. I realize that per Nikon's recommendations this combination should not work properly with autofocus, although I have found that it does seem to work OK with reasonable light.
My question concerns the sharpness of the photos taken, which leave a little to be desired, relative to photos taken with the same lens, but without the teleconverter. Is a degradation in sharpness to be expected with any teleconverter or is it a reflection of autofocus issues using this particular teleconverter (i.e., although the lens appears to lock in a focus, perhaps it's slightly off)? If I were to go to a TC-14E II teleconverter, should I expect sharpness similar to that of just the lens itself?
Any thoughts would be appreciated.
My question concerns the sharpness of the photos taken, which leave a little to be desired, relative to photos taken with the same lens, but without the teleconverter. Is a degradation in sharpness to be expected with any teleconverter or is it a reflection of autofocus issues using this particular teleconverter (i.e., although the lens appears to lock in a focus, perhaps it's slightly off)? If I were to go to a TC-14E II teleconverter, should I expect sharpness similar to that of just the lens itself?
Any thoughts would be appreciated.