Sigma 2 X T.C. and 150-500
Tom Kelley wrote:
Has anyone ever tried this combo? I know this lens is 6.3 at 500, and will only be MF, so what can i expect as far as quality? Does anyone have any samples?
No, but I can't imagine it producing very good images for several reasons.
1. I've never used a 2x, and I've tried several, that didn't noticeably degrade IQ, unlike 1.4s which are not terrible. I've never personally used a 1.7.
2. I'm assuming you are going to be shooting at the very long end of this lens, otherwise, there'd be no point in using a 2x, and beyond 400mm on that lens you need to stop down to f11 to get decent sharpness even in the center of the frame. This would yield f22 exposure with the 2x on, meaning shutter speeds acceptable at that focal length would be impossible with anything but the best of tripods and stillest of subjects.
3. MF only means still subjects, so the likelihood of always getting consistently well focused shots is unlikely with anything like wildlife or birds.
If you have the lens already, I'd just stick to cropping images. I suspect the lost pixels would be more than wiped out by the lost quality of pixels with the 2x on. If not, I'd consider the new 150-600 VC Tamron to get a little extra reach and a lens that by early reports might be sharper than the big Sigma zoom wide open, you might could get away with a 1.4x on it and still focus on newer bodies.