RWY-16 From Switzerland, joined Dec 2000, 106 posts, RR: 3 Posted (13 years 7 months 3 weeks 6 days 6 hours ago) and read 2105 times:
My zoom lens 70-200/2.8 shows some vignetting with an aperture f 5.6. If I use a teleconverter, for example the x 2.0, how strong is the vignetting with the same aperture f 5.6? Is it the same or is it more or less?
Ckw From UK - England, joined Aug 2010, 785 posts, RR: 15
Reply 1, posted (13 years 7 months 3 weeks 6 days 6 hours ago) and read 2087 times:
I'm surprised at a 2.8 vignetting at f5.6 (two stops down!) normally vignetting is most apparent wide open and reduces on stopping down. If what you've stated is in fact the case, I'd consider getting the lens checked - what is the vignetting like at f4 or f8?
To answer you question, it is not unusual to find some vignetting with a teleconvertor, esp. with the lens wide open. Stopping down one or two stops usually avoids this, but in the case of your lens its hard to say.
Jwenting From Netherlands, joined Apr 2001, 10213 posts, RR: 17
Reply 2, posted (13 years 7 months 3 weeks 6 days 5 hours ago) and read 2080 times:
Is it really the lens or the scanner?
My scanner sometimes causes what looks like vignetting in the corners, even when scanning only part of the image. This is most visible when the center is bright white, leading me to believe it has to do with the exposure settings of the scanner.
Da fwog From United Kingdom, joined Aug 1999, 867 posts, RR: 8
Reply 3, posted (13 years 7 months 3 weeks 4 days 7 hours ago) and read 2048 times:
I'd like to know what lens that is. I have the Sigma 70-200 F2.8EX & matched 2X converter, and my experience is that vignetting is negligible at ALL apertures with the lens on its own, and only really apparent wide-open at F5.6 using the converter.