what sort of response is that? I know its late, but thats a bit...well...weird.
I have discovered why alot of my shots have a yellow/grey over tint to them.Its a sigma lens thing. Just something the lenses are common at casting a very slight, almost an ND warming filter, tint to them.
well if you make the sound it sounds like someone agreeing....
well the greyness has nothing to do with the lens, the tint might. The greyness is an exposure error (underexposure), nothing more. The cameras metering system sees thorought he lens so it would compensate for any very fractional darkness in the glass. Some lenses do flare (as you know) so that could result in a lack of contrast but that would be more of a white overlay for a correctly exposed file.