Chris,
See attached EXIF data for original jpeg image as requested.
FYI subject - my neice is the Bride with my grandaughter Eloise - whose silver broach you can easily read in the original image.
I quickly descovered that jumping to 15 megapixels and Digic 4, demands fast quality glass.
Also in case you don't know it, this website is IMHO the best professional review site for Canon equipment - see review of EFS 17-55mm:
http://www.the-digital-picture.com/R...ns-Review.aspx
You may have read whines about dust behind the front element, (no probs here, just keep it capped & in a lens bag). This lens is attached 90% on the 50D and stowed in my Lowepro bag. Note dust enters behind the zoom ring, as this lens does not have full enviro sealing as do "L" series lens. House keeping as for EPs.
FWIW the OEM front cap can be a PITA and should be replaced with a Nikon center pinch type - also works with the lens hood fitted
Other high spec Canon lenses that may interest you are 70-300 f4 - 5.6 IS (soft above 250) and 70-200 f4 L non IS (heavier but great value).
Although info not all related to AP, lenses should be fine for wide field and its in line with your thread.
PM me for more.
Cheers,
David