I am looking at this lens “Canon Zoom Wide Angle-Telephoto EF 28-300mm f/3.5-5.6L IS USM Autofocus Lens” as seen here (http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=319784&is=USA&addedTroughType=categoryNavigation)

I am curious how good the optics are. I would like to attach it to a Canon EOS-1DS mark II

Any input would be appreciated.

You can find test reviews of that lens at: http://photozone.de, click on the reviews tab at the top of the screen, and also http://www.fredmiranda.com, again click on the reviews tab at the top. It seems to be a good one.