I agree, a lens shade will always improve saturation and contrast, as well as cut flare, which is the Devil in all this.
I really think the stock shade for the 17-35mm does not take into account the 1.5 CCD crop. It is so wide It really does little when shooting into a spectral light source.
I recently bought a Nikon 72mm polarizer and HN-29 shade for the 17-35mm and now that thing really WORKS, though it vignettes up to 24mm, since I have found that about 28mm to 35mm is the best focal length for stitched panoramas, it is cool for those and really keeps out the stray light.
We need 1.5 CCD crop sized shades now!
Cheers,
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Pernel Pixel is Pure Digital Now
D-1 - D100 - 45mm f2.8P - 60mm f2.8 - 17-35mm f.2.8 - Oly C5050z (new pocket pal)
Past Life: lost TWO Nikon SP's !@^@! - F's - Ftn's - Nikormat EL