Okay, so I find a Pringles-type lid and use Preset WB on the D70 kit lens. I do some shooting at dusk. What a difference! I am thinking that perhaps now I know how to take pictures! Today I put the 70-300ED lens on and do the same thing. This time I am zoomed out to 300mm. My factory WB settings look closer than the Preset option! The differences were that the subject was in bright sunlight and I was in the shade and the focal length. Is the fact that I was in the shade make this much difference? If so, does the Expodisk work any differently? Does anyone have any suggestions (aside from post processing)? Thanks.