Ian, when I was working hard at trying lenses out I found that apparent differences between pairs of lenses in color saturation usually (note, usually does not mean always) went away when I used the same shutter for both sets of cells. Since most of my lenses cover formats much larger than 2x3, I ended up hanging longer lenses in front of a Nikon (with aperture priority autoexposure, and I let it set the shutter speed) for testing central sharpness. With the same shutter running at the same speed most of the lenses I tried out differed not at all in color saturation. The Konica Hexanon GRIIs I mentioned were the biggest exceptions.
Originally Posted by Ian Grant
I use a Calumet shutter tester. I check my leaf shutters at least annually. Few are absolutely consistent shot-to-shot, Compounds consistently run fast at low speeds, slow at high, Compurs, Copals, Prontors, Rapaxes and Supermatics tend to be close to spec at low speeds, slow to very slow at high. No two run exactly the same.
To change the subject slightly, I've read claims that not all lenses render colors the same. I've encountered the effect when shooting in daylight -- on first trial some lenses have shot very blue -- but it hasn't been reproducible and I've never seen it when shooting with flash (always the same flash). It turns out that my blue shots were taken while the sun was behind a cloud. This raises color temperature ... I have somewhere a really nice shot, taken on an E6 emulsion, of an electric blue alligator. The 'gator was in deep shade. Same effect.
When I try lenses out I control everything controllable as well as I can. This may be why my results differ from many other peoples' assertions.