Having a man’s “above normal” size hand, the handling of the 5D vs. the 1Ds is a big difference. The weight of the 1Ds is about double the weight of the 5D, but I usually have heavy lenses on it so personally some 750 additional grams difference does not matter. To anyone who hasn’t tried a 1D body, this may sound just like an old die-hard masochist trying to justify obsolete stuff, but believe me - it could not be more wrong. Owning both, I hope that you believe me ;-)

To me, the 5D feels “cut off” and it seems to be designed for someone with just four fingers. Especially when hand-holding it with a heavy and/or long lens, the feeling is that nothing really gives a counter-weight to the lens itself. My walk-around lenses are the 70-200/2.8L IS and the 24-70/2.8L, and they feel somewhat oversized for the 5D.

An option could be to get a vertical grip for the 5D and I’ll think about it. I shoot a fair amount of portraits, so redundant controls for vertical operation is really great (and an orientation sensor that the 5D has!)

Comparing the display of the 5D with the 1Ds is like comparing a new 32” flatscreen TFT with an old IBM XT CRT monitor. The 1Ds screen is completely unusable in strong light and has so small resolution that it is almost a challenge to check the histogram. The gamma and color rendering on the screen is crap compared to the large 2.5” 5D screen. But, personally I think a good screen is a "nice to have" and is no decision making point per se.

The 1D-series controls are fundamentally different from the other Canon bodies, like the 5D. Apart from the difference with the dial on the 5D and the buttons on the 1Ds, the main difference to get used to is the requirement to “push-and-dial” on the 1D-series.

Personally, I cannot really say I’m for the one or the other but it’s a bit frustrating to switch between them. I’ve learned to appreciate that controls don’t accidentally slip, but sometimes you’ve only got one hand left. I really cannot understand why Canon does not make this selectable via a custom function to be consistent over the entire range. Default can be A on the 1D bodies and B on the others or whatever. It must be a simple thing to implement really.

As a closing word, the exceptional feeling of quality and robustness of the 1D bodies is really something. The feeling of a solid block that was milled into its final shape really attracts me and makes the machine a joy to use. It goes without saying that it is heavy, but weather sealing and robustness has its price. Just a simple detail like opening and closing the CF door on the 5D really makes you afraid that it will fall off if you sneeze. But – let’s be fair. Compared with other “normal” DSLRs, the 5D is probably “above average” in this respect.
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