Some test results of tethered shooting with the 1DsIII including some comparisons with the 1DsII. The IDsII has the edge on speed because of its firewire interface. The test mostly focuses on the 1DsIII however.
These timings are with the EOS Utility preferences set so that there is no linked software. There was no memory card in the camera for these tests. EOS Utility v2.3 on Mac OSX, version 2.2 on Windows XP and on the G4. Cameras Manual Focused.
All timings are approximate and used the 'wet finger in the air method' for recording times. I was most interested in the relative speed of different methods.
1) MacOSX Leopard, MBP 2.3GHz, Tethered Shooting, RAW, 10 seconds.
2) MacOSX Leopard, MBP 2.3GHz, Remote Live View, RAW, 30 seconds.
3) MacOSX Leopard, MBP 2.3GHz, Tethered Shooting, L JPG, 5-6 seconds.
4) MacOSX Leopard, MBP 2.3GHz, Remote Live View, L JPG, 13 seconds.
5) WinXP Bootcamp, MBP 2.3GHz, Tethered Shooting, RAW, 5 seconds.
6) WinXP Bootcamp, MBP 2.3GHz, Remote Live View, RAW, 13-15 seconds.
7) WinXP Bootcamp, MBP 2.3GHz, Tethered Shooting, L JPG, 1-2 seconds.
WinXP Bootcamp, MBP 2.3GHz, Remote Live View, LJPG, 5-6 seconds.
9) MacOSX Leopard, G4 MB 12", Tethered Shooting, RAW, 30 seconds.
But more significantly.
A 10 frame RAW burst in tethered mode
10) MacOSX Leopard, MBP 2.3GHz, 1Ds II - 10 seconds
11) MacOSX Leopard, MBP 2.3GHz, 1Ds III High Speed Burst - 60 seconds
12) WinXP Bootcamp, MBP 2.3GHz, 1DsIII High Speed Burst - 15 seconds
I conclude from this that shooters of fashion might prefer to stick with the 1DsII if the file size is OK (which it probably is for many purposes), particularly if they rely on a Mac.
Disclaimer : this test is offered without warranty, was done for my own edification and is shared purely for reasons of community spirit.
I should say... if my tests are wrong, I'd like to know! Thats the right scientific spirit!