Starting a thread dedicated to tips/tricks/settings that are only possible on the 1D X.

I'll start...

The 1-series cameras can save the current camera settings to a card, up to 10 sets, and load them on demand. The 1D X is the first 1-series body to feature Camera User Settings (C#). The combination makes for a powerful way to manage groups of settings, since the three C# settings are saved and loaded along with other settings.

For example, I have an Outdoors set, where C1 is for landscapes on a tripod with MLU, etc., C2 for static birds/wildlife, and C3 for BIF. I've got a People set, C1 for tripod shots with me in them (10 s timer), C2 for static shooting (min 1/125 s, manual AF point selection), C3 for moving kids (1/250 s min shutter, 61-pt AI Servo). I also have sets for Sports, a set with settings most useful for shooting birds with a supertele lens (higher minimum shutter speed, etc), and another set for manual AFMA with the FoCal settings.

I store them all on a few old, smaller CF cards carried in the pocket of my Blackrapid RS-4 strap and commonly used camera bags, with a backup of the settings files (.CSD) on my computer.

To make it easy/fast to switch between C# modes, I assigned mode switching to the M.Fn button next to the shutter release. Pressing that cycles through the C# modes (in order) and the last-selected non-C mode. I also use the ability to restrict the available modes - for example, in the Outdoors and People sets, I have the C1 setting disabled, since those shots are on a tripod, meaning I have the luxury of time. So, I can be on C2 and if action starts, I'm one press of the M.Fn button away from the C3 action settings (and two presses back to C2).

I find this setup really facilitates having the camera settings where I need them, when I need them.