My reasons why with the most important reasons first:
A few observations, especially #5.
I do not use a 1Dx, but I can set custom shooting modes for action photography. I have “automatically save setting changes” for custom shooting modes disabled. I use C1 for One Shot AF mode, Single Shot drive mode, only the center AF point active with Spot AF focusing, BBF, and Manual shooting with Auto ISO. I think of this mode as “Bird Sitting on a Hidden Tree Branch” mode.
I use C2 for more conventional action photography, almost like a custom AF Case setting. This mode has AI Servo AF mode, Continuous Shooting drive mode, All AF points active, but beginning from the registered center AF point, no BBF but the button is set of [AF-OFF], and Manual shooting mode with Auto ISO. Depending on how long I tap the [AF-OFF], I can either pause tracking with a quick tap, or I can hold it just a beat longer, and force AF tracking to reset back to the center AF point to re-acquire a lost target.
There are a few common settings for both shooting modes. I have found Manual shooting with Auto ISO allows me prioritize both SS and Av, while allowing the camera’s excellent ISO range to do its’ thing. Of course, i set a maximum ISO setting that can be used when ISO is set to Auto.
In both custom modes, I have programmed the [SET] button to allow me dial in AEC when shooting in Manual with Auto ISO, because the metering system can easily be fooled when shooting a BIF against a sky background compared to when a background of trees and foliage.
Hope this helps.
My reasons why with the most important reasons first:
- The focus system is probably the best focus system on any camera. It will lock onto a subject and follow that subject. I tried this by locking onto a gymnast who entered a group of about 20 other gymnasts and weaved through them. The camera followed focus on the subject throughout. I believe this is the only focus system that will follow based on color.
- The camera lets me shoot at high ISO speeds. I'm still playing with noise reduction and some of my software hasn't been upgraded to support the camera, e.g., DxO Optics, but I wouldn't have any qualms about shooting at 12,800 and getting results as good or better than my 5D MkII shooting at 3,200. The two full stops mean the difference between trying to shoot action in a dark gym at 1/250 sec (blur) versus 1/1000 sec (crisp).
- The camera is a full-frame camera so my big aperture-prime lens investment is protected.
- The camera is capable of taking 12 frames per second in normal operation (14 if the mirror is locked-up but that has limited application). Combine this with the ability to follow focus and actually focus-lock on faces and I know I'll get more dead-on action shots.
- The camera ergonomically designed and highly configurable. There are fully redundant controls for portrait and landscape mode. You can configure nearly any button on the camera to do what you want. The two I've set for now are the depth of preview button and a nearby multi-function button. I've set one to immediately switch between AI Focus and On-Shot focus modes and the other to go immediately to a registered AF Point (different points for portrait and landscape shooting). So, less than a second to switch from one mode to another. So, for example, I can start an action sequence focusing on a sbject offset to the left and then switch to using all AF Points while shooting.
- You can save multiple camera configurations. My current configuration is for indoor sports. I've saved that as shooting mode C1. I'll likely configure another setup for portrait photography and save that as mode C2. My third setting will likely be for landscape photography and that will be C3. The way I use the camera for each setting is different so my configurations will be different. Rather than go through all the set-ups where I might need to change a dozen items I can just recall them. I realize that saving shooting modes is nothing new but this is extensive since it ties to the camera configuration capabilities.
Virtually all of the features that you cite can be found on other Canon DSLRs for considerably less money. What makes cameras of the "1D" series stand out is their rugged construction. They are intended primarily for professional (or very serious amateur) photographers whose cameras have to perform reliably despite heavy usage under challenging conditions. If that's your situation, then you have every right to feel that you're getting your money's worth.
"What makes cameras of the "1D" series stand out is their rugged construction." "... cameras have to perform reliably despite heavy usage under challenging conditions."
Bingo! One other small segement of hte market is 'bling'. SOme folks just need the most expensive whatever no matter whatever.
I use a 1DX and 1DX II primarily for the high frame rate and ability to withstand any environmental conditions in which I am willing to shoot (and the camera would probably be fine in worse conditions than I will tolerate).
You can get higher resolution and less weight for less money.
And no matter which body you buy, the glass is still the most important link in the chain. A so so body with great glass will provide far better images than a 1DX II constrained by mediocre glass.
And even though the current crop of DSLR bodies is very smart, they can't approach their capability without a knowledgeable and engaged user.