I know I sort of quickly replied on FB .. as you kindly tagged me there
Been a busy weekend with games and moving... etc...
You mentioned 'Soccerdome' ... would that be the one in Manchester... if so, I know exactly how 'good' the light is there, so no wonder you need to push the ISO!!
For me - I made the upgrade from 1DX to 1DX mkII (lucky to get one on the first UK release date) - and have been more than satisfied with the decision.
To my eye - there is improvement in the way the newer model handles the high ISO - as you should expect.
Less noise and the colours are more 'true/vibrant' when you start to move to the higher ISO numbers... compared to the 1DX.
Is it worth the extra £££'s you will spend on the 1DX mkII - for me, the answer is yes.
But it is not just the performance on the High ISO that sold the upgrade to me...
The AF is slightly better (not sure why it is always only 'slightly' better with each upgrade...) - the AF on the touch screen (for my video work) - the ability to grab a good quality JPEG from the video footage...
Just few of the reasons I used to justify the jump from 1DX to 1DX mkII (although - the 1DX has still stayed as my remote camera for basketball!!).
Another good, or bad, thing is the new memory card... the CF Fast is much faster than your CF card.. and on a busy basketball game.. it does make a difference on how quick I can empty my card.
I know.. a little thing... but it all helps
A downside of this is that now I am using both CFfast and CF cards.. so carrying two memory card readers with me...
I can see if I can find some good and bad samples that I've shot at 25600 ... and post them here for you to see.
If I were now in a position to consider again whether to upgrade.. and knowing what I now know from using the camera for the last half a year.. would I still upgrade???
Yes, definitely!!