What version of Photoshop are you running? The latest version is version 26, also called "Photoshop 25." The oldest version to open R6 Mark II files is Photoshop 24.
Let me take a wild guess. The OP has CS6. The last time it has an update was in 2018.
But I guess we will never know. The OP pops up to whine then disappears.....
Hi,
I then went to bed then had breakfast then tried to get metashape to process some test shots, failing badly on skin areas, then maths to see I need 17 batteries for a photoshoot with this R6 THING...as 400 pics per battery is BAD. no youtube review mentioned you need loads of them compared to 1 for a dSLR such as a 70D. (there again youtube reviews often useless, are not always mentioning everything one needs to know. )
I am wondering why on earth you decided to rent a completely foreign camera (to you) with a very limited amount of time to learn how to use it, and clearly without much research before renting ? A VERY common theme in this R forum is how big the learning curve to move from DSLR to mirrorless is - in most cases it is NOT a 5 day exercise, and it seemingly (as expected) causing a lot of stress for you. Why didn't you stick with your 70D for this shoot, or even rent a DSLR "upgrade" like 5D iv - it may have been easier for you.
For the record, you should completely ignore the CIPA test spec for this camera - unless you are going to be fluffing around and examining each shot at length after taking it.
So you are planning 6800 shots, which I might assume may include some bursts (simply because taking 6800 single shots of different subjects is likely to be a fairly time consuming exercise). If taking lots of short bursts and mostly not reviewing the shots on the camera's LCD, I might suggest that you are more likely to get around 1500-2000 shots per battery, not 400.
I have a little R8, which takes the much smaller LP-E17 battery, and it is "rated" for around 250 shots, and walking around a big zoo for 6 hours, I took about 4500 shots, and was on my second battery - and yes, there was some decent bursts in that and very little reviewing going on.
So, no, it seems unlikely that you will need 17 batteries.