Thanks for rescuing me bubffm - for a while there I was just talking to myself.
Yes its quite the dilemma now. Sigma Fp or BMPCC6K. Pros's and cons each way.
The FP is REAL RAW and uncompressed at that - high data rates for sure so there's that to consider but the goodness of cDNG uncompressed is hard to overlook. Compared to BRAW which is not a "REAL" RAW at all (12bit YUV with a log gamma curve).
FP is 4K at 24p - maybe a firmware update will bring 25p - it seems likely from all the reading I have done on it. It does do 60p at 1080p 12 Bit RAW though, so if 60p is a deal breaker you can still have it albeit at lower res. Still, its not 4K 60p, is it. So there's that.
BMPCC6K goes up to 6K which is great for cropping and destabilizing then use what is left to down res to 4K - that 4K is going to shine and we get 50p at 6K BRAW.
Those in the know claim the Sigma colour science is better then the BM colour science. Kinda makes sense given Sigma's Foveon cameras of the past. They understand colour science so it figures this carries over to the FP. But BMD keeps getting better and better at this.
The under exposure recovery of the Sigma FP is nothing short of AMAZING. Highlight recovery not so much. Depends on where you dive I guess. Being to pull up the shadows in post is something more important than recovering blown highlights I think. Not too many highlights down there at depth to blow.
The Sigma FP is totally usable at 6400 ISO no bother at all. Completely normal footage. WOW! Its still OK at 12800 ISO. Gets a little noise at 25600 ISO that can be cleaned up nicely in post.
The BMDCC 6K you dont want to push past about 1600 ISO - which is still incredible compared to just a few short years ago, but its not 6400 ISO.
The Sigma FP is tiny and is having a tiny housing made for it - so far the specs of the housing are 142mm x 109mm x 70mm !! While it does not apply to me, it has got to be useful in a strong current to have a tiny housing setup with you to push through the current.
With the FP you are recording 24 x 12.7 MB 12 Bit RAW still frames per second - that's 2400 Mbps ! M.2 SSD's to the rescue thank God. This new housing still on the drawing board will house an M.2 NVMe SSD - and they go up to 2TB. So its all doable.
I was set on the BMD CC6K. Now - not so sure. Both have under water contact optics - I would say the Naughty Cam has an advantage here as with the new WACP 2 you can do under/over's and of course can zoom through a useful range all from one lens. But then again the Nikonos 15mm is a legend among legends. So ...I dont know.......