I can't believe I've been so dense. It was right under my nose all the time. The one critical set of capabilities that makes the fz2500/2000 such an incredible bargain for video shooters hellbent on getting maximum quality at a low price point. It's all about the clean HDMI out.
Let me explain. The Sony a7x's and RX10's are great cameras for shooting video if you are intent on using them only to capture video to internal SD cards. Just like the fz2500 they write really nice (albeit compressed) files directly to internal cards but in order to do so they limit the color information to 4:2:0 and the they limit the bit depth to 8 bits. Within these constraints they do a very good job. But the differences emerge when one hooks up an external field recorder and sends a pre-compressed signal out the HDMI connection to a waiting SSD drive. The fastest SD cards can sustain a write time of a little over 120 mbs but if you want higher bit depths and richer color spaces you'll need sustained write times closer to 200 mbs. And that's exactly what field recorders give you.
But, if you hook up an Atomos (or other brand) field recorder to one of the Sony cameras you gain only greater bit depth and not a change from 4:2:0 to 4:2:2 color information. With the Panasonic fz2500 you gain 10 bit, 4:2:2 color even at UHD video, at 24 fps and 30 fps. This is crazy good. And the field recorders allow you to take the clean HDMI signal and write ProRes files to the SSD card which means there's no need to transcode when ingesting the files into your editing program.
What does the change from 8 bit to 10 bit buy you? Better tonal separation and less banding in uniform color areas within a frame. That means less banding in blue skies and more realistic tonal shifts within a frame.
What does the change from 4:2:0 to 4:2:2 buy you? You are getting more color samples to work with which gives you more color accuracy and richer color in your files. It means the files are easier to work with and edit because there is more information to work with. It's a big step up.
I was really busy doing projects when I bought the Panasonic and I'm sure I must have read about this capability somewhere but... when you have your head down in projects you are loathe to change directions or workflow because the unknown or untried is...scary. Now I am paying attention and I'm delighted to investigate just how big a change the use of an external recorder will be for my video work.
I'm trying to decide which recorder will work best for the fz2500 so if you have any information, experience or opinions I would love to hear them. Right now the Atomos Ninja Fire seems to be the right choice but I'll wait to hear from some of my smart readers.
Realizing the potential I have sitting in this camera in front of me on my desk is like unwrapping an new present. Now to acquire the external recorder and start testing.
Video really is a deep dark rabbit hole. Bring a flash light.
Hey! Sony! Unlock 10bit in the RX10iii and I'll put you on my Christmas card list...