Cause it has Full Frame, Fast autofocus, slow mo, Integrated Nd, very good DR , lowlight capabilities, sdi, hdmi, XLR and lightweight body.

Markr041, because:

1- A7S III has IBIS that can’t be used during action sequence or on a suction car mount. Try, you will understand what’s IBIS vibrations means. FX6 is perfect without IBIS.

2- A7S III don’t have built in ND. And FX6 has a very special electronic ND that can operate smoothly. I seen it in action, very impressive.

3- form factor is very important.

I myself would much rather have two A7s iii than one box of buttons.

No, the fx6’s ND is a VERY different from old FS5.

You don’t need expensive suction mount, you just need to know where is high frequency and low frequency vibrations on a car...

If you worked with DOP on important productions you would know that having a camera combining image and sound in a wireless block is the prerequisite to avoid problems and errors in assembly and disassembly. On an HBO, Netflix, Warner, BBC shoot, everything has to go very quickly, you don't have to think to solve rig problems but to think to be creative.

Faster and faster, this is how I work on high end production...year after year. It’s the reality of this industry.

I agree with @flash, on a professional set, there is not extra time and always something/someone needing your attention.

Then there's the argument about the IQ from better cooling.... https://robomartion.medium.com/why-the-a7s-iii-and-canon-r5-are-not-for-cinema-cd8496374c6f

I like the FS5 form factor, buttons are good when you are in hurry! I personally prefer APS-C (will we see a FS-6?) and on the FX6 I don't see any mic input options when the handle is removed -for when you're on a gimbal and still want ref audio or a wireless lav recorded (I don't see any options offered without the handle). On a side note, I recently worked with the C300 MK2 and did not like the monitor and XLR block being tied together either!

Because there are times you have a sound guy, or you don't, or you are a one man band shooting with multiple cameras, I also own DSLRs too and enjoy using the right tool(s) for the job. YMMV.

@flash

So, you want to start real wars on set? :-)

Fx6 gets Netflix approval.

https://partnerhelp.netflixstudios.com/hc/en-us/articles/360000579527-Cameras-and-Image-Capture

If I were ARRI, RED or SONY, I would create an app with the ability to connect multiple users to the camera. DOP, first camera assistant, sound engineer so everyone would have access to partial parameters without overriding those of others ... And there would be a trace of the changes and especially who made them LOL

That's a great idea! (and especially having a log)

As it would be awesome to be able to keep remotely an eye on the audio settings (& timecode too, seeing as that falls under the responsibility of the Sound Dept) on all the cameras on set, and even change settings if need be.

I like the FS5 form factor, buttons are good when you are in hurry! I personally prefer APS-C (will we see a FS-6?)

Personally I want to at least see a "pro" APS-C Sony hybrid camera. As the a6600 isn't it!

The awful rolling shutter needs to be fixed, and the 1080 mode is terrible! (worse than in the old a6000/a5100!)

If Sony simply fixed that in a new "a6700" (or "a7100" or whatever they call it) while holding the price down then I'd be keen as beans for one as a B Cam to my Sony FS7.

Of course ideally it would have 10bit internal and 4K 60fps too, just like the a7Smk3. But then I'd worry they'd push the price too high on a new a6700.