Sony NEX FS700-4K?
- Thread starter billh
- Start date
Unless the camera compresses the data before it leaves the camera, I suspect the 4K frame rate will be limited to maybe 30 fps.
Billy Barber
Member
Or burst mode at 4k possibly.
Yeah, I was thinking sustained rate.
Steve Castle
Well-known member
NO
3G-SDI is and interface that transports DATA. It tells you in its name, "3G" in "3G-SDI" stands for "3Gbps". It is NOT limited to 1080/60p. Its limited to "3Gig" speeds.
Keep in mind, HD-SDI and 3G-SDI are not required to be interoperable amoung vendors. Each vendor creates its own interpretation of HD/3G-SDI specifications. This is specifically the reason why there are sub-specifications, such as HDcctv, that resolve these interoperability issues, and allows for plug-and-play capability, as well as forwards or backwards compatibility.
In fact, SMPTE doesn't even put forth an electrical testing standard on the SDI interfaces. Meaning that there can be not only difference between vendors, but even between prototyping and production stages. The specifications itself are very vague, and allows for many vendor interpretations. There is no 3G-SDI testing and certification process, which is what you see with other interfaces (USB, HDMI, etc.) For instance, a USB device has to be "USB certified" to be called "USB" and it needs to work with any USB port. HD/3G-SDI is not designed the same way.
Which is the point. There is no overreaching standard in SDI for what gets transferred over it. Which is why you see so many SDI devices. Phantom's Cinemag supports 450 fps at 1920 x 1080, we see Arriraw T-link (which is a seperate certification) that records in 2880 x 1620, etc. It can be 4;4:4, it can 8-bit, it can be 12-bit, it can be 3D, it can be non-standard resolutions. Its limited to "3Gig" speeds.
Barry_Green
Moderator
YES
It is a 3-gigabit data pipe, yes, but it is not some proprietary connection. Plug something in that uses 3GSDI and see what you get -- you get SMPTE 424M data transported over it.
Now, as has been said many times, if Sony wants to go outside of the specification (like they did with timecode on the HDMI) then they could design something different over that data pipe. Just like they sent compressed DV data over the SDI port on their early DVCAM decks (and called it QSDI or STDI). But that wasn't an HDSDI connection at that point -- it was a new, customized data feed. And that's what they'd have to do if they wanted to transport anything other than SMPTE 424M over a 3GSDI port.
Well ... if you say so. The world I'm used to, an HD-SDI output plugs into an HD-SDI input, and works, because everyone is working off of the SMPTE standardized transport protocols.
In Sony-land, of course, standards are there to be ignored whenever they feel like it, which is annoying but not always bad. They put timecode in the HDMI port even though HDMI, by specification, does not support timecode. They put DV data on the SDI port even though, by definition, HD-SDI doesn't transport compressed data. They invented a 4-pin "I.Link" connector instead of using the (otherwise standardized) 6-pin.
It's common, it's understood, it's The Sony Way Of Doing Things.
So, as has already been acknowledged, they could try to implement some proprietary protocol to implement raw data transfer over the 3GSDI port. It CAN be done, but to say that the SDI port is a free-for-all for anyone to do whatever they want on it, is not reflective of my decades in the biz.
Of course there is. How can you say something like that? The standard is set by SMPTE. And yes, as has already been said, Arri uses a data transport protocol over two SDI ports that's called T-link, but note -- it's not called HD-SDI or 3GSDI at that point, it's called T-Link. Which is the right way to do it.
If Sony wants to call the 3G-SDI port a "3G/HDSDI & Raw" port, that's fine. I guess it gets into semantics at that point.
Of course, if they'd just invented their own name for it in the first place, and called it "S-Link" or something like that, then there wouldn't even be a discussion. They could have called it "S-Link" and when people ask "what in the heck is an S-Link port?" they could say "Well, it's a BNC connector that can transport SDI, HD-SDI, 3G-SDI, and Sony Raw data at up to 3gbps speeds." And at that point it would have made sense.
Barry_Green
Moderator
And perhaps, if they'd done that, maybe they could also explain how they're getting 4k raw data over a 3gbps data pipe anyway. Maybe that "S-Link" port isn't truly limited to 3gbps? If it's a Sony custom port, maybe it's capable of 5gbps or 6gbps or something, fast enough to accomodate 3GSDI but also fast enough to accomodate a 4k raw data stream... if that's what they've done it would certainly make a lot more sense.
Cosimo Bullo
Veteran
What I think is interesting is that many of us started getting excited about this camera because of the rumored 4k, but now it's the high rates and very good look - not to mention NDs - that have us jonesing! 4k would be a plus, but this camera will sell in any case.
I'd have liked this camera more if Sony had thrown caution to the wind and enabled at least 10-bit on the 3G-SDI. I mean, they charge extra for the port (actually extra-extra, in that they could've charged somewhat less for an HD-SDI), but it's not being used to its advantage and won't be until the 4K upgrade is released. But whether you buy that upgrade or not, you still have to pay extra for 3G-SDI. Of course, if Sony had included 10-bit output, that might've hurt the F3.
Cosimo Bullo
Veteran
This camera will, I think, hurt the F3 no matter how you slice it, especially is they've dealt with all moire issues.
Sage
Well-known member
KyleProhaska
Veteran
I think Sony will snag some on the fence Scarlet buyers if the camera really delivers the goods. Some are still unsure if it's the right time for them to go all in with 4K, and this new Sony provides a lot of the benefits of Scarlet minus RAW R3D...but still keeps the possibility of 4K out eventually in an uncompressed format, along with the slow motion results. Scarlet is pretty soft at 2K, but this camera will likely give a better 1080p image since that's how it's being sold initially. The great (hopeful) 1080p with FPS options, outputs, 4K upgrade, etc. makes it a pretty attractive piece of gear IMO.
It's pretty safe to say I'm more interested in this camera then I was the Scarlet, since going RED (although great) would require a serious overhaul on my end to really make it worth it.
It's pretty safe to say I'm more interested in this camera then I was the Scarlet, since going RED (although great) would require a serious overhaul on my end to really make it worth it.
Steve Castle
Well-known member
First off, I think I've corrected you in the other thread, but SMPTE 424M is just another name for 3G-SDI. Its an interface, its not SMPTE 424M "data". These are very serious semantic transgressions.
Again, there is no guarantee of interoperability between SDI devices, which is why there are sub-standards and certifications WITHIN SDI. Such as HDccTV certification, which is recognized by the SMPTE:
More info here (and a basic explanation of why we need these sub-specifications within SMPTE's SDI interface);
http://www.highdefcctv.org/hdcctv-specification
There is a very deliberate reason why 3G-SDI is called 3G-SDI instead of something like HD60-SDI. Keep in mind, we've moved from "SD-SDI" to "HD-SDI", to a name that indicates mere data. 3G-SDI has evolved into an interface platform. The reason of course is that we've moved beyond HD. What you erroneously call "SMPTE 424M data" is uncompressed 10-bit 1080/60p at 4:2:2 YCBCr. In legacy definitions, what is "SD" and what is "HD" is very simply defined. 10-bit 4:2:2 was enough, cameras didn't take 60fps+ frame rates, bayered RAW, and 1080p+ video. That's what dual HD-SDI, 3G-SDI, and dual 3G-SDI connectors have been used for are beyond those standard HD definitions. They are for 4:4:4, very high frame rates, bayered raw sensor data, and non-standard resolutions beyond what most current display devices can show.
Your misconception is that 3G-SDI is interoperable between vendors and that there is some overreaching standard. There's not. Hiterto, compatibility was really provided by vendors that seeked to maximize their market base and a generally homogenous resolution and frame rate output provided by cameras. The fundamental SMPTE standards are far too nebulous insure those interoperability in the modern camera market that has the camera side moving FAR FAR beyond widely available display technology.
As far as this Sony cam, I'm guessing it'll work something akin to the F65. The F65 outputs 16-bit 4K RAW at 19 Gbps, well beyond any interface standard. That's compressed down to 5Gbps and recorded to SR. The rumored 12-bit output would mean that 3Gbps would need to take a similar route. I'm sure that same 3G-SDI port can still output more standard 1080p resolution for monitoring.
AGAIN, so you don't regurgitate the same arguments. 3G-SDI is not limited to 10-bit 4:2:2 1080/60p, it was designed to be much more flexible than that. Its an just an interface and has become a platform for other standards. Don't mix up the interface from the data that is transported over it. Its going to move beyond just single 3G-SDI connections into dual, and maybe even quad, 3G-SDI connections as technology demands. We're going to see more than just "S-links" and Arri "T-links", but maybe Panasonic "P-links" and JVC "J-links". 3G-SDI allows for that.
Cosimo Bullo
Veteran
Good knowledge.
Zephyrnoid
Veteran
Boy that's for sure. That's the fundamental flaw in the Video World. Non-Interoperability in defense of proprietary 'flavors' so as to corner the market or trip someone up.
Is this ever going to stop ??
I'm confused. If the F65 outputs 16-bit 4K raw at 19 Gbps, at what point is it compressed to 5 Gbps? I assume that if 19 Gbps is too great for 3G-SDI to handle, compression occurs in-camera. If that's true, then the F65 doesn't output at 19 Gbps, but at 5 Gbps. But isn't even that too great for 3G-SDI, or are you saying that Sony has decided to use the interface and just pump through a higher-data-rate stream?
Steve Castle
Well-known member
It won't stop and it'll get much worse. Whenever Panasonic brings out their high end-professional camera, we should assume they aren't going to stop at 10-bit 1080/60p 4:2:2. It would be a tragedy if it did. Its would require a new interface based on either HDMI or 3G-SDI. If you look at a lot of the dual-link HD-SDI/3G-SDI cameras all of them are somewhat ad-hoc solutions; PMW-F3, Arri Alexa, Phantom Flex, and this new FS700. With 3D cameras, 1,000 fps cameras, 4K, and soon 8K cameras, its going to be worse before it gets better.
F65 outputs uses a 20MP+ 8K sensor to output a 16-bit 4K RAW at 19 Gbps. That's output from the sensor. F65 records that RAW to the SR-R4, which is suppose to be an exclusive on-board recorder for the F65. It doesn't use 3G-SDI as its not sufficient for the data rate, it docks directly onto the F65.
snowleopard
Well-known member
Haven't been able to read all the posts, suffice to say, I'm impressed. As I believe Barry once said, the bigger they are, the harder they hit.
Also think this is cagey of Sony to announce this just before NAB. Their target audience, the pros and geeks are always watching, and here we are...
Also think this is cagey of Sony to announce this just before NAB. Their target audience, the pros and geeks are always watching, and here we are...
bgundu
Veteran
Here is some footage. Still looks like FS100 with higher frame rates. The highlight roll-off is killing me.
http://player.vimeo.com/video/39839187
http://player.vimeo.com/video/39839187