FS7: Recording HDMI 4K vs RAW

J

jpham

Well-known member
Since I don't have the Sony XDCA for raw recording, what's the quality
different between recording from HDMI vs XDCA raw to the O7Q in 4K mode?
 
The RAW suffers from some issues (see threads in this forum) and imho both options are not worth the effort compared to the internal XAVC-I. my 2cts
 
I'm looking for way to record 3-5 hours of continuous video at 4K or even at 1080p. The only way to do it is with external recorder, unless there is a XQD module that can plug into a SSD Sata interface. I test my O7Q+ and it works. Does FS7 noise reduction also reduce noise in HDMI out?
 
You don't indicate the frame rate you wish to record at and when stating 4K you do not indicate if this is DCI or UHD (4096 or 3840). DCI24p is the same amount of data as UHD30p, so I'll calculate for that. To record for 5 hours (300 minutes) it would require one or two 1TB SSDs. Here's what you'd get (approximately, since ProRes is a variable bit rate codec):

DCI4K24p/UHD30p
2TB in Apple ProRes 422(HQ) = 268 minutes (7.64 G/min)
2TB in Apple ProRes 422 = 424 minutes (4.83 G/min)
2TB in Apple ProRes 422(LT) = 648 minutes (3.16 G/min)

For HD (1080p30) the numbers are almost exactly four times the running time for the same amount of memory, or you could calculate it as 1/4 the memory required to get the same running time.
 
At $189 per 128GB XQD card, I think I'll use my O7Q and already bought 1TB SSDs
hard to justify buying 6 hours worth of XQD cards when the project doesn't pay that much.
 
jpham said:
At $189 per 128GB XQD card, I think I'll use my O7Q and already bought 1TB SSDs
hard to justify buying 6 hours worth of XQD cards when the project doesn't pay that much.
Click to expand...
An important point.

Using Samsung 850 EVO 1TB SSDS (technically 1000GB), memory for the Odyssey7Q+ is currently running about 30¢/G, or about $2.30/minute in Apple ProRes 422(HQ) in UHD30p.

Using a128GB XQD card at $189/card, internal memory for the FS7 is running about $1.48/G, or about $4.74/minute in XAVC-I in UHD30p (Based on Sony's listed rate of 3.2GB/min).

Using an Odyssey7Q+, the cost per minute for recording media is less than half that of internal recording on the FS7.
 
jpham said:
At $189 per 128GB XQD card, I think I'll use my O7Q and already bought 1TB SSDs
hard to justify buying 6 hours worth of XQD cards when the project doesn't pay that much.
Click to expand...

When you do the financial math do you have in mind that you will either need the XDCA or the 7Q+?
 
Clermond said:
When you do the financial math do you have in mind that you will either need the XDCA or the 7Q+?
Click to expand...
If he has an Odyssey7Q+ it can accept UHD30p directly via HDMI without either the XDCA or the Odyssey RAW Bundle. In my brief cost comparison I did state that I was only comparing the recording media and I did so in actual dollars per minute, which is the fairest way to run the numbers.
 
Mitch Gross said:
If he has an Odyssey7Q+ it can accept UHD30p directly via HDMI without either the XDCA or the Odyssey RAW Bundle. In my brief cost comparison I did state that I was only comparing the recording media and I did so in actual dollars per minute, which is the fairest way to run the numbers.
Click to expand...


he wrote

.. I think I'll use my O7Q
Click to expand...

he should also consider powering the camera and in case he goes the 7Q7Q+ route powering the recorder as well
 
I still have here a Sony statement that says that UHD 50p/60p cannot recorded with 10bit 422 using the HDMI interface of the FS7. I told that also Mitch, and he had the idea to go back to Sony with that question. Because if the Sony statement is true, then the quality should be very different if one uses an external recorderle th 7Q+ or even the Shogun, compared to he raw ouput of the FS7.
 
Mitch Gross said:
An important point.

Using Samsung 850 EVO 1TB SSDS (technically 1000GB), memory for the Odyssey7Q+ is currently running about 30¢/G, or about $2.30/minute in Apple ProRes 422(HQ) in UHD30p.

Using a128GB XQD card at $189/card, internal memory for the FS7 is running about $1.48/G, or about $4.74/minute in XAVC-I in UHD30p (Based on Sony's listed rate of 3.2GB/min).

Using an Odyssey7Q+, the cost per minute for recording media is less than half that of internal recording on the FS7.
Click to expand...

XAVC-I UHD30p is 300Mbps from what I can see in the spec list so it's a little less expensive than you noted (3.2GB/min is 427Mbps), but you are also comparing an 880Mbps codec to a 300Mbps codec. Perhaps a better comparison is Prores LT to XAVC-I, in which case the cost of recording on the 7Q option is further cut in half.
 
wschmid said:
I still have here a Sony statement that says that UHD 50p/60p cannot recorded with 10bit 422 using the HDMI interface of the FS7. I told that also Mitch, and he had the idea to go back to Sony with that question. Because if the Sony statement is true, then the quality should be very different if one uses an external recorderle th 7Q+ or even the Shogun, compared to he raw ouput of the FS7.
Click to expand...

I'm curious about this as well...does that also apply to 24p / 30p or does the increased framerate of 50/60p necessitate the drop in bit depth?
 
The HDMI-interface supports 4:2:0 8 Bit Signal for 4K/50P. Up to 4K 30p you have 422 10bit. So
4096x2160 60p/50p 4:2:0 8 bit
4096x2160 24p/25p/30p 4:2:2 10 bit
 
If you use the Samsung SSD's in the 7Q+ do you need to power the 7Q using an AC adapter or will it work from the Sony L batts I usually use?
 
wschmid said:
The HDMI-interface supports 4:2:0 8 Bit Signal for 4K/50P. Up to 4K 30p you have 422 10bit. So
4096x2160 60p/50p 4:2:0 8 bit
4096x2160 24p/25p/30p 4:2:2 10 bit
Click to expand...
Wolfgang, I did see this information at another spot in reference to a different product but I am still awaiting a response from Sony. It is quite possible that you are correct but I cannot confirm it at this point.
 
Lenilenapi said:
If you use the Samsung SSD's in the 7Q+ do you need to power the 7Q using an AC adapter or will it work from the Sony L batts I usually use?
Click to expand...
The Samsung SSDs use a marginally higher draw of power, but that just means they will drain your batteries a little quicker. You certainly are not relegated to AC power only.
 
On my last 12hrs shoot, I power my cam (FS700) and O7Q+ on AC. For anything less than 3 hours, I hook the 7Q+ to V-mount battery brick. Convergent sells that custom connector to DTAP, I like the v-mount battery brick, it keeps going and going.
 
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