SRW-1 Likely Not Capable of True RGB 444 50p Playback

V

Viddovation

Veteran
So, I've been digging through the SRW-1 service manual, trying to figure out how the control signals work, and I came across the following:
Sony SRW-1 Service Manual said:
HDCAM-SR decoding
The played back data is re-converted to parallel data on the DPR-232 board, and is then input into
PIERRE * (A) IC900 and PIERRE (B) IC1100 through the FPGA IC1400.
PIERRE is a data compression decoder of HDCAM-SR. Two ICs of PIERRE are used for the 4:4:4
signal, 4:2:2 50p/59.94p signal or the dual stream 4:2:2 signal, and one IC for the 4:2:2 signal as in the
case of MARIE. The PIERRE output data is converted to serial data by the FPGA, and is then sent to the
DIF-142 board.
When HKSR-103 is attached, the 4:4:4 50p/59.94p signal playback format is 4:4:4 25PsF/30PsF, which is
simple playback for thinning every other frame.
Click to expand...

Bottom line - it would appear that while the SRW-1 with HKSR-103 can record true RGB 444 50p, it will only play that same gootage back at 25PsF, dropping every other frame. If this is true, a tape based workflow for this framerate and color space would require a different deck for ingest.

Anyone know more about this?
 
Hi Viddo

I believe the SRW-1 was never meant as an ingest deck, there was a much larger deck for that.

However this is interesting nonetheless, I was hoping it would be possible to play back at "half speed" because let's face it - we only shoot 50P to do slow motion.
 
Don't we have a few here who bought camera with the recorder? Maybe they can test this. Hunter?

But it is strange it doesn't play back in 24p. So you have to capture in 25p and slowdown 4%? Sounds so 90's.

Can you use any HDCAM SR tape to record 12 bit 444 or there is special one?
 
SJX I'm pretty sure it will play back 24fps material.

It just says 50fps material is played back at 25.
 
JMtheDP said:
Hi Viddo

I believe the SRW-1 was never meant as an ingest deck, there was a much larger deck for that.

However this is interesting nonetheless, I was hoping it would be possible to play back at "half speed" because let's face it - we only shoot 50P to do slow motion.
Click to expand...
Oh, I totally agree. But the proper HDCAM-SR decks for ingest and broadcast playback are ridiculously expensive. I don't think many of us second hand F35 owners are likely using HDCAM-SR recording on a regular basis, but there was a recent discussion on methods of getting the most out of the camera, and the limited number of recorders that can do the high end fuctions. Some may have assumed the SRW-1 could have done this. So I just thought it was a good clarification to make.
 
Definitely, I certainly would have assumed it could play out the 50P footage. I thought it did it by running at the 25P speed, thus giving you slow motion.
 
JMtheDP said:
Definitely, I certainly would have assumed it could play out the 50P footage. I thought it did it by running at the 25P speed, thus giving you slow motion.
Click to expand...

Oh, i see what you're suggesting. Actually, that part likely works. But with a caveat.

See, the finding here is that the recorder can't play back footage recorded at RGB 444 50p/59.94p. But, when you want to record slow motion, you actually use the menu settings to instruct the recorder what the desired playback rate is.

Read pages 81-83: http://pdf.crse.com/manuals/3854913081.pdf

To do what you'd like to do, you'll need to have both the HKSR-102 (SRMotion) and HKSR-103 (RGB 444) boards installed in the SRW1. The key is, if you record the 50p to a 25p container (essentially record at 2x real time) then when the deck goes to playback it's already 25p, and can playback correctly.

What you cannot do is record RGB 444 50p as RGB 444 50p, and play it back in realtime without skipping. Record it as slow motion in the first place, you're okay.

By the way, if you look carefully at the dock port on the F35 that the SRW-1 and IF box use, you'll see six big connectors, a center pin, and something like 17 small connectors. The six big connectors are SDI ports. In relation to the F35 or the SRPC, 4 of them are outputs, and two of them are inputs. RGB 444 50p requires quadlink SDI, and the connector only has that as an output to the recorder, not as a return feed. So it's a physical bottleneck, at a minimum.
 
Yeah I have an SRW1 with the SRPC1 dock, I still haven't tried it yet other than turn it on and pop tapes in and out of it- I will try it when I get back (I'm on vacation!)
 
Doing a bit more reading found this post:

JMtheDP said:
the HDCAM SR deck will do ramping, 4:4:4 50p with the proper cards installed.

It will NOT do 12-bit. Some other recorders WILL (eg. Codex Onboard). The HDCAM SR cannot because 12-bit is not in the SR tape spec. Simple as.
Click to expand...

So HDCAM SR tape is just 10 bit and 12 bit feature in SRW1 is redundant?
 
I can't really say much about the SRW-1, not owning one, but HDCAM SR tape is 10-bit and to my knowledge cannot be 12-bit. It's just not in the spec.

12-bit was introduced some time after the camera came out, I believe it was mostly used with the Codex recorder.
 
This is really strange and surprising the same time because we have now been talking for longest time SRW1 and codex is the only way to record all the camera can and now SRW1 can't record 12 bit HDCAM?
 
SJX said:
This is really strange and surprising the same time because we have now been talking for longest time SRW1 and codex is the only way to record all the camera can and now SRW1 can't record 12 bit HDCAM?
Click to expand...

We're all learning as we go. 12bit RGB 444 wasn't in the early firmware for the camera, so it's not a huge surprise, I suppose.
 
To be honest the above would only be a surprise if you've only recently come to the camera. You have to bear in mind the SRW-1 deck was originally the only thing capable of handling everything the camera could do, as well as the only thing that would dock with it. When the Codex, etc... came out, Sony released the firmware upgrade to help boost the camera's features.

I personally think 12-bit, although nice, is probably overkill for most people. I can't even think of many formats that can store it efficiently.
 
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