View Full Version : XDCAM EX SDI 4:2:2 8bit or 10bit?


Steven Thomas
October 23rd, 2007, 02:06 PM
There was some discussion of this on the 4:3 thread. I thought I'd move that discussion over here.

I'm hearing most say 8 bit for SDI, but there still is no documented proof.

This was one of the questions Mark asked at the Sony demo, and the Sony rep replied 10bit. But, I still would like to see in writing.

Marks question thread is here:
http://dvinfo.net/conf/showthread.php?t=105283

Alexander Ibrahim
October 23rd, 2007, 02:21 PM
There was some discussion of this on the 4:3 thread. I thought I'd move that discussion over here.

I'm hearing most say 8 bit for SDI, but there still is no documented proof.

This was one of the questions Mark asked at the Sony demo, and the Sony rep replied 10bit. But, I still would like to see in writing.

Marks question thread is here:
http://dvinfo.net/conf/showthread.php?t=105283

The SDI output will be 10 bits because that's the SDI spec.

The question is subtler: will the data in that 10 bit SDI stream be 8 bit or 10 bit.

When I asked Sony representatives at Professional Products fair I was told 8 bits. That conflicts with the 10 bit answer in Mark's thread- its safe to say there is some confusion on this point within Sony.

I was checking on the answer for the 4:3 workflow thread, and I found no mention of this issue in Sony materials on their web sites or the various brochures at this time.

Craig Seeman
October 23rd, 2007, 05:13 PM
Alexander, I was also told 8 bit by the Sony rep at HD World Expo.

Steven Thomas
October 23rd, 2007, 07:02 PM
I guess we'll have to wait until the information is released.

Thomas Smet
October 23rd, 2007, 10:58 PM
The 10 bit information that Mark got I think was wrong. I thought it might not be accurate when he first told us the answer he got. I'm sure the SONY rep was just barking out the specs of the SDI port itself and had no clue that you could stuff 8 bits inside of 10 bits by padding the last 2 bits with zeros. This just doesn't seem like a fact SONY would train their people to remember. In fact I doubt SONY would even want to say what it really was unless it was 10 bit. If it was 10bit I would think SONY would have used that as a huge marketing tool against other companies who only have 8 bit in their SDI ports.

Peter Jefferson
October 23rd, 2007, 11:37 PM
We asked that question at the Sydney launch and we were told it is true 10bit.

Steven Thomas
October 24th, 2007, 06:17 AM
I hear that, although I can't imagine why they would not of offered 10 bit at that point.
Mark's question was worded correctly, I hope Sony's reps understood the question.

Alexander Ibrahim
October 24th, 2007, 10:41 AM
I hear that, although I can't imagine why they would not of offered 10 bit at that point.
Mark's question was worded correctly, I hope Sony's reps understood the question.

Well I have a call in to the Sony EX engineering rep for my region, so hopefully I'll get word soon.

Steven Thomas
October 24th, 2007, 10:49 AM
Thanks Alexander,
Well, I wouldn't be surprised they're using 8 bit in their 10 bit word.
We can only hope for 10 bit.

Alexander Ibrahim
October 24th, 2007, 10:41 PM
Well I have a call in to the Sony EX engineering rep for my region, so hopefully I'll get word soon.

I got the word back. 10 bit.

Here is how I phrased my question:

"Specifically I am wondering if its 10 bit or 8 bit data. I am aware that the HD SDI specification calls for a 10 bit stream, what I am wondering about is the nature of the data being sent over that stream."

Here is the reply I received:

"...the bit rate at the HD-SDI out is 10 bit, 4:2:2."

As you can see the answer is not as emphatic and clear as we might want, but I think the engineer understood my question and answered appropriately.

For my part, I am going to treat that as the 'final word' until we get cameras in our hot little hands and can test them for 'The Final Word.'

Thomas Smet
October 24th, 2007, 10:51 PM
what a tricky answer. It could still go either way. The guy may not have been allowed to say for sure so he said it the way that would be true even if it is not.

Just because he understood the question doesn't mean he was allowed to answer it fully.

Although for the life of me I can't figure out why SONY would want to hide this. Unless it is 8 bit but they don't want people to think it is 8 bit.

So for me it is still 50/50. It could be either one at this point. I will be happy no matter what it is.

Are the SDI ports on the 330 and other XDCAMHD cameras even 10 bit? I didn't think they were.

Alexander Ibrahim
October 24th, 2007, 11:52 PM
Are the SDI ports on the 330 and other XDCAMHD cameras even 10 bit? I didn't think they were.

The F355 is in fact 10 bit data if recorded live off the camera head. I don't know about the F350

I don't think the F335 has an SDI output- the F330 didn't, at least not standard.

I know the upcoming XDCAM 4:2:2 camera is 10 bit off the camera head via HD-SDI.