HDV to analog video at DVinfo.net

Saul Martinez · March 7th, 2007, 11:50 AM

Can I down convert HDV to analog video through the Components outputs of my HD100 camera? Is there any lost of quality? Thanks.

Ben Lynn · March 7th, 2007, 02:11 PM

When you watch anything off the component outputs your already watching in an analog format. So you could buy a component HD capture card and capture material right off the camera that would be ready to put in the timeline, no intermediate conversion.

I can't say exactly what the quality loss would be, but there is some in the conversion to analog using the component outs. Would you notice it? No. Even when you capture as m2t down firewire you have to convert to an intermediate codec and there's some type of quality change in that decompression phase. Again, would you notice it? No.

I'm not sure about the HD-SDI out of the 250 but that would probably provide the best possible out from this camera line.

Ben

Saul Martinez · March 7th, 2007, 06:34 PM

Thanks, Ben.

Daniel Patton · March 7th, 2007, 10:24 PM

Quote:

Originally Posted by Ben Lynn

When you watch anything off the component outputs your already watching in an analog format. So you could buy a component HD capture card and capture material right off the camera that would be ready to put in the timeline, no intermediate conversion.

I can't say exactly what the quality loss would be, but there is some in the conversion to analog using the component outs. Would you notice it? No.

Ben

I'm not sure I agree with this, except for the quality hit you take from the digital to analog conversion on the HD100. We did notice it and found little to nothing gained going that route. If you capture to tape with HDV compression and then take it out component, you have now taken two quality hits, it does start to go a tad soft. Component is best left for playback and to monitor during a shoot, but once you have gone to tape you might as well work with firewire if you want to retain as much quality as possible.
This was just our findings, your mileage may vary.

The HD250 and HD-SDI is very nice indeed, no issues there.

Saul Martinez · March 7th, 2007, 10:37 PM

Daniel, as I read, firewire can't out HDV video only DV. Is it correct?

Jason Nolte · March 7th, 2007, 10:40 PM

If you are recording to tape and then capturing, firewire is the highest quality. It's a 'bit for bit' digital connection - no loss. HD SDI has a tiny bit of loss.

If you are capturing off of HD SDI a live feed to a capture board, you can get uncompressed HD, without the mpeg2 HDV compression.

Daniel Patton · March 7th, 2007, 11:20 PM

Quote:

Originally Posted by Jason Nolte

...HD SDI has a tiny bit of loss.

Hey Jason,

I'm not sure I'm clear on this. So SDI has a tiny bit of loss regardless or do you mean from tape/HDV out SDI? If so how can you guage if there is any loss on the SDI end of things, or if it's simply the HDV compression as expected? Since the only better quality workflow is the same SDI as uncompressed.

I'm genuinely curious. How can this be measured without some form of raw data to compare the SDI to?

Sorry, didn't mean to hijack the thread.

Bill Ravens · March 8th, 2007, 08:44 AM

1-firewire can output DV or HDV, no problems with either. Firewire canNOT do HD.
2-If you're chromakeying, direct capture from component out may be better because you have 4:2: color mapping. If chromakeying isn't an issue, the highest quality process is to m2t>intermediate.

Jason Nolte · March 8th, 2007, 08:49 AM

Quote:

Originally Posted by Daniel Patton

I'm not sure I'm clear on this. So SDI has a tiny bit of loss regardless or do you mean from tape/HDV out SDI? If so how can you guage if there is any loss on the SDI end of things, or if it's simply the HDV compression as expected? Since the only better quality workflow is the same SDI as uncompressed.

HD SDI has a tiny bit of loss, regardless. If you are capturing off of tape, you are also dealing with the mpeg2 HDV codec compression as well. However, even if you are shooting and capturing a live feed directly into a capture board with HD SDI, you still are getting a tiny bit of loss. But not to be confusing, we're talking miniscule amounts here - nothing that I think is perceivable from the human eye.

Don't get me wrong, HD SDI is a great solution. Instead of wrangling 5 cables plus reference, you can use one digital cable that carries everything in much higher quality.

Quote:

Originally Posted by Daniel Patton

I'm genuinely curious. How can this be measured without some form of raw data to compare the SDI to?

It can be measured:
HD-SDI has its variants which can transmit full-bandwidth, 10-bit RGB and an alpha channel to boot.
(All you ever wanted to know about HD SDI and more)

Daniel Patton · March 8th, 2007, 11:20 PM

Jason, Thanks! That's a great white paper on SDI, and I only had to read it maybe 3X before it started to stick. I prefer to dig as far down as I can. ;)

However, unless I'm reading it wrong it described the transmission of digital data over SDI as "lossless compression". Although the signal is transmitted over "low loss" coaxial cable I didn't get the impression the loss effected the transmitted image per say, but simply that it had to stay within a sufficient range in order for the receiver to recognize and reconstruct the data bits. Either the receiver obtains enough signal or it doesn't.

I got the impression that even though the received data had some edge jitter due to the receivers re-clocking, as long as the clock cycle remained intact the data also remained intact. So the signal could have an acceptable loss, or be low but that it did not necessarily equate to a loss in image quality, it just required a better receiver. Is this close or am I missing something?

Peace!

March 7th, 2007, 11:50 AM	#1
Saul Martinez Regular Crew Join Date: May 2004 Location: Guatemala, Guatemala Posts: 63	HDV to analog video Can I down convert HDV to analog video through the Components outputs of my HD100 camera? Is there any lost of quality? Thanks. __________________ Saultv

March 7th, 2007, 06:34 PM	#3
Saul Martinez Regular Crew Join Date: May 2004 Location: Guatemala, Guatemala Posts: 63	Thanks Thanks, Ben. __________________ Saultv

March 7th, 2007, 10:37 PM	#5
Saul Martinez Regular Crew Join Date: May 2004 Location: Guatemala, Guatemala Posts: 63	HDV through firewire? Daniel, as I read, firewire can't out HDV video only DV. Is it correct? __________________ Saultv

March 8th, 2007, 11:20 PM	#10
Daniel Patton Major Player Join Date: Apr 2005 Location: Knoxville TN Posts: 589	Jason, Thanks! That's a great white paper on SDI, and I only had to read it maybe 3X before it started to stick. I prefer to dig as far down as I can. ;) However, unless I'm reading it wrong it described the transmission of digital data over SDI as "lossless compression". Although the signal is transmitted over "low loss" coaxial cable I didn't get the impression the loss effected the transmitted image per say, but simply that it had to stay within a sufficient range in order for the receiver to recognize and reconstruct the data bits. Either the receiver obtains enough signal or it doesn't. I got the impression that even though the received data had some edge jitter due to the receivers re-clocking, as long as the clock cycle remained intact the data also remained intact. So the signal could have an acceptable loss, or be low but that it did not necessarily equate to a loss in image quality, it just required a better receiver. Is this close or am I missing something? Peace! __________________ Our eyes allow us to see the world - The lens allows others to see the world through our eyes. RED ONE #977

March 7th, 2007, 02:11 PM	#2
Ben Lynn Major Player Join Date: Mar 2003 Location: Bloomington, IL Posts: 636	When you watch anything off the component outputs your already watching in an analog format. So you could buy a component HD capture card and capture material right off the camera that would be ready to put in the timeline, no intermediate conversion. I can't say exactly what the quality loss would be, but there is some in the conversion to analog using the component outs. Would you notice it? No. Even when you capture as m2t down firewire you have to convert to an intermediate codec and there's some type of quality change in that decompression phase. Again, would you notice it? No. I'm not sure about the HD-SDI out of the 250 but that would probably provide the best possible out from this camera line. Ben

March 7th, 2007, 10:40 PM	#6
Jason Nolte Regular Crew Join Date: Jan 2007 Location: Denver, CO Posts: 29	If you are recording to tape and then capturing, firewire is the highest quality. It's a 'bit for bit' digital connection - no loss. HD SDI has a tiny bit of loss. If you are capturing off of HD SDI a live feed to a capture board, you can get uncompressed HD, without the mpeg2 HDV compression.

March 8th, 2007, 08:44 AM	#8
Bill Ravens Join Date: Nov 2001 Location: santa fe, nm Posts: 3,264 Images: 10	1-firewire can output DV or HDV, no problems with either. Firewire canNOT do HD. 2-If you're chromakeying, direct capture from component out may be better because you have 4:2: color mapping. If chromakeying isn't an issue, the highest quality process is to m2t>intermediate.