Anything that is considered 576 lines of vertical resolution (PAL) and below, including NTSC (480 lines of vertical resolution) is SD, standard definition.

heath

Right. That's exactly why I want a RAID +1: to help protect against drive failure.

Incorrect. Technically DV format is in fact nothing more, nothing less than SD. Hope this helps,

haha thats right it is all SD but i meant the quality of Betacam SP is considered better than DV, correct?

No. If you shoot DV/DVCAM and Betacam SP with the same camera, under most all conditions you'll like the look of the DV better. In the early days of DV, before there were 2/3" chip DV cameras, people were always comparing cameras like the PD150 to things like the BVW600, and of course the Betacam camera looked better. But when you compare apples to apples, DV usually wins.

differences between HDV and XDCAM HD@25Mbps
 

I've been reading a lot of great reviews and comments on how superior the XDCAM HD is to HDV, but have this question: both being long-GOP MPEG-2, how does the XDCAM HD at 25Mbps differ from HDV? All other things equal, should there be a difference in quality (theoretically speaking, as we don't have exactly the same cameras with same lens, chips etc. that would be capable of both formats).

The fact that the XDCAM HD cameras are 1/2" chip cameras would make a difference even if all other things were equal. The way to check it out would be to shoot something with the F350 at the lower data rate, then at the 35mbs rate and compare the two shots and see what the difference is. Maybe somebody with the 350 would do that.

Another way to look at it and possibly see how this relates to the different encoding schemes is to try the following:

1. Encode a DVD @ 5 Mbps CBR
2. Encode a DVD @ 5 Mbps VBR
3. Encode a DVD @ 7 Mbps VBR

HDV is CBR, XDCAM-HD is VBR, so 1 is comparable to HDV (25 Mbps), 2 is comparable to XDCAM-HD (25Mbps) and 3 is comparable to XDCAM-HD (35 Mbps).

This approach would leave all other factors out of the equation, including the different chip size.

As I understand it, the main difference between XDCAM at 25 Mbps and HDV at 25 Mbps is that the video is stored slightly differently, but it's essentially the same quality. Also, XDCAM uses uncompressed (PCM) audio while HDV uses MP3 audio at about 1/4 the data rate.

But what's the point of asking? If you had an XDCAM HD camera would you run it at the HDV data rate? Why not get the full benefit of the format by using 35 Mbps?

Well in theory the 25 mbit mode is pretty much the same as HDV but we have to take into consideration that a high end camera may use a much better encoder chip.

Hardware encoder chips are like software encoders where some will do much better then others will. Uusally at higher bitrates it doesn't really matter but when the bitrates get lower a better quality encoder will make a huge difference.

This isn't a perfect science of course, but to me HDV seems like what a DVD would look like with a bitrate of 5.8 mbits/s. Some DVD encoders can look very good at 5.8 mbits/s while some start to drop in quality.

It is safe to assume that a HDV camera costing only $3,000 may not have the best encoder chip in the world while a camera that costs around $20,000.00 will have a much higher quality encoder chip.

35mbits/s to me is pretty close to what a DVD around 8 mbits/s would look like or pretty darn close to perfect.

It is the same reason why a 18 mbits/s HD broadcast can look very good. Some very high quality tens of thousands of dollar encoders are used to make sure the encoding is done well. That same 18mbits/s from a consumer grade encoder chip wouldn't look nearly as good.

Here's a more detailed answer to this question, from http://www.tapeonline.com/faq/xdcam-faq.aspx (I think this same material is also on the Sony web site):

"Q: Does 25 Mbps XDCAM HD recording use the same compression as HDV 1080i recording?

A: Yes. While XDCAM HD recording at 18 and 35 Mbps uses variable bitrate technology, the 25 Mbps alternative uses a fixed bitrate for compatibility with HDV 1080i editors and recorders. Basically the only difference is that HDV editors use Transport Stream (TS) and XDCAM HD uses Elementary Stream (ES). When the PDW-F70 recorder and the PDW-F30 player are fitted with the optional PDBK-102 MPEG Transport Stream (TS) card, these decks can be connected directly to HDV 1080i recorders, camcorders and compatible NLEs, via the i.LINK® HDV interface.*"

Today I was tasked to videotape 4 groups of people using a client’s camera and instead of putting the footage onto tape, he told me to put it on DVDs using the VRD-MC3. It’s basically the quickest way to give each group a DVD of the practice presentations.

Is has a 2.5” LCD screen, fire wire input, analog inputs and memory card slots. Sony has already revealed that the successor of this will be AVCHD compatible so that you can put your HD files on standard DVDs without a computer.
http://www.sonystyle.com/is-bin/INTE...ductSKU=VRDMC3
I was very impressed using the VRD-MC3. A Blu-Ray version of this with SxS card slots would make the perfect companion to the XDCAM-EX. Since Sony is reading that their are a lot of people that would be interested in something like this, I’m sure they wont disappoint.

I'm surprised that nobody has mentioned that the audio on XDCAM HD is uncompressed.

But alas not 4 channel on the EX?

Nobody knows. I don't see why not though. All it would take is for it to record two stereo pairs input via a mixer, just like its bigger brother.

I think the 1/2" chips and manual lens on this camera show the sort of level of user that Sony are aiming at. So I would expect the functions on it to be less dumbed down than most cameras of this sort of form factor.