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What’s HDV like for everyone?
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The HVX200 sounds nice and flexible, but until we see the pictures from it.
Same as the Varicam Graeme, Leica glass, I should b able to show some of the content from it at HDEXPO Midwest on May 17th
A note however the camera only does HD and the VFR capture to P2 cards –NOT to tape.
The tape mechanism in the camera is dv25 only (I believe that it is the same/ similar to the one in the DVX100a – but I am not sure)5:30P – 6:30P THE MAGIC TRIO – Using The Varicam, 1200A Deck With Fire Wire and Final Cut Pro HD
The Tips, Do -
The HVX200 sounds nice and flexible, but until we see the pictures from it.
Same as the Varicam Graeme, Leica glass, I should b able to show some of the content from it at HDEXPO Midwest on May 17th
A note however the camera only does HD and the VFR capture to P2 cards –NOT to tape.
The tape mechanism in the camera is dv25 only (I believe that it is the same/ similar to the one in the DVX100a – but I am not sure)5:30P – 6:30P THE MAGIC TRIO – Using The Varicam, 1200A Deck With Fire Wire and Final Cut Pro HD
The Tips, Do -
Yes, just as in any lens system, as the iris is opened up (made larger), the depth-of-focus is reduced. This gives the subject a sharp focus while putting foreground and background objects out of focus…a more pleasing image to most people except maybe camera engineers. Using a more telephoto side of the lens exaggerates the effect and using a neutral density filter restricts light so that the iris can be used at a bigger f stop. It’s just one part of the look of film cameras that most people find pleasing.
As for the keying comment – If you have a capture system that will allow for HD uncompressed (no codec, raw video) capture, it is best to use that for any bluescreen keying or special graphics work. Although the original HDV footage is highly compressed as mentioned, it is a different type of compression (MPEG-2) that relies heavily on the frames preceding the frame being compressed. It consists of a group of pictures (GOP) that get the color and luminance ques from the first frame in that group. This makes for excellent reproduction but horrible editing. If the codec was used to edit, only cuts would be allowed at the first frame of GOPs and that would be very restrictive. So when the video is uncompressed, the system actually has to work LESS because it’s not decoding a codec and it’s using the best possible image quality. Hardware (Decklink, AJA, Avid, etc) is the only way to edit uncompressed – or at least, get it into and out of the system.
System A Info G5/Dual 2 – 10.3.6 – QT v6.5.2 – 4GB ram – Radeon 9800Pro – Lacie FW800 L1 RAID via Lacie PCI card and internal – Decklink Extreme – Wacom 6×8 System B is identical except: 2GB ram – Decklink SP – Radeon 9600 – Pro Tools
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HDV is highly compressed and editing it as uncompressed does not improve that quality one little bit, and in reality, you’re trading less processing power needed for more hard drive size and speed needed. You’re not altering the absolute quality of the video one little bit. This may be advantageous if you render the final output uncompressed to go out over SDI to a high end HD deck like HDCAM SR or D-5, or even DVCproHD or HDCAM, but will be of no benefit for going back out to HDV, and probably marginal benefit at best for making a HD-DVD or H.264 DVD.
As for keying – HDV is 4:2:0 and hence has as bad as color sampling as PAL DV, and in numerical terms, the same resolution loss altogether as NTSC DV, and as it’s even more highly compressed, will in all likelyhood pull a worse key. However, due to it’s higher resolution, the artifacts from the key will be smaller, but they’ll still be there. Even HDCAM is not the easiest format to pull a key from – as hard as DV in my experience.
Graeme
– http://www.nattress.com – Film Effects for FCP
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Graeme, my point is that the codec itself is based on a completely different encoding technology and making comparisons to the DV codec by mere numbers will not be accurate. I agree that the video will never gain resolution simply by going in uncompressed, but the added effects WILL be using a more accurate sample than with other compression schemes – and the output will be cleaner than simply keying – unless Apple has found a way to de-compress the HDV stream in realtime. The complexity of the HDV codec, or any MPEG-2 image, is why it cannot be compared to DV simply by compression ratios and pixel counts.
System A Info G5/Dual 2 – 10.3.6 – QT v6.5.2 – 4GB ram – Radeon 9800Pro – Lacie FW800 L1 RAID via Lacie PCI card and internal – Decklink Extreme – Wacom 6×8 System B is identical except: 2GB ram – Decklink SP – Radeon 9600 – Pro Tools
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But FCP5 does indeed decompress HDV in real time and also allows full native editing of the MPEG2.
Sure, you can’t compare codecs directly, but the current figure for HDV type MPEG2 efficiency over that of a DV type codec is about 2.5 times. Given that it’s compressing 4.5 times as much data per second, you can see where that leaves us….
Graeme
– http://www.nattress.com – Film Effects for FCP
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[Will Salley]
A few opinions on the HDV codec and the Z1 specifically:
– The color accuracy is much better than with DV. I have successfully done green-screen with good results. The tip is to capture uncompressed for any keying work.I am with Graeme on this, it is not better than DV, but my question will is are you using the HDV contnet as HD or SD. In the SD downconvert of this content that maight be true but certainly not in the HD content.
– Sound quality is excellent (at least on the Z1).
???? not on my system the HDV codec uses mpeg 1 layer 2 audio this is a 5:1{?} lossey compression for audio it is no where near as good DV’s 48k Aiff audio. Maybe the mike on the camera is better but not what is on the tape.– Since the codec works in a completely different way than the DV codec, the artifacting we all hate has been greatly reduced with HDV, but at the expense of increased potential of motion artifacts.
the HDV compression is taking that 1.5gigabit date stream (an HD standard that does not change because of HDV @ 1920x1080i x 29.97) and compressing it to an 11 micron tape head your talking about a 60:1 data compression (NOT IMAGE compression) when using the Native HDV codec at 25mbps.
One last thing Will, how are you dealing with HD when your Sig file does not list any HD hardware, the DL boards you list are just SD only. Viewing these files in
HD, on a real HD display might change your mind to some of the things you comment on.gary adcock
Studio37
HD and Film Consultation -
You can talk numbers until you are blue in the face, but it’s really down to how the pictures look on the monitor and what sort of work you want to do with it. If you want to key, then HDV is functional, but no better than DV as Graeme says (he’s also right about HDCam – I was so surprised when I tried to pull my first HDCam key – it was as tricky as DV!)
However the image quality from HDV is very impressive, we have replaced our PD170’s with Z1’s and have had no real problems. Sure the HVX will certainly be better quality, but it’s not out yet and you have to be able to fit in with the P2 workflow.
The simple answer is try it yourself and see what you think!
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I don’t want to get in a roundabout argument here but.
My OPINION is:
– The HDV codec is far superior to pixel/chroma-based codecs and produces better keying than those codecs.
– The sound quality is BETTER than other DV or HDV cameras beause of several factors including a true balanced input and better design. I have not noticed, by ear, any noise level difference between MPEG-2 audio, and DVCAM. I have noticed it is has a better signal-to-noise ratio than BetaSP, which is still the industry standard (most widely used) for broadcast. By the way, I don’t use the camera mic, I primarily use a Sennheiser 416 or 418 shotgun mounted to a an overhead boomploe via a Rycote shockmount. This goes through a Sound Devices 302 or 422 mixer and then to the camera via XLR. I have been doing professional location sound for 18 years.
– I didn’t say that keying HDV was easy. It simply produces much better results than DV (when keyed uncompressed).
-My system setup profile is slightly out-of-date. I have a Decklink HD and monitor through a Cinema Display /HDLink and a Samsung DLP HD display (up-ressed from 720).System A Info G5/Dual 2 – 10.3.6 – QT v6.5.2 – 4GB ram – Radeon 9800Pro – Lacie FW800 L1 RAID via Lacie PCI card and internal – Decklink Extreme – Wacom 6×8 System B is identical except: 2GB ram – Decklink SP – Radeon 9600 – Pro Tools
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