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**Patrick** · 15 December 2000, 19:38

Biker, there's actually been a lot of material posted here in the past addressing your concerns. Jeff b used to post often on this topic, but I guess he's busy editing all the time now. Read this thread and if you like what you see, do a Search for more posts of Jeff's.

http://forums.murc.ws/ubb/Forum2/HTML/003691.html

**Dr Mordrid** · 15 December 2000, 19:49

First off by referencing IEEE-1394 you also drag in its accompanying DV codec. Let's get rid of one thing right now: DV is not totally lossless. Far from it.

DV transferred by IEEE-1394 IS lossless in terms of no losses when transferring the video from the cam to the computer and back, but that's the only lossless part. Otherwise the DV codec that is used to compress the video information IS lossy. It uses the same discrete cosine transform compression that is used in MJPeg, MPEG or mod other lossy codecs.

DV also has a reduced colorspace compared to other video formats. It's colorspace is 4:1:1 (NTSC. 4:2:0 for PAL) vs. 4:2:2 for most all analog capture codecs. Simply put: in this case a higher number is better.

This can cause certain kinds of artifact in shadowed or some color areas (red), especially when you try to transcode DV to MPEG. It also can cause problems when compositing overlays or effects in DV without some hardware or software assist to mitigate the problem. Ex: the RT-2000's 4:4:4 compositing engine.

Don't get me wrong. DV is very useful. I use it a lot myself. It's just not as much of a cure-all as some think it is. I still find plenty of use for analog captures, even with the RT-2000.

Dr. Mordrid

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Asus P3B-F 6 PCI
PIII/850
Gigabyte GA-6R7+ slotkey
Matrox G400/Flex3D
Matrox RT-2000
256 megs RAM
Promise SuperTrak100 (4 x 60g IBM 75GXP: 240g RAID0)
AWE64 Gold
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[This message has been edited by Dr Mordrid (edited 16 December 2000).]

**mynx** · 15 December 2000, 22:23

I just finished a one week course for repairing the miniDV camcorders. There are lots of software/consumer problems. Many don't have drivers for macs and windows NT/2000. The camcorder side is a lot more expensive. For the best quality the tapes can only be used once. They don't have erase heads. They just record over what is already on the tape. The playback from the tape can also be lossy, depending on the number/size of errors during playback.

**dchip** · 15 December 2000, 23:26

My Canopus EZDV captures some darn sharp video through the Firewire, but I have to agree it's not lossless. Also, after capturing, working the avi's into mpeg-1 and hoping that somehow the mpegs would look fantastically better than if I had started with analog video has been disappointing. I am fully convinced that firewire capture is never going to become completely pleasing to me until I can capture to MPEG-2 and make DVD's.

Please do not misconstrue this as a condemnation of DV. Playing directly from my Mini-DV Camera into S-video in on my TV is almost like being there and leaves analog video far behind. It's "digital" reprocessing of "digital" video that causes problems. Why?

**Anatoly Neverov** · 16 December 2000, 06:55

I have digital videocamera, Panasonic dx100; its NTSC analog is ez30u. In many cases for me is better to grab and work with analog video than in DV. 2 main reasons:

1. Panasonic (as well as Canon) has a defect: there is a black bar of 6-7 pixels in every frame of the captured video. If I make a film which I record back to miniDV cassette - it doesn't matter, no problem. It is not seen on TV screen. But if I want to add some effects like "screen into screen" - I have already problems sometimes - I have to crop the clip.

2. DV captured clips are dark and bloodless on computer monitor. If I just add a voice/ music, transitions, and change/ remove the position of the clip in the film, after what I record it to miniDV cassette back - it's OK. The film looks just perfect. But if I make a mpeg for watch it on computer monitor - it's a real nightmare! I should make cropping to remove that black bar, and to add filters - saturation, brightness, contrast, etc. Hope you can imagine what piece of work I have then.

If I grab in analog - no bar, and the brightness, contrast and saturation of the image can be ajusted by the driver during the capture.

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**Biker** · 16 December 2000, 08:28

Wow - thanks to all for replies - and so soon. More comments please.

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**Sciascia** · 16 December 2000, 15:55

Not so much a comment as a question. I have been looking at some cameras and figured that the DV codec was lossy. But even with that in mind, I noticed that the quality of the cameras was much higher than the analog ones that I was looking at. How about using a DV cam to record and then using the SHVS connector on the G400 to import the video? It may be a stupid question, but if the picture is higher quality could you "fool" the G400 into thinking that it is a better video source than the DV codec. I probably could have worded this better, but the wife is nagging me to log off. 5 more days till cable modem.....

**Anatoly Neverov** · 16 December 2000, 17:24

That's right what I do. I have Panasonic dx100 (NTSC analog is AG-EZ30U) - 3CCD digital camera. I have PYRO card for capture in DV format and had MIRO dc10plus, which recently substituted to Marvel g400TV. I see that more often I work with analog than with digital signal. The reasons are in my previous message in this thread. But 3CCD is 3CCD, gentlemen. I assure you - the money invested in 3CCD camera aren't lost.

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Anatoly Neverov
Minsk, Belarus

**wkulecz** · 16 December 2000, 22:27

I'm happily using an ADS Pyro and windows 2000. Lack of the 2/4GB file limits is the biggest win for me.

I agree the best thing I could do to improve my overall quality is get a 3CCD camcorder.
It'll probably be my next priority.

Analog is moot since my Marvel lacks usable w2k drivers.

I honestly can't say that analog captures from my D8 camcorder with my Marvel, MJPEG edits, and output back to VHS ends up any worse (or beter) than firewire captures and edited DV sent to firewire and VHS via the camcorder. The editing process is a whole lot easier for me without the 2/4 GB limits though. YMMV.

--wally.

[This message has been edited by wkulecz (edited 17 December 2000).]

**dchip** · 17 December 2000, 08:38

I just might purchase a top quality 8mm or Hi-8 to have on hand and go back to doing some stuff with the Marvel G200 or even my ancient Happaugue WinTV-HQ ISA card, which by the way, always captured very nice video. I will still do longer projects that need a lot of fancy transitions and 3-D objects etc. using the digital equipment and software.

A year ago, wild horses couldn't have kept me from upgrading to digital, but now I realize that I might have been off base in expecting to completely abandon analog.

**Anatoly Neverov** · 17 December 2000, 09:08

wkulecz: 2/4GB file limits is not such a big problem as maybe it seems to you. I use AVI_IO and don't feel this problem at all. Some of my friends installed W2K and during several weeks I have admired their agonies with various drivers, screen ajustments, sound problems, and so on. I have decided to wait better for a while, until comrade Gates makes all necessary improvements in his new monster. For the moment I'm more than satisfied by AVI_IO for $25.00/ one piece. Besides: many programs, like VideoWave 4.0, Miro and DV Studios, and tons of others use now the idea of AVI_IO - they just split captured and output files in pieces of size less than 2/4GB limits and work with those pieces like with one. If you aren't very snoopy person, you may even not know in how many of pieces is cutted your raw and output files; you work with them like with one.

Recording to the camera/ VCR is one thing. But try to make a *.mpg file which is intended to be watched only on computer screens. You will immediately feel and appreciate the difference between analog and DV capture.

Sciascia: I don't know much about the theory of the capture, but from my practice I see that if I prepare a film for recording onto miniDV cassette, I should use DV capture and edition because this gives the best possible quality I can get; in ALL the other cases (without exceptions!) I like the result of work in analog format much more. So, your theoretical conclusions are fortified and perfectly acknowledged by my practice. We found each other in this world eventually!

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Anatoly Neverov
Minsk, Belarus

**wkulecz** · 17 December 2000, 09:25

If you are recording with an NTSC DV camcorder your colorspace is 4:1:1 on the tape. I don't see how analog capture can do anything to restore the colorspace if that really accounts for the problems in MPEG quality when made form DV sources.

I've had far fewer problem with windows 2000 that *anything* else that Mr Gates has stuck us with. But then I've only bought quality components from reliable manufacturers -- only Matrox and ATI have let me down!

--wally.

**Sciascia** · 17 December 2000, 17:14

I would assume that MJPEG or Huff would recompress better than DV because of the colorspace difference. Even though the source is actually recorded with 4:1:1, if it is as high quality as it looks on a monitor, then encoding it in analog with a 4:2:2 or even 4:2:0 colorspace, then the output of an MPEG encoder should look a little better. Of course I haven't tried this myself. I understand what the Doc is talking about, if your chroma has less bandwidth, then your your MPEG encoder has less information to read. But if your analog input sees a high quality image, then it should be able to fudge the colorspacing and give you a nice high quality capture.

**Anatoly Neverov** · 18 December 2000, 07:43

Grigory: The key of your scripture is: "I can agree that converting from DV to mpeg1 may require filtering and level adjustment. Both actions can be easily performed by VirtualDub or AVIsynth."

Or, these actions can be much more easily performed just by grabbing through analog.

Everything depends on what kind of video you are making more often. If mpegs for VCD's - you will economize a lot of time using analog capture, if you produce the video for TV screen - you should use DV format. Nobody argues with that. I just am making MAINLY mpegs, and I use MAINLY analog capture. For not to wait hours till my captured clips will be ajusted by the Dub. That's why I have got Marvel and have had Miro. But when I make a film for recording back to DV cassette I use DV format.

If you know how to force Marvel's tuner to work with Soviet SECAM - please contact me privately.

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Anatoly Neverov
Minsk, Belarus

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