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Old 12-12-2013, 07:34 PM   #21
dpalomaki
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Dropping frames at different places when the video is recaptured would imply that it is not caused by a defect on the tape.

Anti-virus programs can cause havoc with capture of a video stream from an IEEE1394 port, as can other software running in the background that may take occasional control of the PC for brief periods of time; e.g., and e-mail program that occasionallty checks for new mail.

FWIW some MiniDV camcorders allowed analog video input and could be used as a pass-through/conversion to a DV stream for capture via IEEE1394 port. This was model specific so you would have to check the documentation for your camcorder.
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Old 12-12-2013, 07:45 PM   #22
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Quote:
Originally Posted by dpalomaki View Post
FWIW some MiniDV camcorders allowed analog video input and could be used as a pass-through/conversion to a DV stream for capture via IEEE1394 port. This was model specific so you would have to check the documentation for your camcorder.
Same with some of the Digital8 models from Sony.
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Old 12-13-2013, 06:29 AM   #23
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My MiniDV camcorder does not have the pass through, I checked before I bought my Grass Valley device.

So right now I have Video on a tape that is in DV format, and that is digital. When it ends up on my computer it is an AVI. Does the conversation from DV to AVI happen in my computer through the use of the CPU? or in the camera?

Can I capture the video in DV format straight to my harddrive, then convert it to what format I want?

When I do VHS tapes will the conversation happen in my twinpact box? So the only thing the computer really does is record the converted file to the hard drive?
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Old 12-13-2013, 12:07 PM   #24
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And also some HDV camcorders; e.g., Canon HV20.
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Old 12-13-2013, 06:26 PM   #25
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Originally Posted by 2ball View Post
So right now I have Video on a tape that is in DV format, and that is digital. When it ends up on my computer it is an AVI. Does the conversation from DV to AVI happen in my computer through the use of the CPU? or in the camera?
AVI (DirectShow/Video for Windows) is a wrapper or container type. So is MOV (QuickTime).

The data inside is a specific compression format, in your case, DV.

DV can be store in an AVI, in a MOV, or just "unwrapped" as a raw DV file (usually .dv)

Capture over Firewire from a DV source is just a data transfer, and the optional wrapping. There is no compression or recompression. That's why it's very low-impact.
Type-2 DV AVIs (Video for Windows) will decode the audio and store an uncompressed copy in the AVI's audio track.
Type 1 DV AVIs (DirectShow) do not.
Except in rare cases, most software uses Type 1 DV AVIs now, so you shouldn't need to worry much about the distinction.

Quote:
Originally Posted by 2ball View Post
Can I capture the video in DV format straight to my harddrive, then convert it to what format I want?
Sure. Generally speaking, that's preferred over an on-the-fly transcode (decompression and recompression) as it leaves more CPU power available for the encoding and therefore can potentially produce better results.
It does take more time and storage space, though.

Quote:
Originally Posted by 2ball View Post
When I do VHS tapes will the conversation happen in my twinpact box?
Capturing analog through a DV converter like ADVC or TwinPact100 is done by hardware in the unit. No dependence on computer.
In fact, you could connect the TwinPact100 to your DV camcorder (in VTR mode) and capture from an analog source directly to DV tape over Firewire.

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Originally Posted by 2ball View Post
So the only thing the computer really does is record the converted file to the hard drive?
Yup. Elegantly simple. :)
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Old 12-18-2013, 04:19 PM   #26
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OK, So a had a hard drive failure last week. My internal 2t 5 year old storage drive (WD Green 5400rpm) would not be recognized. I disconnected it, moved it around and tapped on it. When I put it back in and hooked in up, it worked.

There is too much time and effort in archiving these tapes to risk a hard drive failure.

What is the recommended hard drive to use? I think I need a 3t drive. Does the drive have to be 7200 rpm or higher? WD and Seagate seem like good companies?
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Old 12-18-2013, 07:30 PM   #27
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Generally a 7200 RPM is recommended as the minimum for editing and reliable capture. I've found 5400 RPM drives to be a bit "iffy" on speed for capture and real-time editing purposes.

Serious editing folks tend to want a RAID 0 system (or better) for speed, but a many users find that modern 7200 drive is Ok if not trying to stream more than a couple files at a time.

Brand of drives? Which is best varies somewhat from year to year and the luck of the draw (was a specific drive a lemon). All makers appear to send out a batch of poor drives occasionally. Look at warranty and enterprise class drives are often a bit more robust (and expensive) than desk-top drives. Be sure to backup important material and heed warning signs than might hint at impending drive failure. I have no specific brand recommendation. (Heat is always a killer.)

Size of drives depends on your personal preference; big drives mean more data at your finger tips, and more to lose if the drive crashes.
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Old 12-18-2013, 07:32 PM   #28
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DV is only 25 Mbit/sec. That translates to 3.125 MB/sec, which is practically nothing for any drive from the past 7 years or so.

Also remember that you only need the speed/capacity for capture. Once the data has been captured, you can make copies on slower drives and media, like DVD-R (data, not DVD-Video), USB stick, or solid state cards.

If your concern is drive failure, a fault tolerant RAID system is advisable.
However, fault tolerance is still not a substitute for un-touched backup copies.
Fault tolerance alone does not protect you from malware, human error and other disasters.

At minimum, the rule of three, applies - 3 copies, 2 mediums, 1 off-site.

Here's a link that explains it more:
http://www.hanselman.com/blog/TheCom...leOfThree.aspx
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Old 01-03-2014, 06:07 AM   #29
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Thanks for all the info so far. I am getting everything together to convert my VHS tapes. My Twinpact arrived, brand new still in the plastic made in 2011. The seller charged my credit card wrong, so I got it for $22 including shipping, I feel like I won the lottery on that one. A hard drive is ordered and en-route.

I started working with my DV video. My dv video is from when it first came out i think its 720 X 480. I transferred the video to my harddrive. They looked crappy on my computer screen. They were grainy and they all have dark, places in the corners. I did not do any processing to them, I just picked the best clips and used nero to convert them to a dvd file, to be played on regular dvd machines.

When I played the clips on my dvd player through my 60 inch Led tv they looked great, not as grainy and no dark spots in the corner.

What is happening when I convert the AVI into a DVD file? Why does that improve the quality? or does it just seem like it does?
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Old 01-03-2014, 12:17 PM   #30
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A good up-scaling DVD player (or BD player) can make SD video look decent on a HD TV screen. Its not likely that the DVD conversion made the video better, but that the display system was designed for video, not computer graphics and text.

Computer monitors generally do not operate in the same color space as video, and they are designed for computer uses, not video uses. Thus they rarely give an accurate representation of what the video will really look like in a TV set environment. They may be set for high contrast that can make any vignetting and noise more apparent. Computer monitors generally do not overscan that hides the edges of the image making corner image flaws more visible.

FWIW: NTSC DV (and DVD) is just naturally 720x480.
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