capture trouble

5 replies [Last post]
ptbarney
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Joined: Aug 6 2003

Hi. I use dv.now.av. With windows xp. When I capture using rca cables it works fine. When I capture using the IEEE 1394 cable, it stops recording after a few minutes.

I capture on the fly. When I use rca cables I hit play on the camcorder and record on dv.now.av. No problems.

Unfortunately my new camera doesn't have rca outputs. Any thoughts would be greatly appreaciated.

Thanks

Dave R Smith
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Joined: May 10 2005

Some pc's have a 2 gig file size limit - which I believe is true when on a FAT32 system.
When you capture via RCA it's possible your software/hardware is compressing it to save to file (via avi codec or to mpg?), so the 2 gig limit isn't broken.
When using firewire it takes about 4.5 mins per gig, so would stop around 9 or 10 mins?
Do you have any rca captured files previously over 2 gig?
The obvious - you do have 'free' space on your pc?

This may be a red herring - but worth checking.

Dave.

ptbarney
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Joined: Aug 6 2003

Thanks for the reply. It stops capturing after about 3 mins. Sometimes more. Sometimes less. I have lots of hard drive room. When I used my rca cables, I was able to capture 3 one hour tapes in a row with no problem at all.

I was wondering if maybe it stops automatically because of dropped frames. I thought there was an option somehwere to make it capture regardless of dropped frames. Can't seem to find that option though.

Thanks again

dpalomaki
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Joined: Jan 2 2001

Note that the 2 GB limit on firewire capture with FAT32 also applies to capture via RCA or S-VIDEO input. File size will be the same. Check the options in FF to see if they have changed. You can set FF to split long captures into multiple files automatically.

If IEEE 1394 (FireWire) capture fails occasioanlly, especially if at the same spot on the tape each time, while analog capture succeeds, it may be due to a drop out or other uncorrected tape read error. This error is seen as an brief interruption in 1394 the data stream and capture aborts at that point. One apprach is to resume capture at the point of failure and then splice the tape when editinig.

If RCA capture works OK, so should capture via the S-VIDEO, which should result in better capture quality than RCA, approaching direct firewire capture.

Dave R Smith
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Joined: May 10 2005

Quote
>>> Note that the 2 GB limit on firewire capture with FAT32 also applies to capture via RCA or S-VIDEO input. File size will be the same. Check the options in FF to see if they have changed.
>>>
It doesn't seem to be ptbarneys issue, but RCA/s-video files sizes can be alot smaller than firewire.
For example on my old system using Premiere 5.1, compression settings could be set for capture which meant a much smaller file size.
More recent software - like Premiere Pro - is 'firewire' only, so RCA/s-video has to go through an analog/digital convertor - so ends up the same size. This is presumably what you had in mind.

For dropped frames - I recall another thread about this around 10 days ago, where someone was getting fed up with it. I think the solution was different software to 'skip past' these frames - but can't find the thread at the moment.

Dave.

dpalomaki
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Joined: Jan 2 2001

To be more specific. FAT32 file size limit is 4 GB, but AVI files in Video for Windows format (the common type) are (or at least were) limited to 2 GB, with out regard for the file system.

DV.now AV uses DIF as its native format, and will support up to 4 GB on FAT32, or larger on NTFS ststems.

I believe that you will find that the standard DV data stream is specified at ~25 Mb/sec, regardless of the source of the capture format. Thus if one uses the DV standard (used by DV.now AV), the data rate (and file size) will be the same whether it is captured from a composite, s-video, or IEEE1394 stream. However, if one uses a different compresed video standard (e.g., MPG2), the file size will be different, and more subject to variations caused by variations in video content/bandwidth.

http://neuron2.net/LVG/filesize.html is a reference.