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-   -   Sony HDV Tape stock question (https://www.dvinfo.net/forum/long-black-line/475888-sony-hdv-tape-stock-question.html)

Colin McDonald April 1st, 2010 02:09 PM

So you found your Brazilian a bit painful did you Shaun? :-)

I'm with you on the JVCPro HD tapes though they can be a bit hard to find over here.
I still use the JVC-DV60DE tapes on Standard Def jobs.

I'm interested in what you said about MPEG problems - can you explain explain more?

Shaun Roemich April 1st, 2010 02:32 PM

Quote:

Originally Posted by Colin McDonald (Post 1508610)
I'm interested in what you said about MPEG problems - can you explain explain more?

A lot of the issues I have found with capturing material from Sony and JVC HDV cameras alike that Final Cut Pro reports as timecode breaks are more related to the long GOP MPEG stream not being closed properly at start/stop points (and with Sony ESPECIALLY at points where the pause was long enough for the head drum assembly to "spin down") and not from REAL drop outs which can be typically characterized by a pixelization of material during playback.

Colin McDonald April 3rd, 2010 01:50 PM

Shaun, does the video play back OK on the cameras' LCDs when FCP reports these capture problems ?

I know it's hard to say without actually seeing them, but I've been assuming that occasional "dropouts" characterised by an approx 1 sec image freeze (no pixellation) are dirty head/tape quality issues. Cameras involved are all canon HV-30s. What do you think?

Shaun Roemich April 3rd, 2010 02:14 PM

Colin:

The errors I'm talking about indeed play back normally. My thoughts on the image freeze are mere speculation: it may depend on whether the camera has error suppression logic built in to deal with dropouts (like the blue screen that comes up on VCRs when there is no signal, for example). A freeze also SEEMS like the sort of thing that would come from an improperly closed MPEG stream as the decoder would need an "i frame" to begin playback again after a corrupt MPEG stream and then due to the GOP, it should take half a second before it sees the next "i frame".

Again, mere speculation based of educated guesses here. All I can offer.

J. Stephen McDonald April 10th, 2010 03:52 AM

I used the best HDV tapes for awhile, then discovered that the cheapest type that Sony makes, really are "premium". I have had no glitches with them so far and a few have been used for utility clip re-recording, a dozen times or so. At 3 bucks or less a pop, I'm not going to complain about having to pay so little.

It may actually be like the contact lens scandal. One company was selling the kind that can be used continually, in three quality-levels and prices. Then, it was revealed that the $100. type that lasted a year, was exactly the same as the $25. ones, that were rated for only a month.

Shaun Roemich April 10th, 2010 02:48 PM

Quote:

Originally Posted by J. Stephen McDonald (Post 1512448)
It may actually be like the contact lens scandal. One company was selling the kind that can be used continually, in three quality-levels and prices. Then, it was revealed that the $100. type that lasted a year, was exactly the same as the $25. ones, that were rated for only a month.

I know that at ONE point, Sony differentiated quality of tape stock by WHERE in the wide path of manufacturing the stock was cut from - the centre cuts were Broadcast or Master grade while the outer cuts were sold as "regular" tape stock.

I remember seeing a Sony Broadcast poster explaining the difference with their premium HDV stock as having higher magnetic potential and a better base layer so that stretching and long term storage SHOULD have less effect.


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