All tape media are subject to "dropouts" (the failure to
record on a part of the tape due usually to obstructions
like dust, defects, etc.). With Mini-DV, there is a very
good concealment system, so unless you are sensitive to
small out-of-place parts of the image with motion (small
dropouts are covered with material copied from the previous
frame, so all you see is a minor displacement of a small
area unless the dropout is major - then bands, blocks, or
other quite noticeable artifacts show...), you may not
see the minor dropouts. With a clean camera and fresh
Mini-DV tape, you should see no major dropouts in a tape,
even with many playings and several recordings, and probably
no minor ones, at least on the first few recording passes...

On Sat, 11 May 2002 14:11:57 GMT, John Smith <6g8nc2e001@sneakemail.com> wrote:
>
>Thanks for the info. However, can you please explain what is a
>'dropout rate'?

>d_ruether@hotmail.com (Neuman - Ruether) wrote:
>:On Sat, 11 May 2002 03:34:09 GMT, John Smith
>:<6g8nc2e001@sneakemail.com> wrote:
>:
>:>Can someone tell me the difference between the three different types
>:>of Sony MiniDV tapes: EXM, EX2, and PR? I've heard not very good
>:>things about PR, but what's the difference between EXM and EX2?
>:
>:The EX supposedly has a 2db S/N advantage compared with PR,
>:invisible on recordings, but perhaps useful with long-term
>:storage; the chip in the EXM is for most a useless extra
>:expense. All are excellent tapes.
>:
>:>Also, is it okay to re-use MiniDV tapes (tape over previous video)?
>:
>:Yes.
>:
>:>How many times can one do this before wearing out the tape?
>:
>:MANY times. The limit is reached when the dropout rate
>:becomes unacceptable to you...
>:
>:>And since
>:>I am using a Sony camcorder (TRV27), should I even consider using
>:>other brands of tape (Fuji, Panasonic)?
>:
>:Use any tape you can get easily and reliably, but once
>:you start with a tape, DO NOT CHANGE TAPE BRANDS!!!
>:Incompatibilities in lubricants *can* cause problems,
>:though some report that if the tape brands are mixed
>:often enough, problems are minimal (or those who do
>:this don't notice the higher rate of minor dropouts,
>:if any...). There is no manufacturers' info on this,
>:but the reporting here has, over a long time, indicated
>:a problem with tape brand mixing - though most brands
>:are made by either Sony or Panasonic, so mixing *some*
>:brands may not really be a problem as a result. I don't
>:know who makes what brands, so I never mix brands
>:at all. (This is for Mini-DV tape only...)
>:David Ruether