From: mullen@itd.nrl.navy.mil (Preston Mullen)
Subject: various TR101 observations and questions 
Keywords: TR101 camcorder
Reply-To: mullen@itd.nrl.navy.mil
Organization: Information Technology Division, Naval Research Laboratory
Date: Tue, 17 Nov 1992 03:22:11 GMT

Note, the following all actually apply to a Nikon VN750, but
since it's the same as the Sony TR101, I will use TR101 below.

1.  The Data Code feature is very convenient.  The camera always
    records date and time, and you can decide at playback time
    whether you want to see it.  (Terry Quinn mentioned in a recent
    post that the data code is passed over the LANC interface.)
    You can also "burn in" date or time in the usual manner when
    recording, but there seems to be little reason to permanently
    deface the video when you can select the Data Code on playback.

    Questions: How common is this feature on camcorders and Hi8 decks,
    including "professional" models like EVW-300 and EVO-9850?  How is
    it implemented, i.e., where on the tape is the data code written?

2.  Can anyone surmise why this camcorder can write RC time code but
    not read it?  Does anyone know how the RC time code is derived?
    Is it based on the Data Code (current time) or does it just
    start with 0 at the beginning of the tape and count frames?
    Is it drop frame or non-drop-frame?

3.  When the tiny infrared remote control is used within the camera's
    field of view, a flashing light is picked up by the camera (at
    least in low light situations).  It's quite distracting, although
    it makes a nifty sci-fi special effect.  I can't see any light
    coming from the control when I look into the business end and push
    the buttons.

    Questions: Why does this happen?  Is the remote control really that
    bright in infrared, or is the apparent brightness an artifact of
    the CCD's response?  Can anyone quantify the brightness and
    wavelength of a typical IR remote control and relate that to IR
    emissions from warm bodies?

4.  On playback into a computer with video-in-a-window capability
    (specifically, a NeXTDimension board), I saw a tearing (bending)
    of the image at the very bottom.  This is with an application that
    doesn't crop the image; another one effectively overscans and
    doesn't show this tearing; it doesn't show up on a normal TV
    monitor either.  I haven't tried it with a TV monitor that can
    underscan, but I'd bet it would show up there.
 
    Question: is this normal or is the camcorder defective, e.g. not
    tracking exactly right?  Do all VCRs do this in what is normally
    outside the safe area?  Why?
 
5.  Dropouts.  With a relatively small sample of TDK ME-120 tape,
    tape, I've seen more dropouts than I'd expected (mostly the part-of-
    one-scan-line-flashing-in-one-field variety).  They range from one
    every 30 seconds or so to several in that time.  They seem more
    prevalent near the start of a tape.  I also notice an occasional
    glitch that looks like a ripple or bump that sort of rolls up the
    screen, which I assume is some problem that crosses more than one
    helical track on the tape.  Finally, the entire image has
    something about it, I don't know exactly how to describe it, sort
    of a vague artificiality or shimmering, almost as if the frames
    were slightly delayed now and then, or digitally processed in a
    not-quite-transparent manner; not like normal video you see over
    the air or anything I've seen in the past from old VHS camcorders.
    It kind of reminds me of some satellite broadcasts that were (I
    suppose) converted from PAL.  But this is a very subtle effect; the
    video is still quite good, but at the worst moments, the combination
    of all this does distract slightly from the program.

    Questions:  Any idea what this last effect could be?  Is it
    characteristic of all 8mm or Hi8 (or other) camcorders?  Also, does
    anyone have a surefire source of dropout-free Hi8 tape?  Is there
    any practical difference between MP and ME tape in terms of wear
    and tear on the machine, suitability for later editing, etc.?  Is
    there any way a camcorder problem could contribute to any of these
    effects, especially the last one?  Could it actually be an artifact
    of the image processing that supposedly goes on in the TR101, or a
    defective instance thereof?

6.  Scenes seem to have a bit too much color saturation upon playback;
    this is especially noticeable in the reds.  If I back off the color
    control a little on the TV, the activity in the reds settles down
    and everything looks more like it did in real life.  So, why would
    the color level be higher than broadcast TV, an old VHS VCR, etc.?
    Can this be adjusted or fixed, or is it just a characteristic of
    TR101 or Sony camcorders or Hi8 in general?  Why do reds tend to
    be more vibrant (in an unnatural way) than other colors?  Is this
    a characteristic of Sony TVs (KV20EXR10 using S-video input) or of
    NTSC itself?