crum@utah-cs.UUCP (Gary L. Crum) (01/01/87)
(I'm posting this here because it is (somewhat) relevant to the recent
discussions of direct computer to VCR animation production techniques, and
net.video seems to be rather dead at our site.)
Santa gave me a Sony SL-HF1000 for Christmas. It's a SuperBeta Hi-Fi VTR with
dual flying erase heads, probably the one that Mike Brenner was talking about.
According to the videotest in the December issue of Video magazine, its
suggested retail price is $1700. Typical retail prices are around $1400, and
the New York Camera mail order price is approximately $1100. I think that
its target market is the consumer, not the professional.
Here is my opinion: Even though it has dual flying erase heads, the SL-HF1000
is not appropriate for use as a single frame recording device. I've tried
using a number of different input video sources (including TV, camera, Amiga
and Atari computers), and recording frames at all of the VTR's recording
speeds with and without SuperBeta and Hi-Fi, but the results are all similar:
When played back, the animated scenes are not "stable"; the images "bounce" up
and down slightly. The edits can be virtually noise-free, however, thanks to
flying erase heads. If you know how I may be able to solve this vertical
stability problem, please tell me.
Besides twin flying erase heads, the SL-HF1000 offers a few other features
from the professional broadcast video domain. The unit includes:
o the RMT-148, a "multi-function Remote Commander" that has 59 buttons, two
switches, a "jog dial" and a "shuttle ring". Most of the VTR functions can
be controlled from this wireless (infra-red) remote control unit. Ten of
those 59 buttons are marked with the digits zero through nine, and can be
used for some data entry tasks, e.g., channel changing.
o a character generator that provides:
o title generation, featuring four character sizes, but providing
only white, monospaced characters (and not even in lower case!)
o on-screen information display of:
o tuner channel.
o time and date.
o tape counter (in hours, minutes, seconds, frames).
o timer programming information. Here, to allow the user to
select the date for automatic recording, the VTR displays the remaining days
of the current week and the days of the next two weeks in calendar format on
screen. An arrow cursor points to the selected day, and is moved around
using either the channel up/down buttons or the jog dial. Start and ending
record times are also displayed graphically while being selected, in
addition to being displayed numerically. Cute.
o playback/record speed and direction.
o automatic editing parameters like start and editing frame.
o 6.0 MHz "Super Hi-Band" recording in Beta Is mode. This gives about 300
"lines" horizontal resolution. Typical VHS HQ recorders (e.g., the Panasonic
1742) give 240 lines resolution in their SP mode.
o frame advance, normal/10, normal/5, normal, 2*normal, and "BetaScan"
playback speeds, all in both forward and reverse directions. The 2*normal
speed is not available in the Beta I mode. The RMT-148 has buttons for
each of these playback speeds, in addition to the jog dial and shuttle ring.
While in play mode, when the jog dial is moved slowly, each "step" of the jog
dial advances the tape one frame in the corresponding direction. At faster
constant rotation speeds, the jog dial caused the normal/10, normal/5, and
normal playback speeds to be entered. The shuttle ring is spring loaded, and
returns to the center (still-frame) position when released, otherwise, it
selects one of the available constant playback speeds. The jog dial can
also be used instead of the channel up/down buttons for information entry
such as channel changing, timer programming, and title background and size
selecting.
o TV channel add/erase for use with channel up/down buttons. Direct access
to non-selected channels is available from the remote.
o index signal set and searching functions.
o an integrated Sony RM-E100 editing controller, which helps provide:
o insert editing, where the user may mark starting and ending
insertion points.
o title insertion, either superimposed on the existing recorded
image or on a black screen.
o when connected to another SL-HF1000 (or possible other types,
providing that the needed synchronization and control connections
are available; the SL-HF1000 supports "Control S", "Control L", and
"Control T" protocols):
o automatic insert editing, where the playback start frame
on the "source" tape is marked, and the record start and end
frames on the "destination" tape are marked.
o automatic assemble editing, where up to eight desired
scenes of the original tape can be "assembled" onto another
tape successively and automatically.
o pre-roll editing. I'm not sure what makes this different
from automatic insert editing.
o butt editing.
o two RCA jack (NTSC composite) video inputs with corresponding stereo
audio inputs, in addition to RF (75 ohm) input and output.
o a line audio/video output, and a monitor audio/video output. The "data
screen" on-screen information is put onto only the monitor video output.
Most of the "data screen" information is also displayed on the VTR front
panel, albeit the tape counter there is accurate only to seconds.
o other things, like:
o quick-timer recording.
o tape return/tape return play.
o "Beta SkipScan".
o "frame-by-frame shooting". This is done by pressing the "RECORD"
button while the VTR is in record pause mode. This is not really
useful for animation, as these manual excerpts reveal:
"A very short recording of approximately seven frames will
be made and then the VCR will automatically go into the
pause mode again."
"The picture may be a little distorted and a noise may be
heard when the frame-by-frame recordings are played back
continuously."
For what it is worth, here is my SL-HF1000 bug/wish list: (Hey, is Sony on
this network?)
o The RMT-148, like the front panel, has a "REC MODE" button, but it works
only while programming the timer, and can't be used to remotely select the
recording speed otherwise.
o If "play" is pressed while the remote jog/shuttle capability is enabled,
the unit plays for an instant, then returns to pause mode. The second time
that the play button is pressed, play is sustained. Considering that the
jog/shuttle enable button causes pause mode to be entered when it is
pressed from play mode, this is almost understandable, but I think that
a better solution would be for the play button to deactivate jog/shuttle
mode all together.
o The numeric pad on the remote control unit cannot be used to enter data
like start and stop times while in timer programming mode.
o I would like a true "variable" playback speed range from -scan to +scan
speeds, just as the Sony U-matic recorders offer.
o A built-in SMPTE timecode generator would be nice. (A joke, of course.)
Well, that's my summary of the SL-HF1000. I don't have a Sony SL-HF750, but
that unit (which sells for much less, about $740 mail order) seems to have
all the nice features of the SL-HF1000 except for the "professional"
editing-related capabilities. The SL-HF750 includes the high band Beta Is
recording mode and the jog dial/shuttle ring combo on its remote. As I
mentioned before, there is a review of the SL-HF1000 in the December issue
of Video magazine.
"Needless to say," I highly recommend the Sony SL-HF1000, but I don't think
that it is "good" enough to put together animation directly from computer.
Of couse, it wasn't designed to be able to do that.
I use the unit primarily for watching the tennis strokes of Ivan Lendl, so I
can shape my strokes into his form. The availability of both forward and
reverse frame advance and playback speeds directly from playback pause mode
make it far superior for this purpose than any consumer VHS decks that I
have heard about (except for the Panasonic 1950, which is similar to the
SL-HF1000 but doesn't have a wireless remote or a counter accurate to
frames; someone please tell me if it is appropriate for use in a computer
animation system). The 6 MHz video bandwitdth Beta Is mode is also nice.
QUESTIONS FOR THE READER:
Do you understand the DT-1 video recording format? If it exists, and you
know about it, please explain it to me, or give me a reference. It it merely
a way to digitally sample and record NTSC composite signals, or does the
digital information represent the video frames as bitmaps? If it's the
latter, perhaps that format would be the best way to record frames in a
computer animation generation system.
Should I post another message describing my new Sony KV-2786R "digital
trinitron" TV and RCA VMT-400 "digital" VHS VTR? Both have picture-in-
picture and digital freeze, but I don't know if there's interest here.
(Boy, I should shut up before someone from the net breaks into my home and
steals all of this neat equipment. Well, I guess Salt Lake is far enough
away from most civilization to prevent that.)
"Not people; humpback WHALES!" - (paraphrased) Kirk, from STIV
[Gary] ({ihnp4,decvax}!utah-cs!crum, crum@cs.utah.edu)