Rattled by Hum
Thanks to Mike Loehr for his Edit Suite column "Choosing an Audio
Mixer" in the February 1997 issue of Videomaker.
I am a social worker who uses video as a tool to offer barrio youth some
alternatives to drugs and violence.We have a Panasonic 456A camcorder that
seems to work fairly well. My problem has been in using multiple external
microphones. The Shure audio mixer we have seemed to be too powerful for
this camera. I tried using low-impedance jacks and high-impedance jacks,
but I’d always get a loud hum. This hum forced us to use only one mike at
a time, which prevented us from having panel discussions.
The various audio/video dealers I had spoken to had no idea what was
wrong. I even sent the camera back to Panasonic for a diagnosis. Needless
to say, they found nothing wrong with the camera. Then I read Mr. Loehr’s
article. In it he explained that mikes are low-level and that other sources–like
CD players or tape decks–are high-level (line-level). This caused me to
think that maybe what I needed to do was to plug an attenuator between the
mixer’s line-level output and the camera’s low-level mike input. I tried
this and it worked. I was able to use the mixer and four mikes with no humming
whatsoever. Thanks for helping me solve this problem.
Manhattan, New York
Where’s Manual Zoom?
Your "Buying a Camcorder" Buyers Guide (December 1996) didn’t
list one of the most important characteristics of a video camera: manual
Manual zoom is necessary to do a quick focus and to do variable-speed
zooms for effects during shooting. I cannot work an active shoot without
manual zoom because auto focus is not accurate in cluttered scenes and auto
zoom is not fast enough to use for focusing.
Please, in future buyers guides, score manual zoom. Thanks.
8mm vs. Hi8 as Master
You mention in your December article "Buying a Camcorder" that
8mm tape can be recorded on VHS tape but will lose some sound and picture
quality. If such a transfer were made with Hi8 tape instead of regular 8mm,
would it have better quality?
Any time you copy an analog video or audio signal from one tape
machine to another, the signal will experience some degradation, called
generation loss.However, some analog formats suffer less generation loss
than others.The rule of thumb is: the better the format you record on, the
less generation loss your copy will suffer. Since Hi8 is a better format
than regular 8mm,a signal recorded on a Hi8 machine would fare better than
a signal recorded on an 8mm machine when copied onto a VHS machine.
But your question is slightly unclear. You ask, "If such a transfer
were made with Hi8 tape…." If by that you mean a Hi8 tape recorded
on a Hi8 camcorder or VCR, the answer to your question is yes. However,
if you mean a Hi8 tape recorded on a regular 8mm camcorder or VCR (which
is possible but is a waste of money), the answer is no.The tape itself will
make no difference; it’s the signal recorded by the Hi8 machine that makes
I have been watching your magazine and others closely for a buyer’s guide
or some other kind of price-to-product analysis of video projectors.
It seems to me that the video-projector field is being totally ignored
by your magazine and others. Video projectors have come a long way in the
past few years. I see them used at seminars and other presentations, and
the quality of the image is exceptionally good in most instances.
I would very much like to see an article on these units that would cover
everything from the "el-cheapo" to the more sophisticated models.
Wisconsin Rapids, Wisconsin
Sorry, Paul. The only video display devices we cover are small- and
medium-size video monitors because our readers use them to edit their videos.
As you state in your letter, video projectors are used to display video
to goups of people in classrooms, seminars and other presentations. Videomaker
Magazine is geared primarily toward people who use camcorders, VCRs and
other video-production equipment. In other words, we cater to those who
make videos, not those who present them.
In our feature on music and sound-effect libraries (January 1997), we
incorrectly reported that QCCS has a nine-volume music library. The company
actually has a 20-volume collection. Each volume is available for $59, or
$40 each if you purchase the entire set. You can reach QCCS by telephone
at (541) 345-0212 or visit their Web site at http://www.PBTM.com.