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HIDs:
out of the car and
over your shoulder!
by Ross Tester
It’s taken a while but at last, High Intensity Discharge (HID) lamps
are starting to appear in places other than just in car headlights.
Y
ou must have noticed them as you drive along: along- two facts alone mean they are much more efficient. But
side a conventional car headlight (ie, filament type they also offer significantly longer life (3000 vs 700-1000
and probably of the tungsten-halogen variety) they hours) and studies have shown they actually make night
look positively blue – or is it that even tungsten-halogen driving safer.
For an explanation on how HIDs work, refer to the articles
lamps look quite yellow alongside them?
More recently, HID lamps have started to filter down to in our February 1999 and/or May 2003 issues
the more mundane type of vehicle, although it’s true to say
that even today they are not as popular as tungsten-halogen HID Spotlights
We wondered how long it would be before HID lamps
lamps as original equipment. That’s almost certainly because of cost, where auto manufacturers look to save every started making inroads into “hand-held” spotlights. We
say hand-held with a grain of
cent possible.
salt (or perhaps a full shaker!).
In the auto accessory stores,
The ones we are talking about
HID replacement kits have also
are more “luggable” than handstarted to make their presence
held – which is why they invarifelt, even if at a premimum
ably have a shoulder strap! You
over “normal” lamps. Still, the
know, the type of spotlights you
margin between the two is eversee in your local auto accesdecreasing.
sory store offering “a million”
For those who have been
candlepower – or maybe even
driving around with their eyes
ten million candlepower. When
closed, HID lamps offer several
you’re talking those numbers,
advantages. For a start, they are
who is going to argue?
brighter. At the same time, they
Just think, though, how much
require less energy from the There’s no denying it’s a HID! Jaycar were never ones
light ten million candles would
car’s electrical system. These to hide their light under a bushel . . . (ouch!)
16 Silicon Chip
siliconchip.com.au
produce. A tad more than one of these spotlights? Yeah, we
think so too! By the way, 1 lumen roughly equates to 12.57
candlepower, so does one of these “ten million” babies
put out more than 795,000 lumens (10,000,000/12.57)?
Hmmm . . . maybe not!
However, this type of spotlight is very bright and is ideal
for, camping, 4WD’ing, nocturnal animal observation/hunting and so on. They are also used by emergency services,
police and rescue organisations, etc.
But we digress: a recent SILICON CHIP advert for
Jay-car Electronics got our attention when it claimed
to be the first spotlight with a HID lamp. This we just
had to see.
So as soon as stock actually arrived in the country,
Jaycar Electronics sent us one to examine. It arrived
with the battery already charged so we were able to use
it immediately.
Incidentally, the rechargeable battery gives about 50
minutes of continuous use and it recharges either from
a mains plugpack or a car cigarette lighter lead, both of
which are supplied. It weighs in at a rather hefty 3.8kg so
the comments we made before about luggability certainly
apply.
First impressions count – and to say we were impressed
is an understatement. Yes, it had a very bright, very blue/
white light – just like the automotive versions. In fact,
it hurt to look into the beam (but no-one would be silly
enough to do that, would they?).
Fortunately, we had one of those mega-candlepower
quartz/halogen spotlights with which to do a direct comparison. It’s an Arlec RT10000 which we bought a year
or so ago from a local auto parts shop. Apart from being
bright yellow (the Jaycar one is basic black!) the two were
quite similar in size and weight. We’d always been pretty
impressed with its performance – especially its brightness.
It was great to take camping!
Well, the HID model from Jaycar appeared much better.
What’s more, it appeared to have a more focuss ed beam so
it was even better at lighting up distant objects. Subjective
reaction was fine – but could we confirm it?
Part of the photographic setup at SILICON CHIP includes a
very accurate Minolta Flash Meter – we use it to measure
the output of our studio strobe during photography settings. This meter (fortunately!) also includes an
“ambient light” setting – in other words, you
can measure the amount of light falling
on a subject without flash. And
our experience is that it is
dead accurate.
Placing the light meter at
a set distance from each of
the two spotlights, we found
that the HID model was exactly one f-stop brighter than the
quartz halogen model.
For those not into photography,
the difference between any
two f-stops is double or half
the amount of light. So instead
of a subjective “yes the HID is
brighter” we could now confirm
it was twice as bright!
Power consumption
was also significantly
lower with the
Jaycar
HID,
as you
would expect. It was rated at
35W, whereas the Arlec has a Philips H4 halogen lamp
rated at 100W – virtually three times the current draw
from the 12V, 7Ah battery.
Which one would we choose?
Just on light levels alone, we’d choose the HID model
over the quartz halogen model any time. Except for one
tiny detail: the HID models are also about twice the price.
Our Arlec spottie sells at the local Super Cheap Auto store
for about $89.00 (every now and then it’s on special, save
10%). The Jaycar ST-3369 HID Spotlight sells for $165. So
for twice as bright, you’ll pay nearly twice as much.
Actual rated output of the Jaycar HID model is 3300
lumens, or 262 candlepower. It just goes to show how
ludicrous the claims of those ten million candlepower
spotties really are!
Is it worth the extra?
Obviously, that depends on your application and whether
you need the performance. But for our purposes, we would
suggest that the HID model gives you so much more that it
is well worth paying the premium that it commands. SC
Jaycar Rechargeable 35W HID spotlight (Cat ST-3369)
–$165 at all Jaycar Electronics stores
This photo shows the
actual HID bulb in the
Jaycar ST-3369 HID
Spotlight.
A typical HID bulb
showing its construction.
siliconchip.com.au
May 2009 17
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