Jim Uno emailed me, he said he was
a fan of my video's and he'd like to send me
some LED lamps because
they have so much better colour spectrum.
And, I'm always reluctant about taking on freebies,
but I knew I had a bit of a problem, because
shots at my table saw, this type of
Spruce wood always showed up a little bit green,
And, I always had to fudge the colours a bit,
to make it look good. Now, the LED lights,
that Jim sent me are mostly strips like this one.
But, I have a lot of light fixtures like this that I use,
so I also ended up buying some LED equivilant bulbs,
from the Home Depot. I thought I'd do a quick
check of the spectrum, just using a CD Rom
as a deflection grading and you can see how it
takes the light from the outside
and just, sort of, seperates that into different
colour bands, so I can see the individual wave lengths
on here quite nicely.
Now, let's check this with a lamp here,
and again, and this is interesting,
you can see here, there's different images
of this lamp with different colours.
So, that tells me this compact flourescent light
that I've got in here, is actually emitting
light primarily at very specific wavelengths.
So, I thought I'd set-up an experiment.
This is a compact flourescent bulb and this is
an LED bulb, and I want just a strip of light
exposed from each.
So, let's do the test with the CD ROM again.
And, looking at it here, on the right we have
the LED bulb, and on the left we have
the compact flourescent, and you can see the compact
flourescent has gotten most of the light
and just a few wavelengths
whereas the LED bulb is pretty smooth spectrum
in comparison. Now, Jim Uno says his LED's
are really good, so I've got one mounted on the ceiling.
And, let's try that again with the CD ROM.
And, there might be another peak with a blue as well.
Whatever it is, it's more like the other LED
and not lie the CF. So, I'm pretty sure
that the spectrum coming out of CF bulb,
is shit and the LED bulbs,
both Jims, and the ones from Home Depot
are way better. Now, to illustrate why the
spectrum difference is, even though we can't see them
with the naked eye, matter, let's switch to
black and white. So, we have these objects of
different brightnesses, and now I'm just gonna
switch lights, and you'll notice now
the brightnesses are quite different with respect
to each other. This had gotten way dark,
and this is quite light Let's switch back.
And, now if we look at the whole thing in colour,
it's obvious what the difference is, we're looking at it
with red light. So, the thing is,
the colours that we see as red, gree, or blue
are actually whole ranges of wave lengths.
And if the green from your lamp, for example, has only
one wave like the green, and the object is
very reflective or not at all reflective
at that wave length, the green will be much brighter
or much dimmer than it would be under natural light.
And, so what's causing this one to show up
slightly green, in many of my shots,
is probably that it's slightly more reflective at
the wave length that the CF bulbs emit,
than it is at other wave lengths, so if this
proportionally reflects green, when you illuminate it
with a CF bulb. The other nice thing about
LED bulbs is they're more efficient.
All three of these are 60 watt equivalant.
This one consumes 13 watts,
this one 10 1/2,
and this one just 9 watts. And, they're about the same
brightness. But, my understanding
is that bulbs like this are actually a relatively
poor match for LED's, because the LED's are best
when operated relatively cool
and if we look inside, this is the inside for
one of these, we have just eight LED's in here
and this bulb gets fairly hot
especially because we've got the whole plastic around here.
Whereas the strips that Jim sent me,
I've got this one long strip, this one is 12 watts,
and it's got 96 LED's and when it's on,
it barely gets warm. So, I set-up an experiment.
I've got the 13 watt CF bulb here,
and the 9 watt LED bulb here,
and as far as I can tell, these both have
a pretty equivilant light ouput, they're both 60 watt
equivilant. And, here I've got a
12 watt LED strip, but to be fair, I blocked off
one quarter of it, so it's like 9 watts of LED light
coming out. And, looking at it from
a distance, I'd say this is quite a bit brighter
than either of those two.
Given that these LED strips are more efficient than the bulb,
and I already have them, I went ahead and already
mounted some above my main work area, in the shop,
and the cool thing is these mount really flush to the ceiling,
so I'm much less likely to hit them,
but I still want to be able to control the light a bit,
so some of these I've actually put on swivel mounts,
so I can vary where they're aiming.
And, I'd like to also put one back here,
that I can either aim at the table saw,
or aim into the back of the shop,
so ideally I'd be able to have it out of my way, here,
or come down like this, here.
So, I need some kind of offset swivel for this.
So, I figure I'm gonna mount this LED strip on top of
this piece of wood, and then attach another short piece
on here and have an offset mount for the swivel.
So, I need to join the pieces of wood at the corner,
and, as usual, I'll use my screw advance box joint jig.
The light holder screws to this bracket that's
gonna mount to the ceiling and that allows it to
pivot around this screw.
The light strip has got this adhesive backing
and I'll just use that to attach it to my mount.
The LED lights, themselves, need to run at
a low voltage DC, and for that there's these
converters, here, and you can just plug the wires in here,
into the little terminal strip.
And, on the other side is line,
and I'll put my power cord directly in here.
I also keep forgetting to turn the lights off in the shop,
so, I've been experimenting with one of these motion
sensor switches. And, I've just wired it in
with a cable, and then that goes to
this lamp here. I can turn it on and off like
a regular light switch.
But, right now it's set to 30 seconds,
So, after 30 seconds of no motion,
it should shut itself off.
And, then when I come back in the shop,
it turns itself back on.
It's got these two little adjustable potentiometers
to adjust the motion sensitivity,
and how long it's gonna stay on, from 30 seconds
to 30 minutes. There's a couple of things
tricky about this one. It does need to have
ground hooked up to work at all, because it
actually drains a little bit of power from hot to ground,
just for it's own operational current, and the other thing,
for the first 30 seconds after power is supplied,
it won't do anything, it won't switch or anything,
and so it's almost like it's running Windows.
So, give it a bit of time, when you install it
and turn on the power.
And, now after I leave the shop, the lights always
turn off, and when I come back in,
they turn on automatically.
I love it.