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USB cameras:
use them with your smartphone
This review looks at a variety of USB cameras which are normally
intended for use with a laptop PC. But if you are trying to poke a USB
pipe inspection camera down a blocked drain you don’t want it to be
hooked up to a laptop – it is too awkward. The solution: hook it up to
your smartphone and use an app like CameraFi.
By Leo Simpson
I
have been eyeing off a couple
of USB pipe inspection cameras
from Jaycar for a while, as they
should be very useful in quite a range
of situations.
Jaycar have two models: one with
a 7-metre long flexible cable and one
with a 2.3m flexible cable but in other
respects they are identical. The camera
itself is only 10mm in diameter and
it can be poked into very small open46 Silicon Chip
ings indeed. And while it is billed as
a pipe inspection camera, it has far
more uses than that.
Incidentally, they are very often
described on the net as borescopes –
and even (obviously erroneously) as
endoscopes.
Since I was involved in a home renovation, there was quite of lot of wiring
and plumbing to be done and I found
that the electrician and plumber had
not even come across the idea of using a pipe camera for peering into wall
and ceiling cavities.
In fact, when running new cables,
most sparkies are using the tried and
true method of poking a strip of “yellow-tongue” into a cavity and seeing
if it can be fed through to the wanted
location. Often it can’t.
One particularly frustrating job involved installing a lot of LED downsiliconchip.com.au
We’ve shown this close-up of the 2.3m Jaycar QC3373 for
two reasons: you can see the four LEDs alongside the camera
lens, with brightness controlled by a knob on the box. Also
on the box is a “shutter” button to take a freeze-frame image.
lights in the this home and trying to
run the necessary cables over ceiling
joists was time-consuming and labourintensive. If the electrician had used
one of these inspection cameras, some
of the frustration could have undoubtedly been avoided.
But there are plenty of other applications where such a camera would
be very handy. For example, you
could use it check inside the cylinders of many engines (via the spark
plug holes).
It could possibly even be used to
check for corrosion and blockages
inside the water channels of exhaust
headers on boats.
Each camera incorporates its own
light source in the form of four white
LEDs, adjustable in brightness via a
tiny knob on the side of a small plastic
case in-line with the USB cable.
That same in-line box also has a
push-button which can use to take
photos or start and stop a video recording.
No batteries are required for the
camera since that comes via the USB
cable from the PC it is plugged into.
This one is the Jaycar QC3374 which has a the tiny (10mm
diameter) camera on the end of a rather stiff 7m cable. In this
case the control box is integrated with the USB plug. The mini
CD contains Windows software (but not Android).
OK, all good but there are many jobs
where you simply don’t want to have
a camera tethered to a PC.
Can you imagine a plumber trying to
inspect a pipe with this camera tethered to his laptop while he stands in
a muddy trench in the rain? Neither
could I.
But there is an easy solution. Ditch
the PC and use your smartphone instead. Virtually every tradesman has
a smartphone in his pocket and they
are always using their phone to take
picture of jobs. The pics can be used
for later reference or sent to clients.
And despite all the marketing hype,
trying to convince you otherwise, over
70% of smartphones sold in Australia
are of the Android variety (although it
must be said there are countless camera apps for iPhones as well).
So it is a simple step to hook one
of these inspection cameras up to the
micro USB socket on your phone. You
need an OTG USB female A plug to
micro male B plug.
By the way, OTG stands for “on the
go” and refers to adaptors while allow USB devices to connect to smartphones etc. Jaycar have a short cable
adaptor which will do the job (Cat
WC7747).
So that takes care of the physical
connection but would the USB inspection camera actually work in this
mode?
CameraFi
There are probably more camera
apps out there than you’ve had hot
breakfasts but one which we’ve previously used is CameraFi, a free Android
app from www.camerafi.com
So I duly downloaded the Camera-
Resolution
The camera has a resolution of 640
x 480 pixels and is quite adequate for
the tasks it is likely to be used for. Each
camera comes with Windows software
on a CD which can be loaded onto a
laptop PC (provided it has a CD or
DVD-ROM drive) and installation is
relatively straightforward.
You can then take the camera and
your laptop to the job to be inspected, poke the camera into the job and
view the cavity on the PC, take pics
or a video.
siliconchip.com.au
Here’s a screen grab of the CameraFi app from my Samsung smartphone. It
not only gives you instructions on connecting your camera (or in this case, the
inspection camera) but allows you to set various modes (including movie mode)
and a variety of other settings. It’s a free download from www.camerafi.com
May 2016 47
The proof of the pudding, as they say: this screen shot is
taken from the setting on page 46, looking down a large
stormwater pipe. You can even see the join in the pipe in
this shot – but fortunately, no blockages!
Fi app onto my Samsung Galaxy S4,
plugged in the inspection camera and
it worked first time. It’s just so much
more straightforward than loading
software from a CD into a laptop.
Well, does it work well as a camera in nooks and crannies? Well, yes,
sort of...
There are a few wrinkles. First, having the short OTG cable between the
camera’s USB plug and the phone is a
bit awkward, due to the relative stiffness of the camera’s cable.
I found it was better to use a compact rigid female USB to micro USB
adaptor.
Second, it is quite awkward trying to take a picture using the in-line
button on the camera cable. It is more
convenient to simply touch the camera
logo on the CameraFi screen.
The Samsung phone has a “speech”
function to take pics – you just say the
word “shoot” and it . . . shoots! But I
couldn’t get this to work with the app.
With a focus down to about 50mm (or even less) the camera
is more than capable of capturing text, which can then be
put through Optical Character Recognition (OCR) software
(also available online) and converted to a document file.
It would be ideal if the camera sat in
the centre of the pipe but it usually
doesn’t. It goes where it wants to go
– and in most cases, that’s following
an edge.
When you do get a clear view, it
works very well.
Other USB cameras
What about using CameraFi with
other USB cameras, such as a USB
microscope camera? I tried it with
Jaycar’s 5 megapixel USB microscope camera (Cat QC3199) which
we featured in the article on magnifiers in the September 2015 issue
(www.siliconchip.com.au/Issue/2015/
November/Magnifiers%3A+When+
You+Want+A+Really+Close-up+View).
Again, it worked really well and it’s
much more straightforward than using
it with a laptop or PC.
Selfie sticks
We cannot finish this article us-
ing smartphones without referring to
selfie sticks.
Most readers probably regard these
devices with disdain and think they
are only used by self-indulgent nitwits
to post images of themselves and their
equally inane transient companions on
Facebook or Instagram.
But selfie sticks can be very useful
devices when you are trying to look
into awkward locations which may
well be out of arm’s reach.
You only need to use a selfie stick
once in this sort of situation and it will
have already paid for itself.
By the way, if you do decide to
buy a selfie stick, make sure it will
“pair” with your phone (it’s a Bluetooth connection) before you make
the purchase.
There are quite a few which won’t
even find another Bluetooth device
and even some which won’t pair, especially if the smartphone is more
modern than the selfie stick
SC
Interpreting the image
But the biggest problem tends to be
when you are poking the camera down
a drain or in a wall cavity and trying
to interpret the image.
First of all, Murphy’s law ensures
that the image you see is not related
to the horizontal. It takes some brainpower to work out which way is “up”.
And the reason the image tends to
be “fuzzy” is that, especially when
you’re looking in a narrow pipe, say a
90mm storm water drain, the camera
will slide along the edge of the pipe.
48 Silicon Chip
A typical “selfie stick”,
fitted here with my Samsung S4
Android smartphone. The stick, which
telescopes out from about 90mm to almost one
metre, is supposed to “pair” with the phone via
Bluetooth to shoot pictures. . . except for one tiny detail –
it won’t! In my case, I simply take the photo by saying “shoot”
to the phone. But if your phone can’t do this, make sure you
buy a selfie stick that will pair with your smartphone! Inset top
left are two types of USB adaptors which are needed to fit an
inspection camera to a mobile phone.
siliconchip.com.au
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