The Bird Box
- Background
The box was constructed using a mixture
of 18mm external plywood and 18mm treated softwood. The roof has
been covered in roofing felt to help keep the water out for the
birds,
and for
the electrics. It was also painted black with non-toxic, low
odour water-based timber paint. Filming the birds coming and
going with a black background makes them stand out a little better.
Over the past 2 years we have used more
traditional type boxes which had false roofs to hide the overhead
camera in. We did also use some small cheaper surveillance type cameras,
but the quality was not brilliant. You can read about them and the
set-ups used for 2005 and 2006 here.
The box used in 2005:
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The box used in 2006:
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Like many people, we
have marveled at some of the shots that the BBC Springwatch team
produce, but trying to find out exactly how they do it proved impossible.
After hours of searching on the internet, all we could find were
various tidbits of information and much speculation from other people
on various forums.
It goes without saying that they would
have
access to a large budget and skilled people along with all the latest
technology and modern techniques. Maybe they should do a programme
to show everyone - just like David Attenborough does.
After watching some of the videos
again from the series, it seemed to us that they used a very bright
light inside, and used a glass wall. They appeared to hide the glass
panel well out of shot for most of the time, but if you pause a
few frames here and there, you can clearly see a camera or two lurking
behind what must have been a sheet of glass.
Using a glass wall in a bird box is nothing
new, we know a few people who have been successful using one, and
we did try it ourselves a couple of years back. The birds didn't
take
to
it
too well and the
problem
was that
the
lighting
over the nest area was reflecting off the glass (as there was a black
void behind it) giving it mirror like qualities. Birds are always
wary of reflections, and we only received a few visits that year
with no tenants for the nesting season.
We're hoping that we don't get a repeat
of that this year, and have installed another light on the other
side of the glass wall to hopefully balance
out and reduce the mirror effect
... why didn't the BBC appear to have this problem? (Maybe they used
special non-reflective glass?).
One inherent problem is also the fact that
the glass may become dirty over time. This may hamper image quality,
but we'll see how it goes.
If we don't get any nesting Blue Tits, we're
sorry, but we had to try!
The
Box for 2007
The design this year took many hours of experimentation,
given that we wanted to include a glass panel side,
three high resolution cameras, three microphones, and three different
lighting circuits with one being infra red so we can all see what
goes on at
night.
And fiddle we did! ... countless Sunday
afternoons were spent trying to work out what would hopefully be
the best solution. Every time we did something, something else changed.
Things kept happening,
such as we would get the right light angle for the overhead camera
and
fix everything
into
position, only to find later that one of the side cameras was picking
up too much glare on one of the wooden walls. Even when completed,
the overhead camera still had a reflection of light on the glass
near the floor, but it will get covered over (hopefully) when a nest
is built.
We won't bore you with all the details,
but we're glad it's done, and up in the garden now.
The hole in the front
is 25mm in diameter which is what the RSPB recommend for Blue Tits.
It is located facing North and hangs on a wooden wall surrounded
by Conifers and overhung by an Oak tree. About
20 metres away there are four more mature Oak trees where
caterpillars and grubs reside in abundance, and are favoured by
birds such as Blue Tits.
We haven't put a metal plate on the front
to deter predators, as last year this appeared to put off a few of
the birds at house hunting time. However, if trouble starts, then
we'll act accordingly.
The bird box mounted on the wall
in the garden:
The completed
box just before the roof was put on (click to here to
enlarge):
The Cameras,
Microphones and Lights
We use a total of four cameras, three inside the box and one mounted
externally. They are all exactly the same type and model,
and are day/night
cameras with Sony 1/3" CCDs producing a picture at 480 TV lines,
and can see down to 0.005 Lux.
This means that they see in colour
when there is enough light, and then switch to
black
and
white
mode when it gets dark.
By
installing
an
infra red
light
source inside the box, this allows them to pick up pictures during
the night hours.
They were bought from Hong Kong, and are
a fairly well unknown make:
The cameras have shielded 75ohm cable connected
to them, which in turn runs back to the house. They are all powered
by 12v transformers. Each was carefully positioned, and then fixed
into place with silicone sealant. This means we can happily pull
everything apart again if we wish to.
Different types of lenses are
used. The internal cameras all have F1.4, 3.5-8mm lenses fitted,
and the external one has a F1.6, 6-60mm lens.
Of course placing a camera so near to a
subject causes its own problems, as there is a very limited depth
of field to work with.
The other problem to contend with, is that
a nest will be built. This means that focus is very important,
as the subject will move over time. It's also nearly impossible
to re-focus a camera once the box is up in the garden, as we can't
exactly take a computer monitor out with us to see what is happening!
Trying out different lighting positions
(diagonally) ...
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... two side by side, but we settled for
just one in the end
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Anything from a marker pen ...
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... to a fluffy Blue Tit were used in testing
/ setting focus
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We also made up a focus sheet which was
placed at the bottom of the box, at the correct height to assist
with each camera angle:
You
can download a PDF of it here if
you wish to use it
Camera 1 - Overhead (fixed)
The focus has been set at 5cm from
the bottom of the box to allow for nesting material and the height
of the birds. This should allow a good 'helicopter' view of the nest,
eggs and chicks.
Camera 2 - Rear Side (fixed)
This has been raised up and focused down onto where the nest cup
will be made ... well, where we hope it will be made! Over the
past
2 years,
we made a note of where the depression was formed by the female,
and interestingly enough it was just about the same in both cases.
Let's hope she doesn't change her mind this year! Obviously, for
the reasons above, we'll probably only use this camera when she
has built the nest and starts to lay her eggs.
Camera 3 - Front Side (movable)
The focus and angle of this camera has been set to try and capture pictures
at eye level. Initially it will be raised only about 1 cm from the floor at
a
horizontal
angle. As
the
nest starts to be made, we'll add further height to it by inserting some pre-made
wooden packers underneath. Obviously this means opening the box to carry out
the maintenance, but we do assure you that we are very sensitive in our timings.
Generally as
a rule, you should leave a box well alone once it has some interest or tenants.
We certainly won't be going in there once the egg laying stage has arrived.
Camera 4 - External (fixed)
This is housed in a waterproof CCTV box and is focused onto the entrance hole.
At night all we see is an illuminated bird
box entrance, due to the infra red light inside:
As we wanted to record sound with each camera,
each has its own microphone attached. They are inline microphones,
which means they have Power In, Power Out and an Audio
Out connector. This saves on power supplies and allows the transformers
to plug into the microphones first, and then in turn they plug into
a camera. Each audio lead runs back to the house and plugs directly
into the Line-In port on the computers' sound card. They were bought
from RF
Concepts.
Inline Microphone:
Overhead camera - showing the light and
3 microphones:
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Overhead camera - back view:
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Daytime lighting is provided by low voltage
(12 volt) white LED deck lights. One sits directly above the nest
compartment, and the other sits the other side of the glass wall.
Both have separate
switches back in the house so they can be operated independently.
Last year we received a lot of emails about
what type of lights we used, so below are some pictures. They are
32mm Twilight deck lights made by Micromark. They give just
enough light, keep cool and give out a pure white light, rather
than discoloured (as can happen). We didn't want lights
that
got really
hot
incase a
bird decided to investigate! The reference number is MM70022. Web
Site link here.
10th March 2007- Update
The lighting from the two deck lights didn't actually prove to be
quite bright enough. What we hadn't allowed for was that the changing
direction and variance of daylight coming through the hole made
life difficult for the side camera.
As you can see below, the lighting was fine
when no light came through the entrance, but when it did, light walls
appeared. This gave a very pronounced light/dark effect on some of
the videos as the birds came and left.
Four low voltage LEDs with resistors were
introduced into the box to try and level the lighting conditions.
Infra red (IR) light is supplied by our
old trusty black and white camera from 2005. It's angled upwards
to help
disperse
the light, plugged into its own separate power supply and also
has a separate switch
inside
the
house. It's
not connected to take pictures, and we're only using it for
its IR light function. Birds cannot see this type of light, so to
them
it is completely dark at night.
Pro-240 IR light source (black box):
Altogether there are 12
cables coming back into the house, totaling 300 metres in length.
A schematic of the set-up
is shown below (click here to
enlarge).
Computer Hardware
and Software
In total we use three computers as follows:
1) For recording video from the inside
of the box / and uploading pictures to the WebCams
Dell Dimension
8100
1.3Ghz tower
PC
running Windows XP Professional installed with 640mb ram and 200gb hard disc.
2) For recording video from the
inside of the box / and uploading pictures to the WebCams
Dell Dimension 8100 1.3Ghz tower PC running Windows XP Professional installed
with 640mb ram and 200gb hard disc.
3) For recording video from the outside
camera / also used to put the web site together
Dell Dimension 8300 3.0Ghz tower PC running
Windows XP Professional installed with 1gb ram and one 200gb hard
disc and another 300gb hard disc.
Given that there are three cameras inside
the box, and only two computers to take pictures with, the video
leads are simply switched between the two machines to record whichever
view
is required.
At the height
of
the
season (when there is continual movement inside the box) the
internal cameras can produce a lot of data, and 200gb fills
up quickly. We also find that it is well worth defragmenting the
hard discs once a week to keep them in optimal working order.
The video cables from each camera are plugged
directly into Hauppauge 1300 HVR PCI cards.
We have used PCI DVR cards in previous years, but these have been
a bit sluggish at times. Utilizing the Composite Video In port on
the card means we achieve a better rate at around 25 frames per second,
although for some reason this does seem to fluctuate between 17fps
and 25fps at times. All computers
are fitted with exactly the same type of card.
Hauppauge 1300 HVR PCI Card
To make sure that all the computers have identical date and time
stamps, they have a piece of software called Atomic
Clock Sync installed.
This neat free utility synchronises each computer via the internet
each day, and also does it again if a computer is restarted. However,
even doing this, we still end up with minimal
differences in time between each of the three machines.
Why is time accuracy so important? Well,
when we put the videos together that are shown in the diary pages,
the camera angle quite often changes throughout the clip. We rely
heavily upon the time stamp to marry up the different camera angles.
After a bit of searching and testing, we
settled on Active
WebCam to use as our recording and monitoring software. It
has it's faults, but after having now
tried over 12 different vendors, we're sticking with it again
for 2007. It just seems the most flexible of the bunch.
The software is set up to detect any motion
that a camera might record, and when it does, a movie file is recorded
to disc. Given that we are not around all the time, it's a great
way to catch up with the days' proceedings.
This is how we see the cameras on
the computer screens
Active WebCam is quite reliable, but a bit
of a memory hog and can crash on the odd occasion. The way round
this
is to configure the software to restart the computer if it locks
up. Thankfully they include this feature in the programme, so it
really does look
after itself.
As we are prone to power cuts, especially
during the Winter months, all of the computers are configured
to automatically switch back on in the event of a power outage. Hopefully
this means that the WebCams restart again without our intervention.
We've also fitted a surge protector to the 240v supply to the box,
just incase the cameras get power spiked.
The Web Site is authored and maintained
using Macromedia Dreamweaver MX. Miscellaneous pictures are taken
with
Canon digital cameras (A40 and EOS 350D) and are processed for the
Web Site using Adobe PhotoShop CS2.
The graphs and weather charts are put together
in Microsoft Excel and exported into PhotoShop before being used
as
jpeg images
within
the site.
All the movies are converted for broadband
viewing using Microsoft Movie Maker 2.
WebCam
Every 7 seconds* Active WebCam takes a snapshot and uploads it to the
Web Server via our broadband line. The WebCam page refreshes every
10 seconds. By uploading a new picture every 7 seconds, we hopefully
eliminate the possibility of a viewer seeing the same picture twice
or seeing a blank screen.
* Upload times are increased as the season
progresses to allow a quicker refresh rate.
Weather Station
The data that we enter into the weather
graphs is recorded on a weather station inside the house. It has
a remote sensor which is located outside. Each morning the unit
is polled for the previous days' readings and then reset.
It would be great if the station plugged directly
into a computer and automatically wrote the readings to disc, but
those sort of systems are still very expensive.
Master unit inside the house:
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External sensor outside:
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Please Note
We do not specifically recommend any of the items mentioned on this
page.
They have worked for us and our set-up, and should you be
considering using any of the above mentioned equipment/materials, we
cannot be held responsible for any problems that may arise.
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