From Garrett:
Whats Behind Us?By Garrett LambertRecreational vehicles are often described as land yachts because they share so manyattributes with their sea-going brethren. One of them is unfortunate: poor visibility when
reversing. On the other hand, when RVs stop, they stay stopped. Boats never stop, they just
drift in a different direction.
Technology to the rescue.The explosion in security and safety concerns over the past decade has produced a flood ofnew and inexpensive closed circuit television (CCTV) equipment. The passenger car business
has been quick to adopt and adapt - Infiniti now has a system providing 360° views - and the
after-market sector provides consumers with a lot of choice.
RV drivers were quick to mount CCTV systems on their rigs to guide them when backing up.
However, boaters seem to have been slow to recognize the benefits of being able to see the
back end of the boat and beyond, monitor a towed dinghy, or, with extra cameras, check on
engine room gauges or other areas of the vessel.
After some Internet research, and visits to RV dealers and major electronics outlets, the first
conclusion I reached is that almost any of the systems on offer is better than having none, but a
few stand out as superior. I know some boaters who are proponents of wireless car licence
plate kits, but thats primarily because of prices well below $100. However, licence plate
camera optics are designed for close-ups, and the 2 ½ monitors become difficult to interpret
with a big picture on the screen. For our needs, they also require optional wide-angle lenses
that push the price up and the image quality down.
Photo 1
Single and multi-camera security kits are readily available, but the cheap ones tend to be flimsy
particularly the all-important mounts and detailed performance specifications are few and far
between. The few reviews Ive found tend to be disparaging. And, while good quality security
cameras probably offer the best choice and value for multiple camera installations, the cameras
are often bulky and the kits are usually packaged with recorders rather than monitors.
Issues to ConsiderMy search for decent quality equipment suited to the particular circumstances of a boat found<font face="Arial" size="3"><font face="Arial" size="3"></font>the Winsted Group at</font><font face="Arial" size="3"></font>*
www.rearviewcamera.net. This website is uniquely rich in essentialinformation for anyone considering this purchase, and includes a chart comparing its Provixsystem to others. In fact, it was the only one I found that provided complete and detailed
specifications for all components.
<font face="Arial,Bold" size="3"><font face="Arial,Bold" size="3"></font>WIRED OR WIRELESS:</font><font face="Arial,Bold" size="3"></font>**
<font face="Arial,Bold" size="3"><font face="Arial,Bold" size="3"></font>FIELD OF VIEW:</font><font face="Arial,Bold" size="3"></font>**
HorizontalLens AngleWidth
5 feet
from
lens
Width
10 feet
from
lens
Width
25 feet
from
lens
Width
50 feet
from
lens
Width
100 feet
from lens
fish-eye
Diagonal
Lens Angle
Lens
Size
42° 4 ft 8 ft 19 ft 38 ft 77 ft None 53° 1/360° 6 ft 12 ft 29 ft 58 ft 115 ft Minimal 75° 1/3
90° 10 ft 20 ft 50 ft 100 ft 200 ft Slight 106° 1/3
95° 11 ft 22 ft 55 ft 11 ft 222 ft Slight ° 1/3
100° 12 ft 24 ft 60 ft 119 ft 238 ft Yes 115° 1/3
110°
(standard)
14 ft 29 ft 71 ft 143 ft 286 ft Yes 123° 1/3
130° 22 ft 43 ft 107 ft 214 ft 429 ft Strong ° 1/3
150° 37 ft 75 ft 187 ft 373 ft 746 ft Extreme ° 1/3
<font face="Arial,Bold" size="3"><font face="Arial,Bold" size="3"></font>THE CAMERA:</font><font face="Arial,Bold" size="3"></font>**
<font face="Arial,Bold" size="3"><font face="Arial,Bold" size="3"></font>THE MONITOR:</font><font face="Arial,Bold" size="3"></font>**
Sidebar/FootnoteIPX criteria are prescribed by the International Electrotechnical Commission establishedin 1906. The IEC has set 8 levels of performance for challenging operating conditions.
IPX1 requires protection against water drips, while IPX8 requires protection for full-time
underwater operation in depths greater than 1 meter.
IPX6 states: [The appliance must tolerate] Water projected at all angles through a
12.5mm, (0.5 inch), nozzle at a flow rate of 100 liters/min, (26.4 gpm), at a pressure of
100kN/m2, (14.5 psi), for 3 minutes from a distance of 3 meters.
The monitors backlighting, resolution, and refresh rates should be sufficient toprovide a clear, no-flicker picture in daylight, and the screen should be large enough to enabledetails in that picture to be readily discernable from the helm. While a monochrome image
would do the job, color helps to distinguish detail. The monitor should also be able to swap the
image so that it is mirrored and/or inverted if necessary to reflect what the mind expects to see,
i.e. although the camera is facing aft, the driver will be looking forward. Therefore the image on
the monitor should show what one would see in a cars rear-view mirror, i.e. the left side of the
boat on the left side of the screen, and everything right-side up. The Provix 7 flat screen LCD
monitor has front controls that include an on-off switch and volume, plus three more to invert
and/or mirror the image, or adjust brightness, color, tint, and contrast. As a small multi-system
flat-screen television with no tuner but with a pair of built-in speakers, it could also be used with
other devices such as a DVD player. A solid-state remote control and a ball-joint stand are
included.
Photo 3
There options from other sources, of course, and fellow boater Brian Shanafelt bought his
system through eBay: a new-in-the-box Standard Horizon CP1000C GPS/Plotter with a 10"
screen and a Standard Horizon VC10 color camera.
Photo 4
Although with his dextrous toes he could easily manage a remotely controlled camera and leave
his hands free for the helm controls, he chose to place a fixed mount camera near the top of his
mast for a great field of view.
Photo 5
Brian told me that My plotter has inputs for 2 cameras, and by punching a button twice you can
switch the display between camera and plotter. I set it to camera view during
docking/undocking, then to plotter once in the fairway. The plotter also has an option of
switching views automatically if desired. I usually set this option for a rear view every 60
seconds or so to see who is coming up on the stern as well having as a regular peek if towing
the dinghy. Gotta say this has been a super add-on, as on my boat, the view aft is really poor
from the pilothouse. Prior to having the camera, it was mandatory to station a lookout on the
rear of the boat in tight situations, and hope their description of the impending collision was
accurate. I am a fan of rear view cameras. Install was easy in my case - route the wire and plug
it in. At the end of the cruise, I rinse the camera off with water from a hose and have noticed no
image degradation from salt.
INSTALLATION
I had planned to mount the camera on the boat deck rail above the cockpit, but since I kept
coming back to Brians comments about the value of being able to check on what might be
coming up from behind, I adopted his masthead approach instead. That location also eliminated
the vexing problem of finding a protected route for the cable bundle to the lower helm because it
just drops through the mast with all anchor light, radar, and TV antenna cables. The masthead
was already a busy place, but it was easy to make and paint a small extension plate out of 1/4
aluminum it can be cut and shaped easily with woodworking power tools - and to sandwich it
between the anchor light and the existing top plate. The camera bracket is bolted on the trailing
edge. Since there wasnt room for the camera cable in the one small hole already through the
masts top plate, I drilled a new one.
Photo 6
Photo 7
Figuring out what ought to go where and how took longer than the actual installation. After a
couple of false starts, the job itself was not difficult, but as usual, did not go entirely as planned.
When I carelessly failed to tape the open end of the hook on my plumbers snake, it snagged on
something inside the mast and wouldnt move in either direction. It took more than an hour and
many round trips on a ladder lashed to the spreader to get it free without doing any collateral
damage. The stainless steel machine screws holding the anchor light had been threaded into
the aluminum top plate and were frozen, so the heads snapped off when I tried to remove them.
Having to grind the stubs flush required a trip home for an angle grinder, and yet more ups and
downs on the ladder. (I used Nylock nuts on the re-install.) And, at the last minute, after
removing the wiring race covers inside the pilot house, I saw a much better option for mounting
the monitor than the already cluttered chart table/dash board. Not only was just the right space
available on the face of the overhead drop-down instrument panel between the VHF and the
Garmin Fish Finder, a suitable fused 12 volt power point was nearby. Even better, its close
enough to where a driver would automatically look for the rear view mirror.
Photo 8
Still more trips up and down the ladder enabled photos of the monitor showing images from the
60° and 90° cameras in exactly the same position. They confirm Dave Winsteds
recommendation for the 90° Lens.
60° Lens Photo Photo 9
90° Lens Photo Photo 10
Checking the dinghy while at anchor:
Photo 11
After a couple of weeks use, it was clear that I didnt need to see so much of the boat, and really
wanted to see more of what was happening behind me, so I climbed up yet again and made a
small adjustment to the cameras angle. I am much happier with this view.
Photo 12
This is proving to be a very useful augmentation of the boats navigation aids (not to mention my
thigh muscles). Total cost of just under $500, 25 hours of false starts and futzing about, and 5
hours of actual work.
Experience with remotely controlled spotlights and discussions with camerasuppliers led me to conclude that the life expectancy of a remote-controlled camera mechanismin salt air is likely to be limited. More important, manoeuvring in close quarters requires both
hands at the helm, not fiddling with a camera control. What about lens angle? According to the
Winsted website, a 42° lens provides undistorted depth perception equal to the human eye,
whereas a 110° wide-angle lens is required to provide the equivalent field of view.
Unfortunately, wide-angle lenses come with perspective distortion, and, as the chart above
indicates, the wider the lens angle the greater the distortion. (Hence the warning on wide-angle
rear-view mirrors that Objects in mirrors are closer than they appear.).Dave Winfield his
partner is John Sted, hence Winsted - recommended a 90° camera as the best compromise for
my needs, and lent me a 60° camera so I could see the difference for myself.
Provix cameras also contain a microphone that broadcasts through the monitors speakers, and
there is a volume control on the monitor. The lens automatically compensates for available light
and does remarkably well in very dim conditions. In true darkness, 10 infrared LEDs assist
the bulbs surrounding the lens in the photo below and although the website indicates their
reach is marginal for a boaters needs, I was surprised at how well they performed one pitch
black night. An infra-red spotlight is available as an option.
The last all-important criterion for the camera is that it survive in the marine environment, i.e. it
must be absolutely weather proof. Claims about weather resistance or water resistance are
made by many suppliers, but all too often without any substance to back them up. Winsteds
website states that the Provix camera in its cast aluminum housing is protected against heavy
seas and that it meets IPX6 specifications (see sidebar). Winsted also states that all wiring is
waterproof, and the connectors are stainless steel. Attached to its bracket note that 2 screws
are provided for each side with one going in the center hole - the overall camera package is
quite small at 4 wide x 2 1/2 h x 2 1/2 deep.
Photo 2
To be useful for backing up, the video system must display an area severalfeet to either side of the boat and more is better. The problem is that even systems designedexplicitly for RVs have too narrow a field of view, because boats tend to be wider, often
significantly so. For my 14 beam, I want to be able to see not less than 5 to either side in order
to have time for the boat to react to helm changes, i.e. I need an angle of view providing at least
24 at the edge of the swim platform. How to get it depends on quite a few factors starting with
where the camera can be mounted. If enough height isnt available, installing a remotelycontrolled
camera or one with a wide-angle lens is an easy solution, but each has a drawback
described in the next section. This chart, copied from Winsteds website, is helpful in
determining the required equipment. (Ive substituted Width x feet from lens for Width x feet
back.)
I had intended to choose a wireless system since it promised easyinstallation. However, only the signal from the camera to the monitor is wireless, and, of course,both the camera and the monitor require wired power. Most wired kits including the Provix use a
single cord bundle that carries both the video signal and electricity, thus eliminating any
advantage to the wireless systems. But, theres a more important consideration: PC Worlds
Contributing Editor Steve Bass installed a wireless version in his car and wrote, Another
problem is the camera will occasionally act like, well, a wireless device. The gizmo picks up
interference and Ill see horizontal lines rolling across the screen; every so often the image will
just disappear. I opted for the assurance of a fully wired system.
