A weather web-camera should be located with a clear and uninterrupted view of the sky. However, how that view changes throughout the day and, over the whole year, is an important consideration. Some questions to ask: Is one part of the sky more active than others? Do more interesting clouds build a particular direction? Are spectacular sunsets or sunrises more likely to occur in one season rather than another? Does one direction have an appealing landscape to set the clouds against? A weather web-camera location is often a compromise, so a number of candidate locations should be given due consideration. A weather web-camera is not strictly restricted to just one view all year round; so the web-camera could be redirected or even relocated over the course of a year to capture the most favourable weather action.


Creating a plan of the local site will show where and when the most interesting weather
action is likely to happen. This will also outline where there are obstructions to the scene.

It is essential to consider where the Sun is going to be in the web-camera's frame. This is not just for artistic composition, but there are implications on exposing a web-camera to excessive levels of light and heat. Sunlight beaming into a web-camera's lens can degrade the performance of the imaging chip. A weather web-camera is likely to be fixed onto one view 24-7, which means the Sun could remain in frame for two to three hours at a time. Furthermore, as the seasons change, so will the position and intensity of the Sun.

Most brands of brands of web-camera are tolerant of the Sun being in frame due to the wide angle nature of their lenses. Fitting a telephoto lens will exponentially increase the chance of damaging a web-camera if the Sun passes across the frame! Sun damage is more likely at lower latitudes where sunlight is stronger but, the Sun is more likely to climb out of frame sooner. At higher latitudes, the Sun is more likely a hazard in the late spring and early autumn when it still has strength, but is low enough to shine directly into the lens.


In the winter months, the setting Sun unobtrusively transits the side of the frame. However, as the year progresses, the Sun intrudes ever higher into the frame, becoming stronger as it rises. Between the spring and autumn equinoxes though, the Sun passes safely over the top of the frame.

Ambient temperature and humidity have implications for a web-camera. The ambient temperature range inside a typical home is from ten to thirty degrees centigrade (50-86°F). On a window sill, this range expands from zero to forty degrees Celsius (32-104°F). Add on a web-camera's own heat output of some twenty degrees Celsius (68°F), and on a summer's day, a web-camera located on a window sill could easily go outside of its operating temperature of around fifty degrees Celsius (122°F). As a general rule, locations exposed to the Sun from midday through to mid-afternoon should be avoided.

Overheating is likely to cause a non-fatal malfunction, but in extreme cases, the web-camera may lose its firmware and become a pricey paperweight. Where extreme heating conditions are likely, a small blower fan can be fitted to cool the camera. But in practice this will only lower the temperature to some five degrees Celsius (9°F) above the ambient temperature.

A location that seems right during the daytime may overnight, become cold and damp. The frequent build up of condensation will corrode connectors and fixings, and bring about the inevitable a build up of mould. Leaving a camera switched on overnight throughout the cold winter period may help to avoid the affects of condensation and possible frosting.

High humidity environments such as those found in the tropics will cause web-cameras to deteriorate due to corrosion and bio-chemical reactions. Where a location contains corrosive aerosols, such as the salt in a maritime environment, even a web-camera mounted inside will experience corrosion of connectors and even circuit boards. In these circumstances, an external camera enclosure may be required inside.

A good location gives the best view, but places the web-camera under the least stress.

Where a web-camera is likely to be exposed to environmental stress, some form of protective enclosure should be considered. Even if the web-camera is located inside a building.

The interesting part of the sky can often occupy a significant proportion of the horizon. Which means for a weather web-camera trying to capture weather phenomena, a wide angle lens is most desirable.

Most IP cameras are designed for the surveillance of work stations, stairwells, etc, and are supplied with lenses that are slightly wide angle. This equates to roughly one eighth of the turn of a compass; for example, with a camera pointing west, the edges of the frame will be inside the south western and north western horizons. Desktop USB webcams have wider angle lenses because the subject (a person sat at their PC) is only inches from the camera. These wide angle lenses cover a lot of sky, for example from the south west to north west horizons, but the wide angle lens may cause pin-cushion distortion which can make clouds look small and the sky unnaturally curvy.

Extra ultra-wide-angle lenses can be purchased for web-cameras separately, but these are vendor specific and often require disassembly of the web-camera to fit them. Furthermore, the wider the camera lens, the smaller clouds become; an attractive cumulus may turn into an indistinct white blob. A fish-eye lens gives a dramatic 360 degree view, but the detail contained within, especially around the horizon, will be of little use to anyone.

It is possible to fit any kind of lens to a web-camera. However, the tiny size of an imaging chip will often fail to cover the image field of the ad-hoc lens, turning the web-camera into what seems like a telescope! This is especially true when fitting 35mm format lenses to web-cameras. Furthermore, imaging chips are sensitive to infra-red wavelengths. Which is why all web-camera lenses are fitted with an infra-red blocking filter. Fitting an ordinary filter-less lens to a web-camera will result in some very bizzare pastel green and blue hues.


Simulated, the greater the field of view of a lens, the worse the distortion of the scene. The 70 degree scene is typical of a USB webcam, whereas the 45 degree scene is typical of an IP camera. A slightly-wide angle lens with a field-of-view some 45 degrees gives the most sky information with the least sky distortion.

A well positioned web-camera respects the rules of composition. Exclude from the scene where possible, close-in distractions like street lights, cables, poles and aerials, as these may dominate the scene. In most urban environments some of these distractions are unavoidable. Buildings, rooftops and distant hills add a sense of perspective and depth to an image. Trees in frame will provide a sense of season, even when bare or covered in snow. Horizons should be horizontal; a wonky web camera makes it seem the web master neglected to straighten the camera after it was knocked awry! A web-camera scene that is pleasing to the eye will always bring repeat visits to a web-camera homepage.

Rooftops and hills create a sense of depth	Avoid close-in distractions
Wonky horizons are just annoying	Deciduous trees can give a sense of season

The sky always looks bigger when the scene is set in context with the horizon. Without, perspective is lost. Typically, the horizon should be one fifth to one third of the frame.

Below, pitched too high, no perspective makes these clouds ambigiously sized.



Below the buildings and horizon scale the sky correctly.



Below is not a weather camera!

A good photographer knows how a sky can be made a deeper shade of blue, and clouds made to stand out, with the use of a polarising filter.

The best orientation for a polarising filter is the one that gives the maximum colour depth when the sun is directly to the left or the right of the scene. So at midday with the sun due south, the sky to the east or the west will polarise best. Clear blue skies with Cirrus will yield the best results. Skies covered in mist, haze or low cloud, will show little or no effect at all.

A polarising filter also provides a degree of neutral density, which reduces the amount of strong sunlight entering the web-camera; which is a good thing. Filter types such as ultraviolet and skylight are generally unnecessary for weather web-camera operation. Coloured filters can be experimented with for special effects!


The effect of polarising the sky can range from subtle to very dramatic!

Polarising filters are relatively expensive and, given the tiny size of filter required for most web-camera lenses, is a large photographic multi-coated filter necessary? There are other sources of polarising filters such as polarising sunglasses or, illustrated here, a linear polarising filter strip covering the LCD display inside a defunct pocket calculator. These strips can be cut into centimeter square filters and fixed in place using tape. Exposed to direct sunlight, they are likely to fog or bleach; from experience, this occurs over one to two years.

Most web-cameras can broadcast or stream live video images to any place on the internet. Indeed, live streaming is a must-have for CCTV monitoring. However, for a weather web-camera, where the subject changes over minutes rather than sub-seconds, streaming is unnecessary.

From the viewer's point-of-view, watching a live video stream of clouds is rather like watching the minute hand of a clock. Things move, slowly. Of course, major weather events like lightning storms, hurricanes and tornados benefit from live video feeds. Although by streaming extreme weather events, there is a requirement to fit the system inside a very hard case!

Uploading a single image every few minutes is both bandwidth efficient and, means web browsers will not require the installation of a third-party plug-in - which is not the case when viewing video. And due to issues surrounding installation and plug-in security, people are reluctant to install them. A case of no plug-in, no problem.

A weather web-camera should upload a static image every five to twenty minutes. Given the rate at which the sky changes, this is good enough to provide a live view of the sky.	For a Timelapse effect, the upload period is reduced to one image every five to twenty seconds. Software may be required to play back the images in quick succession.

Some points to consider when locating a weather web-camera service:

• There is a Duty Of Care when locating a web-camera, so avoid causing hazards to public safety both in public and private places.
• Never point a web camera directly at someone's residence. Not only is this discourteous, but the residents may have a prima-facie claim that you violated their privacy by broadcasting their daily activities to the web. Be courteous to neighbours and frame the image in such a way that any window of any property occupies just a few fuzzy pixels around the edge of the frame. After all, the sky is the action, not the bedroom window across the block.
• There should be no issue with including buildings that are in clear public view from a public right of way such as houses, office buildings and factories, provided they are not made the subject of the frame and, the resolution of your image is such that no useful information can be gleaned from road names, house numbers and car registration plates.
• However, even though they may be in full public view, avoid broadcasting views of banks, government buildings, school playing areas and military installations. Even if they are featured on Google Street View. A weather web-camera shows rooftops.
• Be aware of Data Protection legislation. This is designed to protect personal information such as names and addresses on company databases. It is highly unlikely a Court would rule that pictures of clouds are personal data, especially when most weather web-cameras are non-commercial personal (hobby) projects.
• Be prepared to reposition a camera if a resident has reasonable grounds to raise an objection. Some people complain (in green ink) because they can.
• There is precedence for web masters being asked to shut down webcams because they do not have the rights to transmit an event; such as a street music festival happening outside their window. In these circumstances, it may be a reasonable request if the web-camera is streaming live video and audio and, the event is not in clear public view. But this would be a most unreasonable request for a weather web-camera. No-one owns the weather!
• Web cameras in public places can be abused by the public. Displays of disorder and indecency are not unheard of. Unlikely to be an issue if a camera is pointing at the sky.
• Disclaim. State, this web camera is for monitoring the weather and is not intended for the surveillance of persons or places, and ensure the camera is pointing at the sky.

• Know where the active sky is most likely to be
• Know how the position is affected by heat and light
• Consider more than one position throughout the year
• Avoid the midday Sun to avoid overheating
• Avoid condensation and frosting
• Avoid dust
• Avoid pesky varmints
• Consider more than one location
• Seek a pleasing view
• Include objects that give a sense of perspective
• No more that one third of the frame should be landscape
• Keep horizons horizontal
• Avoid close-in distractions
• Include trees
• Polarise the sky
• Do not invade privacy
• Be aware of content piracy
• Streaming video is only needed for extreme weather conditions!