Autonomous solar lighting on the street, in the yard, in the country. Characteristic features of daylight

KITCHEN - NORTH, BEDROOM - EAST

Flaw natural light in an apartment negatively affects not only the metabolism and general physical health of a person. Lack of light can also lead to a decrease in mood and even depression in residents. If you feel depressed and irritable for no particular reason, think about it - is your home properly lit, does it get enough sunlight?

The Stopmakler real estate portal has prepared a small educational program for readers about correct location rooms for various purposes relative to the cardinal points, to ensure proper insolation of housing.

Of course, the number of rooms in modern apartments infrequently allows you to choose the purpose of a particular room, depending on the direction of the world. However, when looking for new housing for yourself, you definitely need to pay attention to where its windows “look”, so that later you don’t suffer from guessing why you are so uncomfortable in new apartment.

ACCEPTED INSOLATION STANDARDS

Designing new house, experts always carry out the calculation of insolation. As Grigory Altukhov, head of Federal Grid Company "Leader", explains, when calculating the coefficient of insolation of housing, many factors are taken into account:

The geographical latitude at which the house will be located (the angle of incidence of the sun's rays depends on it when it reaches the zenith);
- parameters of the apartment (width and design window openings);
- the presence of shading objects (neighboring houses) - etc.

According to the accepted sanitary norms and rules (SanPiN), insolation in residential premises must correspond to the standard duration. For example, for Moscow, which is part of the central zone, housing insolation should be at least two hours a day. Such a duration of insolation for 1-3-room apartments, according to the rules, is provided in at least one of the rooms. For multi-room apartments- at least two rooms.

Ekaterina Fonareva, commercial director of the Barkley corporation, explains that various restrictions on the location of apartments apply for each specific case, but there is one general restriction. It lies in the fact that when designing, all the windows in the apartment cannot be oriented only to the north.

WORD TO COMPASS

north side- the coldest and darkest, therefore, in those rooms where the windows face north, it is necessary to take care of the insulation of walls and windows. In addition, high-quality artificial lighting should be provided, which will compensate for low insolation.

South side- the warmest and brightest, and regardless of the season: both in summer and in winter, the southern rooms are well warmed up by the sun, receiving a sufficient amount of insolation.

East side the house is well warmed by the sun in summer period, however, it gets very cold in winter. In the morning, rooms facing east are filled with sunlight, and in the afternoon it is replaced by shadow.

West side more than others is exposed to the sun's rays and is "blown away by all the winds." When designing houses, on the western side, whenever possible, protective planting of trees is provided.

MORE SUN, MORE HEALTH

Proper insolation of housing is extremely important for human body. With a lack of natural light, metabolism suffers, visual acuity decreases, and the growth of children slows down. Also, insufficient insolation is the cause of stress: if there is little light in the apartment, the mood of the residents noticeably decreases, depression and general depression occur.

Buyers of habitation pay special attention to its illumination. Tastes differ only in the fact that someone loves the light of the evening sun, and someone - the morning, but dark apartments almost no one is attracted.

LOCATION OF THE ROOMS BY THE CORPONDING WITH INSOLATION TAKING INTO ACCOUNT

Cabinet or workshop orient "by compass" depending on what time of the day this room will be used. If you usually start work in the morning, it is better that the windows of the office, like the bedrooms, face east or southeast. In this case, the soft morning rays will invigorate you, and the insolation from the hot midday sun will be directed to the western side of the house. If the work takes place in the evening, then it is better to make an office or workshop from the western or south-western side: by the evening the sunlight becomes not as sharp as at noon, but at the same time the insolation will be sufficient for the workplace.

Kitchen, pantries and others utility rooms it is best to orient to the north, northwest or northeast. These premises are not residential, and therefore intensive insolation is not needed in them.

DETERMINING THE PARTIES OF THE LIGHT

In order to navigate to the cardinal points, it is not necessary to have a compass at hand - in most cases it will be enough just to visit future apartment on a cloudless sunny day. For example, in middle lane In Russia, the sun at seven in the morning is on the east side, by one in the afternoon it moves to the south, and at seven in the evening it illuminates the house from the west side.

The cardinal directions can also be determined by the location of the Orthodox church located next to the house. The lower crossbar on the dome always faces south with its lowered end, and north with its raised end. Altar in Orthodox church always located on the east side.

You can also navigate to the cardinal points and with the help of conventional clocks with arrows. Such clocks are placed horizontally, guiding hour hand towards the sun. In winter, the angle between the hour hand and the number 1 is bisected, and its bisector always points south. In summer, it is necessary to halve the angle between the hour hand and the number 2 - the bisector of this angle will also lie in a southerly direction.

Shooting periods during the day are divided according to the height of the Sun above the horizon with a cloudless sky (Fig. 1) into low illumination in the morning and evening at a Sun height of up to (13 ... 15) ° above the horizon. The lighting color develops from red to white, in the shadows - from blue to blue. This period corresponds to the time of spectacular shots of sunrise and sunset. The ratio of illumination of horizontal and vertical surfaces changes sharply; more normal lighting at a height of the Sun (15 ... 60) °. The color of the lighting comes to white (average daylight), in the shadows the lighting is blue or blue. The illumination of the horizontal and vertical planes gradually equalizes and becomes the same at 45°. The contrast of lighting depends on the purity of the atmosphere and is softened by diffusers on the lighting fixtures. To eliminate the blue tint of shadows during color shooting, yellow-straw filters are installed on the equalizing light devices; anti-aircraft lighting, not very suitable for shooting due to the sheer-falling overhead light of the Sun. Increasing illumination of horizontal surfaces and decreasing vertical surfaces enhances the contrast of chiaroscuro. Shooting is carried out with the lower illumination of the object or a plot important detail from lighting devices or reflector tablets: twilight (mode) lighting corresponding to the position of the Sun (0 ... 6) ° below the horizon and the sky without clouds. In this case, the brightness of the twilight sky, which creates illumination, varies depending on the purity of the atmosphere and the depth of the Sun's immersion below the horizon.

Rice. 1. Light periods of the shooting day

The necessary time for the dive is selected from the interval (15...30) min, during which the illumination should be such that the sky in the negative is worked out with density (D sky = D min + (0.1...0.9)). This practically difficult-to-determine time interval of the Sun's immersion gave the shooting the name regime (regime lighting). At this time, photography is usually carried out with the use of additional artificial lighting (backlight), the dose of which must change with the change in the brightness of the sky to obtain a constant ratio of natural and artificial illumination. In the south, the regime time is short, in the north it is relatively long (white nights). On fig. 2, a-h shows graphs of shooting lighting periods depending on the time of day and month for various geographical latitudes(cities). The graphs show the start and end times of the four main periods of natural shooting illumination for each hour of local time for various geographical latitudes from 35 to 70° every 5°. The curves are the locus of points for the solar altitudes -- 6°, 0°, +15° and -f 60°. highest height The sun for a given latitude on June 22 is indicated by a dot in the center of the graph and is provided with the corresponding number in degrees. These graphs correspond to direct sunlight in clear skies.

Rice. 2, a-h graphs shooting lighting periods depending on the time of day and month for different geographical latitudes (cities).

Illumination of horizontal and vertical surfaces of objects. Shooting objects can be different in different configurations. Their surfaces relative to light sources can be located horizontally, vertically or at an angle. A certain position of the main (drawing) light source - the Sun, as well as illumination from the sky create different illumination on objects, the difference between which determines the corresponding contrast of light and shade. The difference in illumination is a certain interval of the brightness of the object of the drug, which must be measured, matched with the characteristics of the film (processing) and reproduced in the negative (transparency).

The sun as a source of main light moves across the sky from the horizon upwards (standing height H) and in azimuth (from east to west), changing the illumination on all surfaces of the object in a complex way (Fig. 3, a, b). In most cases, scene shooting important elements the foreground of the object have vertically arranged surfaces. Facing the Sun, they perceive from it the main light, which is the key illumination for determining the shooting exposure. Depending on the height of the Sun, the key illumination changes and can be significantly lower than the illumination of horizontal, non-scene important surfaces. Lighting in cloudy weather has other characteristics.

At a low position of the Sun (Fig. 4, c), the vertical surface is illuminated by direct light almost along the normal N (angle α ≈ 0) and has maximum illumination with a low color temperature (2500...2800) K.

Rice. 3. Schemes of the movement of the Sun across the sky in terms of standing angle H (c) and azimuth (b)

Rice. Fig. 4. Schemes of illumination of the horizontal and vertical planes when the Sun is standing: low (o), medium (b) and zenith (c)

Horizontal surface perceives oblique, almost gliding light of the Sun and, according to the law of the cosine of the angle of incidence of light, has low illumination. The brightness of the vertical surface is high, the horizontal is low. At an average standing of the Sun (N - 45 °) (Fig. 4, b), the vertical and horizontal surfaces perceive the illumination from the Sun in the same way, the color temperature is close to the temperature of the average white light (5300 ° ... 5500 °) K, and the brightness of both surfaces are the same. At a high standing of the Sun (N - 50 ... 90 °) (Fig. 4, c), the vertical surface is illuminated by oblique rays of the Sun, and at the zenith by gliding rays and has low illumination with a color temperature of average white light of 5500 K. The horizontal surface perceives almost direct the sun's rays in high light and the same color temperature. The brightness of the vertical surface is low, the horizontal - high.

Fig.5. Illumination from the sky in the shadow from the Sun, where E c - illumination from the Sun, E n - from the sky

Illumination from the sky in the shadow from the Sun (Fig. 5) has a value of 6...8 times less than solar with relative uniformity. 98. Atmospheric features in daylight. The quality of daylight is determined by the degree of turbidity of the air between the Sun and the camera. Atmospheric phenomena that affect the illumination, light pattern and color of an object include atmospheric, celestial and optical haze, haze, fog, drizzle and rain. If these phenomena occupy a small part of the area (10 ... 30%) within the photo frame, then they are elements of the shooting object with their own brightness and color and do not affect the lighting. If they serve as the environment in which the subject is located, then they largely affect the illumination and color of the lighting. Any atmospheric phenomenon and the conditions in which it develops affect the light-optical pattern and the photographic quality of the image, and the visual effects that occur, for example, in rain, snow or fog, specify the situation of the action. Atmospheric (molecular) haze is a uniform light veil (environment), covering the distances of the earth's surface. Caused by the scattering of sunlight by a layer of air. In clean air with relatively zero humidity, the rays of the blue-violet part of the spectrum scatter more strongly than the green, yellow and red ones, so the atmospheric haze, and with it dark distant objects, acquire a bluish color (“blue distances”). Atmospheric haze smooths out the differences in brightness and color of distant objects and thereby worsens their visibility up to complete disappearance. The nature of the haze is determined by the color of the halo around the Sun and the state of the atmosphere. The presence of molecular haze makes the halo very weak, the sky around the Sun becomes bluish. With a relatively increased air humidity, the haze thickens, and the halo acquires a bluish-steel tint. In black and white photography, atmospheric haze is reduced by using yellow, orange, and red filters (especially in aerial photography). The use of these filters is not effective if the haze is caused by the scattering of light by particles of dust and fog, since in this case the scattering of sunlight in all parts of the spectrum is the same. In color photography, filters to eliminate molecular haze are not used. A small blue atmospheric haze near the horizon during color shooting is even undesirable, since the aerial perspective expressed by it destroys the dryness and rigidity of colors, chiaroscuro becomes softer, and the image takes on a certain color. Sky haze is a type of atmospheric haze that differs high content atmospheric moisture. The quality of solar illumination, which affects the illumination of the object and the color of the sun's rays, depends on the density of the celestial haze. The light of the Sun, passing through the sky haze in the blue-green part of the spectrum, is significantly weakened and becomes warmer. The white parts of the subject take on a slightly reddish tint, but the shadows do not have a pronounced blue tint as they are illuminated by whiter light. Sky haze has a positive effect on the quality of color in the image: the results are better than with pure blue skies and light molecular haze, aerial perspective is expressed more clearly. Significant impact on solar lighting renders a thick heavenly haze (professional expression "The sun in milk"). Lighting with it is similar to daylight, when the rays of the Sun pass through high cirrus clouds. At the same time, despite the fact that the illumination drops almost twice, the shadows are well illuminated by the diffused light of the Sun, the contrast of chiaroscuro decreases and the general illumination becomes the most favorable for creating a three-dimensional pattern. The colors of the object under such lighting are transmitted in the most full color, there are no color distortions from a clear blue sky. Optical haze is created by local air turbidity due to the temperature difference between the layers, which causes the appearance of air oscillating jets of air. Optical haze is especially noticeable in hot, dry weather over asphalt in the city, dry soil in the steppe, and heated roofs of buildings. Light in the presence of optical haze is sufficiently polarized, therefore, in this case, the use of polarizing filters is effective. Haze is cloudy air caused by solid particles of smoke, burning and dust suspended in it. The high intensity of haze reduces the visibility of objects sometimes up to 1 km. Over large cities in calm weather, there is haze associated with clogging the air with dust and smoke of local origin (smog). It makes the atmosphere near the earth's surface dark grey. The brownish or grayish-brown color of the haze significantly changes the color of the illuminated daylight: it makes it reddish, sometimes the Sun is perceived as red through the haze. Dust haze as a kind of haze in black and white shooting is not filtered by yellow, green and even orange filters. In any shooting, the sky is perceived as gray-white, and near the horizon as dark gray. The light scattered by the dusty haze is partially polarized, therefore, when shooting in the steppe regions, a polarizing filter is used to reduce the excessive brightness of the sky. Fog (a cloud lying on the ground) is an accumulation of small water droplets in the surface layer of the atmosphere with a height of up to hundreds of meters, reducing visibility from (1 ... 3) m to 1 km. Fog is formed as a result of sublimation or condensation of water vapor on aerosol (liquid or solid) air particles and is divided into evaporation fog and cooling fog. Evaporation fog occurs when additional water vapor enters cold air from a warmer evaporating surface, cooling fog occurs when the air is cooled below the dew point temperature. At the same time, the water vapor contained in the air reaches saturation and partially condenses. Cooling fogs are the most common. White light is strongly scattered by fog due to the significant excess of the diameter of moisture particles of the wavelengths of the spectrum rays. Only infrared rays with a wavelength greater than the diameter of the fog droplets pass well through the fog. When light reflected from objects passes through the fog, some of the rays reach the lens of the camera, while the other is scattered, and many weakened rays coming from the entire mass of fog reach the lens. The rays that have reached the lens draw an image of the object, and the scattered ones impose a uniform gray veil on it, reducing the contrast of the image. With a high density of fog, its veiling effect is significant, the pattern of the image is not observed, the photographic material in the camera is evenly illuminated by diffused light. Fog has its own brightness, in most cases more than the brightness of the object, since the "light source" in this case is itself. In fog, horizontal and vertical surfaces have the same illumination. First of all, blue rays are scattered in the fog, and lastly, red rays of the spectrum, therefore, a colored object, depending on the density of the fog, first loses blue, then green, and last saturated red tones. For this reason, a person's face, shot in fog, does not lose its pinkish hues. Bright red colors, fire and sources of red in the fog are clearly visible. As the distance from the camera to the object increases, the color of the object in the fog is quickly lost. At certain distances, the image of the object takes on pastel tones, as the fog greatly whitens the color, superimposing an additional white veil on each color tone, softening the contours and reliefs. When shooting against the Sun (kotrazhur), when its translucence is felt, the fog turns red, and the background appears as if through a reddish veil. When photographed from the Sun (to the north), the fog appears colorless, gray or bluish depending on its density. Drizzle - atmospheric precipitation in the form of very small drops with a diameter of up to 0.5 mm (larger than fog drops and smaller than rain drops). Drizzle falls from stratus and stratocumulus clouds and, depending on the density, has the properties of fog or rain. Rain - precipitation falling from clouds in the form of water droplets with a diameter of 0.5 to 6 ... 7 mm. The optical effect of rain lies in the fact that an additional optical medium appears between the camera and the subject in the form of a dense water sheet that absorbs and scatters light. When it rains, the drops themselves become a luminous medium that exposes the film (like fog, for example), so distant black or colored objects cannot be depicted as either pure black or saturated color. The color is whitened by the veiling action of rain as well as by mist. In dense continuous rain, first of all, blue colors cease to be distinguished, then green, and then red colors. In addition to this, in the rain there is a shine on all surfaces without exception, since the veil of rainwater makes them glossy, and the reliefs of glossy surfaces stand out well. Reflex light appears on the folds, bends and uneven surfaces, allowing you to clearly see the shape and volume of objects. Puddles of water on the ground, asphalt, pavement reflect the light of the sky, creating additional illumination from a lower point, in the presence of which it is sometimes possible to exclude the lower illumination of the plot important details object. Glare and reflections allow you to shoot against the lightest part of the sky (a kind of backlight) and get an image with relatively minimal illumination. When shooting in black and white in the rain, you can get multifaceted images (especially in a landscape), and when shooting in color, for example, a picture in which the color in the foreground of the image is relatively saturated, and in the depth of perspective is reproduced in the achromatic range of blacks and gray tones(red traffic light in the foreground with a gray tone in the background). Reflections and glare at the same time convey a sense of volumetric form and airy (tonal) perspective. Cloudiness, depending on the nature of the clouds and the degree of their distribution over the sky, creates different illumination in the color of daylight. There is a sharp difference in the intensity, contrast and spectral composition of illumination under the Sun with a cloudless sky and under continuous clouds with closed sun, The area of ​​clouds in relation to the sky-vault affects the proportion of diffuse, reflected and direct light from the Sun in total daylight. The greatest illumination is observed when the sky is almost completely covered with thin light clouds with an open or slightly veiled Sun, the smallest - when the sky is covered with clouds (cloudy weather). The greatest contrast of daylight is observed when the Sun is open and the sky is clear, since the illumination from the sky is 6...8 times less than the illumination from the Sun (significant contrast). Less contrast - with a sky partially covered with white clouds that reflect sunlight well, and minimal or no contrast - with a sky completely covered with clouds. Data on illumination and color of daylight are given in the reference book.

Home ownership outside the city is not just a luxurious house, but also a land plot that requires careful design in the process of arranging in the landscape style you like. At the same time, one should not forget about the illumination of the territory, without which it is impossible to walk around the garden at night.

In addition, it is also considered an ornament, thanks to which plants that become invisible at dusk acquire a fabulous and exclusive appeal when properly illuminated. However, which lighting method should be preferred? It is not always possible to supply electricity.

The way out of this situation lies in the arrangement of solar-powered lamps. They appeared in our country relatively recently, but quickly won a huge demand among the owners of country cottages.

The Secrets of Solar Lighting

What is the difference between conventional lighting? The design of devices includes certain details and can have a variety of parameters, external characteristics, while possessing similar principle functioning. It consists in the fact that the incoming energy from the photocell is transferred to the battery, and then to the LED.

The upper part of the device is covered by a ceiling, equipped on special legs, or suspended on a mount. Look at the photo of the arrangement of solar lighting devices on the resource.

The area of ​​use of these devices is diverse, not limited exclusively to private households. They originally fit into the landscape decoration of park areas, are used as lighting for the facade of buildings, successfully decorate fountains and sculptures.

Varieties

To the most modern models solar devices include lawn, park, and wall. The most common are wall-mounted options that illuminate garden areas and squares.

Such an element can be located in a place illuminated by the rays of the sun. The batteries in these instruments support lamp operation for ten hours.

Devices for public gardens are equipped with large aluminum panels. Their difference lies in design features capable of protecting the contents of the luminaire from moisture. Undeniable dignity there is a long operating period. Such garden lighting works smoothly even in bad weather.

Lawn appliances in most cases have small dimensions. They use LEDs as a luminous part. As for the form itself, the advantage of solar lighting devices lies in the diversity and style of each individual model. Lanterns are used to illuminate paths, plants, and the attic.

Advantages and disadvantages

The advantages of such devices include a diverse area of ​​​​use. They are well suited as interior decor for suburban residential buildings and office buildings. By equipping garden lighting on batteries that operate from sunlight, even in the shady part of the garden, it is possible to focus the necessary attention on an object placed in that area without any problems.

In addition, such lanterns will help shrubs and trees develop well, as they will be illuminated at night. Operates lighting from solar batteries and in the squares, on the streets.

At the same time, when planning such a purchase for a suburban area, it is important to understand that many models are not repaired. Also the most regular options Doesn't charge quickly, especially on cloudy days. In addition, not every battery tolerates cold very well. This moment important to consider when buying a particular model.

However, despite the presence of disadvantages in the characteristics of solar lamps, they are not without numerous advantages:

• mobility;
• security;
• variety of capacities;
• saving electricity;
• variety of sizes, shapes, shades.

What nuances to pay attention to Special attention at the time of buying

Since in these lamps the light source is LEDs, their required number directly depends on the sharpness of the lighting. Also an important nuance that requires utmost attention in the acquisition process is the type and characteristics of the battery. The duration of operation of the LEDs at dusk depends on the voltage, as well as the capacity of the device.

The level of protection of the device is indicated by special numbers, as well as letters. At the same time, the higher the marking number, the greater the protection of the device from negative environmental influences. However, there are lighting devices with a motion sensor that are equipped even on water. Their difference lies in the ease of installation in the required place.

In this case, it is desirable to use these devices as additional lighting. It looks quite effective in combination with spotlights.

Most requested options

Today, garden lighting devices are presented on the market as products of foreign and domestic manufacturers. Which company to choose depends solely on your preferences. If you need to learn how to make a solar device with your own hands, watch a video from professionals.

Among the goods from domestic manufacturers, pay special attention to Cosmos devices, which are equipped exclusively in areas with unhindered access to the sun's rays. It is in this embodiment that battery charging will be observed, and at night the energy will turn into amazing lighting.

Uniel lamps belong to foreign high-quality goods. Their main purpose is to provide high-quality illumination of the territory and decoration structures. Lanterns of this type are created in an exclusive design and can be used both as lighting devices and as an unusual decoration.

Photo of solar lamps

The main source of natural light is the sun. The spectral composition of solar radiation at the boundary of the atmosphere is usually approximated by the radiation of a black body with a temperature of K. The true distribution of energy in the spectrum of solar radiation is somewhat different from the distribution for a black body with K: in the region of 0.4 ... 0.75 μm, the Sun radiates more energy, than the black emitter at K, in the ultraviolet region it is less, and in the infrared region the differences are insignificant. The sun as a radiator is a sphere and theoretically radiates a diverging stream of rays, however, due to the large distance of the Sun, its radiation on the earth's surface practically represents a stream of parallel rays. The energy illumination that the sun's rays create on a plane perpendicular to them outside the earth's atmosphere at an average distance from the Earth to the Sun is characterized by the solar constant.

The illumination of natural landscapes is determined by the height of the Sun above the horizon and the influence of the atmosphere. The height of the Sun for an area with geodetic latitude and longitude is determined by the following calculation formula:

where is the declination of the Sun on the date of observation; is the difference between the longitudes of the Sun and the observer (hour angle).

The longitude difference (degree) is related to local time by the relation , where is the time in hours and its fractions.

At a given moment of Moscow time, the value is determined by the following equalities for winter and summer time, respectively:

where is the equation of time (time correction) in fractions of an hour.

The declination of the Sun is given in a table, but with sufficient accuracy for modeling it can be determined analytically: , where is the time in days from the diurnal equinox (March 22) to the date of shooting. Values ​​are determined by nomogram or by tables.

To simulate realistic images in natural light, it is also necessary to determine the azimuth of the Sun, which is calculated using , and :

In image synthesis procedures, it is advisable to use a unit vector , indicating the direction to the Sun. If we use the right topocentric coordinate system, in which the axis is directed to the north, and the axis is perpendicular to the Earth's surface and directed to the zenith, then the components of the vector along the axes will be determined by the following relations:

(1.3.4)

Note that for the characteristics of the position of the Sun, along with the height, the zenith distance is used.

The influence of the atmosphere is manifested in the weakening of direct solar radiation and its scattering. In accordance with this, the illumination of the earth's surface is determined by two light fluxes: attenuated direct radiation and diffuse radiation of solar radiation going to the Earth.

Significant instability of the properties of the atmosphere, a significant number of factors that determine its variability, do not allow an accurate forecast of illumination. Approximate models with a limited number of parameters characterizing the optical properties of the atmosphere are usually used. The average standard atmosphere model is widely used for calculations. The spectral illumination created by the Sun at the Earth's surface on an area perpendicular to the sun's rays, with a cloudless sky and a standard atmosphere, is determined by the formula

, (1.3.5)

where is the spectral illumination created by solar radiation at the boundary of the atmosphere; is the optical depth of the atmosphere.

The generalized parameter can practically be used in the range , within which the attenuation of direct solar radiation is due mainly to molecular and aerosol scattering (Fig. 1.3.1).

Rice. 1.3.1. Attenuation of direct solar radiation in the atmosphere:

1 - solar radiation at the boundary of the atmosphere; 2 - solar radiation near the earth's surface; 3 - aerosol dispersion; 4 - absorption in the atmosphere

For this range, the wavelength dependence for a standard atmosphere is described by the empirical formula

where is the optical depth of the atmosphere at nm. When calculating according to (1.3.6), the values ​​are substituted in nanometers.

In calculations, several typical values ​​​​are usually used. For a moderately turbid atmosphere, it is 0.3. Weak turbidity of the atmosphere corresponds to increased turbidity, high.

The illumination created by the direct radiation of the Sun on an arbitrarily oriented site is determined by the angle between the unit direction vector to the sun and the unit normal vector to the site:

, (1.3.7)

where is the scalar product of vectors and .

The image synthesis program must take into account the condition of non-negative illumination

If the conditions (1.3.8) are not met, this side of the site is not illuminated: . The unit normal vector to the area must be directed from the surface whose illumination is being calculated. This means that the area is fundamentally characterized by two unit normal vectors and , which define its two sides. It's obvious that .

Note that from general formula to determine the illumination (1.2.23), the formula given in the literature for the illumination of the earth's surface directly follows. For a horizontal ground and hence .

The illumination created by scattered radiation is determined by the brightness of the sky. The importance of taking into account scattered radiation is due to the fact that it determines the illumination of scene areas that are in the shade.

The brightness of an arbitrary point in the sky is a function of four main parameters: the height of the Sun, the transmission of the atmosphere, the zenith distance of a point in the sky and the angle between the direction to the Sun and to a given point in the sky.

The calculation of the illumination of an arbitrarily oriented area, taking into account the true distribution of the brightness of the sky, requires numerical integration using tabularly specified functions. This seriously complicates the procedure for calculating the illumination of points in the picture plane. The calculation procedure can be significantly simplified if the brightness of all points of the sky is assumed to be the same and equal to some average value. The average brightness of the sky can be approximated by the dependence of the form

The quantity depends relatively weakly on and . In some cases, it is assumed to be constant. A more accurate approximation can be obtained by assuming . At the same time, the differences in the results obtained on the basis of more accurate models and those presented above are small. The maximum differences reach 20% only at a significant height of the Sun ().

To determine the illumination from the sky of an arbitrarily oriented area, consider the general scheme for determining the illumination created by an extended source (Fig. 1.3.2).

Rice. 1.3.2. Determining the illumination of an arbitrarily oriented area by the sky

In accordance with (1.2.16), the illumination from the firmament of the site is determined as follows: , where is the projection onto the illuminated plane , in which the site lies, of the visible part of the celestial sphere. before . Outside this range, the values ​​are practically zero.

Although the transition from energy system to lighting does not cause fundamental difficulties, however, for systems in the visible range it is more convenient to use calculation formulas that express illumination directly in the lighting system. For such calculations, a relation can be used based on the known in , but supplemented by taking into account the slope of the illuminated area:

where - illumination of the plane perpendicular to the rays of the Sun at the boundary of the atmosphere in the lighting system of units; are coefficients characterizing transparency and dispersion in the atmosphere.

For the average parameters of the standard atmosphere ; . In accordance with (1.2.29), the maximum illumination of a horizontal platform on the earth's surface for standard conditions is 106,000 lux (at ).

The amount of natural illumination is greatly influenced by the nature of the cloudiness. The presence of clouds causes a significant increase in scattered radiation. With broken clouds, the illumination "on the Sun" is 10 ... 30% higher than in cloudless weather, and the illumination in the shade can increase up to a twofold value. This circumstance is the reason for a significant scatter in the experimental data on illumination in the shade and justifies the use in computer graphics of relatively simple models for calculating illumination, the use of correction factors that increase the value of illumination in the shade compared to those calculated at solar angles .

In the past, any space was totally dependent on natural light. There was a time when it went out of fashion and people hid the interior of their home behind layered curtains. Today, humanity is once again returning to the most active use of natural lighting, because it brings comfort and well-being.

Besides - and this is important! - efficient use natural light reduces electricity consumption by 50-80%. We will talk about how to "catch" the sunlight and make it your ally.

Natural light in the rooms

Human circadian rhythms, on which our health directly depends, are regulated by various qualities of light: its color, direction, quantity. The sun and the rotation of the earth are the main conductors of this orchestra.

The famous Roman architect of the 1st century, Vitruvius, proved that light can even heal, and insisted on the importance of a certain orientation of the building to the cardinal points.

The following requirements are imposed on modern buildings:

• from the beginning of spring to the beginning of autumn living rooms the house should receive direct sunlight for at least 2.5 hours a day;
• 60% of the rooms in the house should be well lit;
• the window area should be about 1/5 of the area of ​​\u200b\u200bthe room;
• the top of the window cannot be placed below 1.9 m from the floor (the higher the ceiling, the higher the window should be);
• the distance from the window to the opposite wall should not exceed 6 m, and the distance between the windows - one and a half meters.

When deciding in which part of the room to locate a particular room, be sure to consider the intensity of lighting. So, for nurseries, living rooms, study rooms and other rooms where we spend most of our waking hours, it is preferable to choose more lit rooms, with windows oriented to the south or east.

When zoning rooms, attention is paid to functionality: work surfaces, writing and dining tables located in the brightest areas of the room, but the places of rest can be less lit.

Natural Lighting Strategies

Natural lighting is of the following types:

• lateral - penetrates through the wall along the perimeter of the building, i.e. through ordinary windows;
• top - penetrates through windows in the upper part of the walls or roof;
• double-height - it is organized due to windows located one above the other in large and deep rooms.

You can choose one or another lighting strategy only at the stage of designing a home. However, even with a finished house or apartment, you can work to capture as much sunlight as possible.

• With a lack of light, ready-made window openings can be increased, and even additional ones can be cut through.
• Illumination is improved by special reflective surfaces that direct light from the window to the ceiling, from where it is scattered around the room.
• The ceiling, walls and floor must have sufficient reflective properties: for the ceiling, the reflectance is 80%, for walls - 50-70%, for the floor - 20-40%.
• To make the room seem lighter, they try to use light colors in it: this applies to the coloring of walls, floors and ceilings, and interior items.
• Due to the reflection of the sun's rays, the illumination is added by mirrors and smooth varnished surfaces.
• Make sure the windows are not obstructed dense bushes and tree branches.
• If you want to get rid of direct sunlight, for example, in working area at the window, you can curtain its lower part. General lighting in the kitchen will remain.

You should not get too carried away in “catching” natural light, because the room can turn out to be overexposed, and the glossy floor will hit reflected eyes. noon sun. It is important to maintain uniformity.

Natural light, color and fixtures

North: there is always a somewhat subdued cold light, which can be successfully adjusted due to the appropriate shades of yellow, red, orange, brown, and, oddly enough, white. blue and green color in such a room they will make a person feel cold.

South: cool, warm and sunny! Feel free to experiment with colors, and in case of too bright natural light (southeast window), adjust it with curtains of the appropriate density.

East: the bright beginning of the day is replaced by a gloomy evening. In such an interior, a combination of warm and cold shades is appropriate, helping to even out uneven lighting. A joyful mood will be created by contrasting combinations of turquoise and terracotta, lilac and gold.

West: The second half of the day in such a room is saturated with light. Use calm, neutral tones, contrasting colors. The northwest will require warm pastel shades of golden yellow, the southwest - silver gray, greenish blue.

artificial lighting should follow the natural and organically complement it. Control systems with light and presence sensors are very convenient, allowing you to turn on the lamp only when there is a real need for it.

We should not forget about the color rendering of the lamps, so that in the evening your interior matches its purpose and does not lose its carefully created attractiveness.