إضاءة الاستوديو وملحقاتها ..
الملحق ..
كتاب التصوير الفوتوغرافي
Studio lighting and accessories
Apart from studio flash units ( see p . 150 ) . all artificial studio lighting has either tungsten filament or tungsten - halogen bulbs . Tungsten lamps provide a con stant light independent of the camera , allowing you to select any shutter speed and enabling you to see at a glance the exact effect of your chosen lighting .
Choosing equipment
The kind of studio equipment you should choose will depend on your studio space . For a reasonable sized studio ( not less than 20 ft / 6 m ) , you will probably need two tungsten - halogen lamps - one with a diffused light , and the other with a more concentrated beam . You should have one or two reflector screens which will store easily when not in use . If you cannot afford a background stand , you can use one wall of your studio room instead - as long as it is painted white or a very pale color . A spotlight and a set of multi colored gelatin sheets will turn this sur face into any color you desire . This equipment will provide you with a very efficient basic studio . You can supple ment this by renting extra equipment for special shots . Large professional photo graphic dealers often have a rental de partment where you can borrow almost any kind of lighting equipment , cameras and lenses . It is generally far more economical to rent items of a specialized nature if you only use them on rare occasions .
Bulbs
Tungsten filament bulbs are far brighter than normal domestic types , but they are less durable . The cheapest type , No. 1 photofloods , last only about two hours . Use these with caution because at the beginning and end of their working life their color temperature can be higher than 3,200K ( to which Type B film is balanced ) , making your pictures too warm . No. 2 photofloods last longer - about 100 hours and are constant in color temperature throughout their life . Tungsten - halogen lamps are more expen sive , but they are more powerful and last longer . The introduction of tungsten halogen lamps produced several new types of studio and portable artificial lighting - because tungsten - halogen bulbs are considerably smaller in size than filament bulbs this has enabled the manufacturers to make the whole light source smaller .
Types of lamp
Spotlights use a fresnel lens to produce a strong , concentrated beam of light . You can narrow this beam still more by moving the bulb further away from the concave mirror at the back of the spot . Most modern spots use tungsten - halogen bulbs . You can also buy miniature spots which you use for lighting only small areas of the subject .
Floodlights have wide built - in reflec tors , producing more diffused light . Some have additional mushroom reflec tors in front of the bulb to increase diffusion still further .
Tungsten - halogen bulbs have led to the introduction of several portable floodlights . We use a portable Lowel light for a lot of our work . It is extremely bright but it has a large reflector , so it gives a very diffuse light which covers a large area . The whole lamp folds up into a fairly small suitcase for location work .
Lighting heads
The spotlight , below left , provides a concentrated , narrow , partly - adjustable beam of light suitable for low key studio studies . The floodlight , bottom , has a large reflector , giving a wider beam and softer quality light . The Lowel light , below , has two tungsten - halogen bulbs behind a metal bar which point toward a wide . silvered reflector , making all its bright light indirect and softer in quality .
Portable tungsten lamp This tungsten - halogen lamp operates from a small battery power pack . It provides a very powerful source of light , but unless you fit a diffuser it can be harsh in quality .
Accessories
There are several accessories which modify and control the size or quality of a studio lamp's beam . You can soften light with diffusing screens or umbrellas , and you can use barn doors and snoots to restrict it to a narrow area . With older style lamps you can cut out shapes from black cartridge paper and attach them to the lamp with adhesive tape to restrict or alter the beam ( although this is not possible with modern tungsten - halogen lamps because of the extreme heat that they emit ) .
Reflector screens are very important equipment in a portrait studio and can be placed at any distance from the sitter to provide very effective fill - in . You can make screens by covering large 3 × 7 ft ( 1x2 m ) hinged wooden frames with white cardboard .
Inverse square law
This states that when a light source takes the form of a point , the illumin ation of a surface is inversely propor tional to the square of the distance of that source . When you double this distance the illumination is quartered . To maintain constant exposure while allowing for this effect , increase the aperture by one stop for every doubling of the distance .
Diffusers D You place diffuser screens . far right , between the light and the subject for a softer effect . Umbrellas , right , are made of a soft silvered material . They spread and diffuse individual studio . lights or flash units , giving a shadowless effect .
Lighting accessories A A snoot ( 1 ) narrows the beam of light to light only the hands , for example . You can adjust barn doors ( 2 ) to any position to control the beam of light . Scrims ( 3 ) and half - scrims ( 4 ) reduce the amount of light .
Background paper V " Colorama " papers are the most popular method of achieving an even - colored . plain background . You hang the roll or rolls of paper on a telescopic stand , and pull out the amount you need .
Reflectors An efficient , well - placed reflector screen can do the work of an additional light source . You can use home made or purpose - built screens , see left . Or a projection screen will make a very good reflector , especially if you can adjust its height . Ideally , have one or two purpose - built screens .
الملحق ..
كتاب التصوير الفوتوغرافي
Studio lighting and accessories
Apart from studio flash units ( see p . 150 ) . all artificial studio lighting has either tungsten filament or tungsten - halogen bulbs . Tungsten lamps provide a con stant light independent of the camera , allowing you to select any shutter speed and enabling you to see at a glance the exact effect of your chosen lighting .
Choosing equipment
The kind of studio equipment you should choose will depend on your studio space . For a reasonable sized studio ( not less than 20 ft / 6 m ) , you will probably need two tungsten - halogen lamps - one with a diffused light , and the other with a more concentrated beam . You should have one or two reflector screens which will store easily when not in use . If you cannot afford a background stand , you can use one wall of your studio room instead - as long as it is painted white or a very pale color . A spotlight and a set of multi colored gelatin sheets will turn this sur face into any color you desire . This equipment will provide you with a very efficient basic studio . You can supple ment this by renting extra equipment for special shots . Large professional photo graphic dealers often have a rental de partment where you can borrow almost any kind of lighting equipment , cameras and lenses . It is generally far more economical to rent items of a specialized nature if you only use them on rare occasions .
Bulbs
Tungsten filament bulbs are far brighter than normal domestic types , but they are less durable . The cheapest type , No. 1 photofloods , last only about two hours . Use these with caution because at the beginning and end of their working life their color temperature can be higher than 3,200K ( to which Type B film is balanced ) , making your pictures too warm . No. 2 photofloods last longer - about 100 hours and are constant in color temperature throughout their life . Tungsten - halogen lamps are more expen sive , but they are more powerful and last longer . The introduction of tungsten halogen lamps produced several new types of studio and portable artificial lighting - because tungsten - halogen bulbs are considerably smaller in size than filament bulbs this has enabled the manufacturers to make the whole light source smaller .
Types of lamp
Spotlights use a fresnel lens to produce a strong , concentrated beam of light . You can narrow this beam still more by moving the bulb further away from the concave mirror at the back of the spot . Most modern spots use tungsten - halogen bulbs . You can also buy miniature spots which you use for lighting only small areas of the subject .
Floodlights have wide built - in reflec tors , producing more diffused light . Some have additional mushroom reflec tors in front of the bulb to increase diffusion still further .
Tungsten - halogen bulbs have led to the introduction of several portable floodlights . We use a portable Lowel light for a lot of our work . It is extremely bright but it has a large reflector , so it gives a very diffuse light which covers a large area . The whole lamp folds up into a fairly small suitcase for location work .
Lighting heads
The spotlight , below left , provides a concentrated , narrow , partly - adjustable beam of light suitable for low key studio studies . The floodlight , bottom , has a large reflector , giving a wider beam and softer quality light . The Lowel light , below , has two tungsten - halogen bulbs behind a metal bar which point toward a wide . silvered reflector , making all its bright light indirect and softer in quality .
Portable tungsten lamp This tungsten - halogen lamp operates from a small battery power pack . It provides a very powerful source of light , but unless you fit a diffuser it can be harsh in quality .
Accessories
There are several accessories which modify and control the size or quality of a studio lamp's beam . You can soften light with diffusing screens or umbrellas , and you can use barn doors and snoots to restrict it to a narrow area . With older style lamps you can cut out shapes from black cartridge paper and attach them to the lamp with adhesive tape to restrict or alter the beam ( although this is not possible with modern tungsten - halogen lamps because of the extreme heat that they emit ) .
Reflector screens are very important equipment in a portrait studio and can be placed at any distance from the sitter to provide very effective fill - in . You can make screens by covering large 3 × 7 ft ( 1x2 m ) hinged wooden frames with white cardboard .
Inverse square law
This states that when a light source takes the form of a point , the illumin ation of a surface is inversely propor tional to the square of the distance of that source . When you double this distance the illumination is quartered . To maintain constant exposure while allowing for this effect , increase the aperture by one stop for every doubling of the distance .
Diffusers D You place diffuser screens . far right , between the light and the subject for a softer effect . Umbrellas , right , are made of a soft silvered material . They spread and diffuse individual studio . lights or flash units , giving a shadowless effect .
Lighting accessories A A snoot ( 1 ) narrows the beam of light to light only the hands , for example . You can adjust barn doors ( 2 ) to any position to control the beam of light . Scrims ( 3 ) and half - scrims ( 4 ) reduce the amount of light .
Background paper V " Colorama " papers are the most popular method of achieving an even - colored . plain background . You hang the roll or rolls of paper on a telescopic stand , and pull out the amount you need .
Reflectors An efficient , well - placed reflector screen can do the work of an additional light source . You can use home made or purpose - built screens , see left . Or a projection screen will make a very good reflector , especially if you can adjust its height . Ideally , have one or two purpose - built screens .
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