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تقنية الكاميرا .. المرشد خطوة بخطوة للتصوير الفوتوغرافي
CAMERA TECHNIQUE
STEP 1 : The simple camera
STEP 2 : Camera controls
STEP 3 : Controlling picture sharpness
STEP 4 : Film and measuring exposure
This first main section introduces you to the basic tools and materials of photography , and establishes fundamental camera- handling skills . It draws directly on the principles of image- forming and light - sensitivity discussed on pages 16-22 . Starting with the simplest kind of modern camera , it progresses to the popular single lens reflex type . Each camera control is looked at in turn , to see what it contributes to practical picture making . Combining the various controls leads on to choosing film and the measurement and control of exposure .
You need not have a darkroom , or do your own processing , or even have any knowledge of how cameras work , before starting this section . If you are an absolute beginner , it is the most important technical part of the book . It explains and establishes all the terms such as f number , depth of field , and exposure - that you will meet regularly in later sections . If you already have some experience with a camera , use the section as a refresher course to check your knowledge .
Work through the material page by page , because terms are explained as introduced , and lead on one from another . Don't limit your learning to reading . Test out the statements made and tackle some of the assignments . You will find it much more interesting and instructional if you take pictures as you go along . All you need is a camera with a normal lens , some form of exposure meter , and a reasonable supply of black and white film . ( You will not be dealing with taking pictures in color until later , on pages 141-58 . )
You must expect to use a fair amount of film to begin with as it will take practice to be able to predict your results accurately . You will be making comparison pictures , experimenting - and inevitably making mistakes . It is important to practice as much as you can , so that you have some practical results for comparison . You will see and remember the points this book is making much better if they appear in your own pictures .
Think carefully before composing and making the settings for every shot . What effect are you trying to achieve ? Perhaps you are comparing the results of different settings ; or applying a technique to a particular subject ; or ( and this is equally important ) breaking the rules to see what visual effect will occur . Get into the habit of taking several versions , perhaps making notes so you can remember the settings . Have the film processed and printed promptly , and learn to assess your results critically along with the notes you have made .
- Don't expect perfect results at this stage . Your early efforts will be in the nature of exercises . Concentrate on learning from your mistakes as well as your successes . Keep to simple subjects at first , and avoid difficult lighting conditions such as extreme contrasts between highlights and shadows or dim indoor conditions . Your main aim should be to get comfortable with your camera , and familiar with its controls . Only then can you begin to " work through the camera " and respond freely to your subject matter and lighting conditions .
Arrangement of steps :
The section begins by looking at a cheap simple camera , because this has all the essential controls - lens , shutter and viewfinder- in their most basic form . You must still learn to load the film in the same way , and with the same accuracy and speed , as with other more expensive cameras . But simple camera settings for lens and shutter are either fixed , or have a very narrow range . This makes the camera uncomplicated and quick to use .
This very lack of control soon becomes frustrating , however . You will want to be able to work closer to your subject , to take pictures under all sorts of lighting conditions , or to emphasize one part of a picture by making everything else unsharp . For this you need a wider choice of lens and shutter settings . So the next step moves on to a more elaborate camera which offers much - more flexibility – with fully variable lens , aperture and shutter . Here the single lens reflex type of 35 mm camera is mainly featured because of its popularity and comparative simplicity .
With a single lens reflex camera , such as a Pentax , Nikon , Minolta or Canon , you can predict the appearance of your photographs with great accuracy , because you view the actual image formed by the taking lens . These cameras each form the basis of a system - a whole range of lenses and accessories which you can build up as your experience of photography grows .
The 35 mm single lens reflex camera is therefore the principal camera used throughout the book . But although most diagrams show this sort of camera , the information is valid for other cameras too . If for example you own a larger camera , perhaps a twin lens reflex , or a good non - reflex 35 mm camera , you can work through the book just as well . Most of the principles discussed apply equally to all camera types . Where their mechanical or optical arrangements differ , these will be shown . ( You will find details of other camera types , such as a twin lens reflex , in the Appendix , on pages 204-10 . )
Reading over this section should enable you to identify all the controls on whatever camera you possess , and see how they each alter your results . The first control is the focusing ring on the lens . As you have already seen on pages 20-1 , focusing a lens has a similar effect to focusing the eye . Cameras use various devices to show you which parts of the scene are being sharply focused . On some you just set the subject to camera distance on a scale . Others show you a double picture in the viewfinder , until the focus is set properly . Best of all are cameras with focusing screens that show you how the image actually looks - which different parts are sharp or unsharp , and what the overall effect will be . The single lens reflex is one such camera .
This section and the next deal only with the " normal " lens- the one usually sold with the camera and accepted as giving a view most similar to the eye . ( Other lenses are introduced on pages 92-9 . ) On a 35 mm camera a normal lens has a focal length of about 50 or 55 mm . If your camera is larger or smaller than this , the " normal " focal length is scaled up or down . For example , 80 mm for a 2 ins square rollfilm camera , and 25 mm for a 110 pocket camera .
The second camera control you are introduced to is the lens aperture . This follows on from focusing , partly because it is often placed right next to the focusing ring on a camera , but mostly because it also affects sharpness in your pictures . The aperture setting controls the amount of light entering the camera . To control aperture , you must get used to a scale of " numbers " , and understand how different settings will affect the amount of the scene rendered sharp at one focusing distance . It helps if you can actually see the effect of altering aperture on your viewing screen . Here again a single lens reflex camera is the best .
The third control introduced in the shutter . You are probably quite familiar with this control , because no camera is without it . Shutter determines when , and for how long , film is exposed to light . The speed you select has some interesting effects on the way moving subjects ( or movements of the camera ) are recorded in your photographs .
Aperture and shutter together control exposure - the total quantity of light given to your film . One alters the amount , or " intensity " , of light admitted , the other the time that light is allowed to act . Many beginners in photography are worried by having to judge correct exposure . But it is surprisingly straightforward , as a rule . Modern light - reading meters can be very accurate , and variations from correct settings may still give acceptable results on today's black and white film . ( Color film requires greater accuracy . ) The important thing is to know how to make readings as quickly and accurately as possible , and what sort of visual effects you can achieve by giving deliberate over - or underexposure to particular subjects .
CAMERA TECHNIQUE
STEP 1 : The simple camera
STEP 2 : Camera controls
STEP 3 : Controlling picture sharpness
STEP 4 : Film and measuring exposure
This first main section introduces you to the basic tools and materials of photography , and establishes fundamental camera- handling skills . It draws directly on the principles of image- forming and light - sensitivity discussed on pages 16-22 . Starting with the simplest kind of modern camera , it progresses to the popular single lens reflex type . Each camera control is looked at in turn , to see what it contributes to practical picture making . Combining the various controls leads on to choosing film and the measurement and control of exposure .
You need not have a darkroom , or do your own processing , or even have any knowledge of how cameras work , before starting this section . If you are an absolute beginner , it is the most important technical part of the book . It explains and establishes all the terms such as f number , depth of field , and exposure - that you will meet regularly in later sections . If you already have some experience with a camera , use the section as a refresher course to check your knowledge .
Work through the material page by page , because terms are explained as introduced , and lead on one from another . Don't limit your learning to reading . Test out the statements made and tackle some of the assignments . You will find it much more interesting and instructional if you take pictures as you go along . All you need is a camera with a normal lens , some form of exposure meter , and a reasonable supply of black and white film . ( You will not be dealing with taking pictures in color until later , on pages 141-58 . )
You must expect to use a fair amount of film to begin with as it will take practice to be able to predict your results accurately . You will be making comparison pictures , experimenting - and inevitably making mistakes . It is important to practice as much as you can , so that you have some practical results for comparison . You will see and remember the points this book is making much better if they appear in your own pictures .
Think carefully before composing and making the settings for every shot . What effect are you trying to achieve ? Perhaps you are comparing the results of different settings ; or applying a technique to a particular subject ; or ( and this is equally important ) breaking the rules to see what visual effect will occur . Get into the habit of taking several versions , perhaps making notes so you can remember the settings . Have the film processed and printed promptly , and learn to assess your results critically along with the notes you have made .
- Don't expect perfect results at this stage . Your early efforts will be in the nature of exercises . Concentrate on learning from your mistakes as well as your successes . Keep to simple subjects at first , and avoid difficult lighting conditions such as extreme contrasts between highlights and shadows or dim indoor conditions . Your main aim should be to get comfortable with your camera , and familiar with its controls . Only then can you begin to " work through the camera " and respond freely to your subject matter and lighting conditions .
Arrangement of steps :
The section begins by looking at a cheap simple camera , because this has all the essential controls - lens , shutter and viewfinder- in their most basic form . You must still learn to load the film in the same way , and with the same accuracy and speed , as with other more expensive cameras . But simple camera settings for lens and shutter are either fixed , or have a very narrow range . This makes the camera uncomplicated and quick to use .
This very lack of control soon becomes frustrating , however . You will want to be able to work closer to your subject , to take pictures under all sorts of lighting conditions , or to emphasize one part of a picture by making everything else unsharp . For this you need a wider choice of lens and shutter settings . So the next step moves on to a more elaborate camera which offers much - more flexibility – with fully variable lens , aperture and shutter . Here the single lens reflex type of 35 mm camera is mainly featured because of its popularity and comparative simplicity .
With a single lens reflex camera , such as a Pentax , Nikon , Minolta or Canon , you can predict the appearance of your photographs with great accuracy , because you view the actual image formed by the taking lens . These cameras each form the basis of a system - a whole range of lenses and accessories which you can build up as your experience of photography grows .
The 35 mm single lens reflex camera is therefore the principal camera used throughout the book . But although most diagrams show this sort of camera , the information is valid for other cameras too . If for example you own a larger camera , perhaps a twin lens reflex , or a good non - reflex 35 mm camera , you can work through the book just as well . Most of the principles discussed apply equally to all camera types . Where their mechanical or optical arrangements differ , these will be shown . ( You will find details of other camera types , such as a twin lens reflex , in the Appendix , on pages 204-10 . )
Reading over this section should enable you to identify all the controls on whatever camera you possess , and see how they each alter your results . The first control is the focusing ring on the lens . As you have already seen on pages 20-1 , focusing a lens has a similar effect to focusing the eye . Cameras use various devices to show you which parts of the scene are being sharply focused . On some you just set the subject to camera distance on a scale . Others show you a double picture in the viewfinder , until the focus is set properly . Best of all are cameras with focusing screens that show you how the image actually looks - which different parts are sharp or unsharp , and what the overall effect will be . The single lens reflex is one such camera .
This section and the next deal only with the " normal " lens- the one usually sold with the camera and accepted as giving a view most similar to the eye . ( Other lenses are introduced on pages 92-9 . ) On a 35 mm camera a normal lens has a focal length of about 50 or 55 mm . If your camera is larger or smaller than this , the " normal " focal length is scaled up or down . For example , 80 mm for a 2 ins square rollfilm camera , and 25 mm for a 110 pocket camera .
The second camera control you are introduced to is the lens aperture . This follows on from focusing , partly because it is often placed right next to the focusing ring on a camera , but mostly because it also affects sharpness in your pictures . The aperture setting controls the amount of light entering the camera . To control aperture , you must get used to a scale of " numbers " , and understand how different settings will affect the amount of the scene rendered sharp at one focusing distance . It helps if you can actually see the effect of altering aperture on your viewing screen . Here again a single lens reflex camera is the best .
The third control introduced in the shutter . You are probably quite familiar with this control , because no camera is without it . Shutter determines when , and for how long , film is exposed to light . The speed you select has some interesting effects on the way moving subjects ( or movements of the camera ) are recorded in your photographs .
Aperture and shutter together control exposure - the total quantity of light given to your film . One alters the amount , or " intensity " , of light admitted , the other the time that light is allowed to act . Many beginners in photography are worried by having to judge correct exposure . But it is surprisingly straightforward , as a rule . Modern light - reading meters can be very accurate , and variations from correct settings may still give acceptable results on today's black and white film . ( Color film requires greater accuracy . ) The important thing is to know how to make readings as quickly and accurately as possible , and what sort of visual effects you can achieve by giving deliberate over - or underexposure to particular subjects .
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