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الإضاءة ..
كتاب التصوير الفوتوغرافي المغلق
Filtering light
Filters alter the nature of light and are used either to give a more realistic color or tonal rendering to the image or to falsify it ( see p . 132 ) . A filter is usually attached in front of the lens ; by screwing it directly onto the front mounting , inserting it into a lens hood or placing it in a filter holder ( see p . 152 ) . For very close - up work it may be preferable to attach a filter to the back of the lens . The cheapest filters , which are made of gelatine , are easily damaged , so they are best used for experimen tation before buying a more robust glass filter .
For close - ups , I find a polarizing filter is most useful for color and monochrome work . I use it to remove reflections in non - metallic surfaces especially glass and water ; for removing distracting highlights on shiny fruits and leaves ; and for increasing the color saturation of sub jects - especially a blue sky . As the filter is rotated in its mount , the precise effect can be seen by viewing through an SLR camera .
I also always carry a range of blue color correction filters ( 10CC , 20CC and 30CC blue ) to use when photographing blue flowers . Blue flowers are especially difficult to record accur ately on color film , since they reflect some red and infra - red light which our eyes do not detect , but which is recorded as a mauve color on film . A blue CC filter will help to correct this unnatural - looking color , but it will also give a blue cast to any green leaves or grass included in the frame .
Removing reflections
I first took these seaweeds without using any filtration ( bottom right ) . Then I decided to use a polarizing filter to eliminate the distracting skylight reflections on the shiny surface . The picture below left shows the transforma tion of the dominant serrated wrack . The colors of all the seaweeds and also the honeycomb worm reef are greatly enhanced by using this filter . Before exposing any film , I varied the camera angle many times . Lens 55mm micro - Nikkor Mag . on film × 0.16 Mag . on page right × 0.6 ; below x1
Correcting color
The picture above of a raw egg and parsley shows the strong yellow cast which you get when you use daylight film with tungsten lights . I used the same filmstock , Ektachrome 64 daylight , to take the picture on the left together with an 80B ( blue ) color conversion filter . This filter , which is designed for use with daylight color films and tungsten lights , increases the color temperature from 3,400 K to 5,500 ° K , thereby eliminating the yellow cast . I lit the egg using a pair of photofloods each directed through a diffusing screen . Lens 55mm micro - Nikkor Mag . on film * 0.3 Mag . on page above × 0.8 ; left × 3
الإضاءة ..
كتاب التصوير الفوتوغرافي المغلق
Filtering light
Filters alter the nature of light and are used either to give a more realistic color or tonal rendering to the image or to falsify it ( see p . 132 ) . A filter is usually attached in front of the lens ; by screwing it directly onto the front mounting , inserting it into a lens hood or placing it in a filter holder ( see p . 152 ) . For very close - up work it may be preferable to attach a filter to the back of the lens . The cheapest filters , which are made of gelatine , are easily damaged , so they are best used for experimen tation before buying a more robust glass filter .
For close - ups , I find a polarizing filter is most useful for color and monochrome work . I use it to remove reflections in non - metallic surfaces especially glass and water ; for removing distracting highlights on shiny fruits and leaves ; and for increasing the color saturation of sub jects - especially a blue sky . As the filter is rotated in its mount , the precise effect can be seen by viewing through an SLR camera .
I also always carry a range of blue color correction filters ( 10CC , 20CC and 30CC blue ) to use when photographing blue flowers . Blue flowers are especially difficult to record accur ately on color film , since they reflect some red and infra - red light which our eyes do not detect , but which is recorded as a mauve color on film . A blue CC filter will help to correct this unnatural - looking color , but it will also give a blue cast to any green leaves or grass included in the frame .
Removing reflections
I first took these seaweeds without using any filtration ( bottom right ) . Then I decided to use a polarizing filter to eliminate the distracting skylight reflections on the shiny surface . The picture below left shows the transforma tion of the dominant serrated wrack . The colors of all the seaweeds and also the honeycomb worm reef are greatly enhanced by using this filter . Before exposing any film , I varied the camera angle many times . Lens 55mm micro - Nikkor Mag . on film × 0.16 Mag . on page right × 0.6 ; below x1
Correcting color
The picture above of a raw egg and parsley shows the strong yellow cast which you get when you use daylight film with tungsten lights . I used the same filmstock , Ektachrome 64 daylight , to take the picture on the left together with an 80B ( blue ) color conversion filter . This filter , which is designed for use with daylight color films and tungsten lights , increases the color temperature from 3,400 K to 5,500 ° K , thereby eliminating the yellow cast . I lit the egg using a pair of photofloods each directed through a diffusing screen . Lens 55mm micro - Nikkor Mag . on film * 0.3 Mag . on page above × 0.8 ; left × 3
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