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كتاب التصوير الفوتوغرافي المغلق
Bellows
Bellows extend the lens further away from the camera than extension tubes , to give greater magnifications ( up to x 3.5 with a 50mm lens ) . The concertina fabric construction also pro vides a continuously variable magnification . The cheapest bellows units are non - automatic and simply move the lens backwards or for wards . On more expensive units , both the front and back of the bellows can be adjusted , while a separate focusing rail serves as a focus ing slide ( see p . 152 ) . Once the magnification has been set on the bellows ( by moving them so the required amount of extension reads off the millimeter scale ) , the whole unit - camera , bel lows and lens - can be moved forwards or back wards on the focusing rail until the subject appears in focus . Greater magnifications and better definition will be gained if you mount the lens in the reverse position by using a reversing ring ( see p . 148 ) .
A few bellows units , including the Nikon PB4 , have additional movements which allow the front end to be shifted 10mm to the left or right and also pivoted through 25 ° , which can be useful when taking close - ups of an object at an angle to the film plane . Like automatic extension tubes ( see p . 22 ) , auto bellows stop down the lens to the preselected aperture . Non auto bellows can either be stopped down manually or automatically by using a double cable release ( see p . 148 ) which closes the lens diaphragm just before the shutter is fired .
When bellows are used with TTL cameras , direct TTL readings can be made , although with some units the lens must first be stopped down to the chosen aperture .
Color printing ▷ When a printed color plate in a magazine or book is viewed with a strong magnifying glass , you see a mass of tiny colored dots . It is the relative size of each colored dot which is the intrinsic factor in recreating a replica of the original color transparency . To achieve this , I used a color proof of a picture of a dormouse . I cut out the head , scotch taped it to a flat surface below an overhead camera and lit it with a single flash and a reflector . The dots represent the nose of the dormouse and the base of the whiskers . Lens Leitz 12.5mm Photar + bellows Mag . on film × 10 Mag . on page × 25
Nylon pantie hose ▷ I cut out a square from some old pantie hose , stretched it over a piece of glass and held it in position with scotch tape . Dark field illumination ( see p . 54 ) was used to show up the characteristic kinky strands of stretched nylon . Lens Leitz 25mm Photar + bellows Mag . on film × 6 Mag . on page × 15
Nettle hairs I used dark field . illumination ( see p . 54 ) to highlight the structure of the needle - like hairs on the stem of a stinging nettle . It is the sap contained within the swollen base of these hairs which causes the swelling and pain of a nettle rash . Lens 55mm micro - Nikkor + bellows Mag . on film x3 Mag . on page × 12
Nikon bellows unit on macro copy stand .
Butterfly scales Many butterfly and moth wings sport false ' eyes ' which serve to alarm a potential predator . When these eye - spots are enlarged , it is easy to see how they are made up from different colored wing scales arranged in such a way that they produce a distinctive pattern for each particular species . Here I photographed with a single flash a pinned specimen collected from Guiana . Lens Hasselblad 80mm + bellows Mag . on film x3 Mag . on page x8
التشريح عن قرب ..
كتاب التصوير الفوتوغرافي المغلق
Bellows
Bellows extend the lens further away from the camera than extension tubes , to give greater magnifications ( up to x 3.5 with a 50mm lens ) . The concertina fabric construction also pro vides a continuously variable magnification . The cheapest bellows units are non - automatic and simply move the lens backwards or for wards . On more expensive units , both the front and back of the bellows can be adjusted , while a separate focusing rail serves as a focus ing slide ( see p . 152 ) . Once the magnification has been set on the bellows ( by moving them so the required amount of extension reads off the millimeter scale ) , the whole unit - camera , bel lows and lens - can be moved forwards or back wards on the focusing rail until the subject appears in focus . Greater magnifications and better definition will be gained if you mount the lens in the reverse position by using a reversing ring ( see p . 148 ) .
A few bellows units , including the Nikon PB4 , have additional movements which allow the front end to be shifted 10mm to the left or right and also pivoted through 25 ° , which can be useful when taking close - ups of an object at an angle to the film plane . Like automatic extension tubes ( see p . 22 ) , auto bellows stop down the lens to the preselected aperture . Non auto bellows can either be stopped down manually or automatically by using a double cable release ( see p . 148 ) which closes the lens diaphragm just before the shutter is fired .
When bellows are used with TTL cameras , direct TTL readings can be made , although with some units the lens must first be stopped down to the chosen aperture .
Color printing ▷ When a printed color plate in a magazine or book is viewed with a strong magnifying glass , you see a mass of tiny colored dots . It is the relative size of each colored dot which is the intrinsic factor in recreating a replica of the original color transparency . To achieve this , I used a color proof of a picture of a dormouse . I cut out the head , scotch taped it to a flat surface below an overhead camera and lit it with a single flash and a reflector . The dots represent the nose of the dormouse and the base of the whiskers . Lens Leitz 12.5mm Photar + bellows Mag . on film × 10 Mag . on page × 25
Nylon pantie hose ▷ I cut out a square from some old pantie hose , stretched it over a piece of glass and held it in position with scotch tape . Dark field illumination ( see p . 54 ) was used to show up the characteristic kinky strands of stretched nylon . Lens Leitz 25mm Photar + bellows Mag . on film × 6 Mag . on page × 15
Nettle hairs I used dark field . illumination ( see p . 54 ) to highlight the structure of the needle - like hairs on the stem of a stinging nettle . It is the sap contained within the swollen base of these hairs which causes the swelling and pain of a nettle rash . Lens 55mm micro - Nikkor + bellows Mag . on film x3 Mag . on page × 12
Nikon bellows unit on macro copy stand .
Butterfly scales Many butterfly and moth wings sport false ' eyes ' which serve to alarm a potential predator . When these eye - spots are enlarged , it is easy to see how they are made up from different colored wing scales arranged in such a way that they produce a distinctive pattern for each particular species . Here I photographed with a single flash a pinned specimen collected from Guiana . Lens Hasselblad 80mm + bellows Mag . on film x3 Mag . on page x8
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