تويت
التصوير المجهري ..
مؤثرات خاصة ..
كتاب التصوير الفوتوغرافي المغلق
Photomicrography
This book covers ways and means of taking close - up pictures using a conventional camera system and extension tubes or bellows . With the exception of true macro lenses ( see p . 148 ) , it is difficult to take pictures at much greater than 10 life - size without using a microscope . Photomicrography is the production of images by means of a microscope . This very specialized aspect of photography is really beyond the scope of this book , but a few pictures have been included to illustrate what this field offers beyond the close - up range .
Any 35mm SLR camera can be used to take photomicrographs , although a model with TTL metering will make exposure determination much easier if you do not have a special micro scope exposure meter . Since magnification and focusing of the image are both done by the microscope , the lens is removed from the body of the camera which is then connected to the microscope above the eye piece by means of a light - excluding adapter . Some microscopes have optional film backs - a few for Polaroid instant film - which do away with the need for a camera body altogether . Without a camera viewfinder , the image is then focused onto an eye piece at right angles to the film back . In addition to the microscope itself , you will need petri dishes , microscope slides and glass cover slips . As for close - ups , the type and direction of the light source should be selected to suit the subject . If the microscope does not have built - in illumination , you will need to use a small - beamed light source such as a micro scope lamp ( see p . 157 ) for stationary subjects , or fiber optics ( see p . 52 ) or an electronic flash for moving subjects .
To illuminate a specimen by bright field transmitted light , the light is shone onto a small , circular , adjustable mirror so that it passes up to the specimen on the stage via the sub - stage condenser . Dark field transmitted light is achieved by placing a circular glass disk with a black center ( known as a dark field stop ) beneath the condenser . Like the dark field illumination for larger subjects described on page 54 , this illuminates a translucent specimen so that it appears to glow against a dark back ground . Opaque specimens have to be lit from above , and fiber optics provide a convenient localized light source .
Creative color photomicrographs are achieved with filters . A pair of polarizing screens cari produce color abstracts of crystals .
Closed stomata
To show the pores or stomata of leaf among the leaf cells . I peeled off the outer layer of a Tradescantia leaf in the evening at 9 p.m. and laid it on a clean microscope slide . Using bright field illumination , the cell walls surrounding each cell showed up clearly . In this picture , six pairs of swollen guard cells can be seen closing the stomatal openings thus preventing water loss into the atmosphere . Microscope Wild M20 Mag . on film × 50 Mag . on page × 125
◄ Open stomata
I wanted to take a comparative picture of the Tradescantia leaf showing the stomata open . To do this . I peeled off the outer leaf layer at 8 a.m. on the following morning . The lighting was exactly the same as in the picture above . Early in the morning the guard cells contract , opening the stomata to allow gaseous exchange to take place . Microscope Wild M20 Mag . on film × 50 Mag . on page × 125
Photographic grain
I used a small portion of a negative from a Royal X Pan film which I had up - rated to 1250 ASA . I photographed it by bright field illumination down a microscope . At this magnification the grains of black metallic silver which comprise the image can be seen . Microscope Wild M20 Mag . on film x30 Mag . on page × 60
Pollen grains ▷ When ripe Korean fir cones were shedding their microscopic pollen grains , I sprinkled a thin layer onto a microscope slide which I lit by dark field illumination . The pair of air sacs on each grain can be clearly seen . Microscope Wild M20 Mag . on film x30 Mag . on page × 180
Starch grains A To get some starch grains I cut a raw potato in half rubbed it onto a microscope slide and added a few drops of iodine . Dark field illumination was used to rim light the grains . Microscope Wild M20 Mag . on film × 50 Mag . on page × 200
Etching detail ▷ In a book published in 1802 , I found an etching of a lizard . I used a stereo microscope to photograph the lizard's eye lit with a single fiber optic . Microscope Wild Photo makroskop M400 Mag . on film × 16 Mag . on page x48
Using transillumination to reveal structure
I collected a dead pearl - bordered fritillary and placed one of its wings on a glass microscope slide . By lighting it from below , I was able to show the way in which each colored scale overlaps the two scales beneath it . Microscope Wild M20 Mag . on film × 50 Mag . on page 125
مؤثرات خاصة ..
كتاب التصوير الفوتوغرافي المغلق
Photomicrography
This book covers ways and means of taking close - up pictures using a conventional camera system and extension tubes or bellows . With the exception of true macro lenses ( see p . 148 ) , it is difficult to take pictures at much greater than 10 life - size without using a microscope . Photomicrography is the production of images by means of a microscope . This very specialized aspect of photography is really beyond the scope of this book , but a few pictures have been included to illustrate what this field offers beyond the close - up range .
Any 35mm SLR camera can be used to take photomicrographs , although a model with TTL metering will make exposure determination much easier if you do not have a special micro scope exposure meter . Since magnification and focusing of the image are both done by the microscope , the lens is removed from the body of the camera which is then connected to the microscope above the eye piece by means of a light - excluding adapter . Some microscopes have optional film backs - a few for Polaroid instant film - which do away with the need for a camera body altogether . Without a camera viewfinder , the image is then focused onto an eye piece at right angles to the film back . In addition to the microscope itself , you will need petri dishes , microscope slides and glass cover slips . As for close - ups , the type and direction of the light source should be selected to suit the subject . If the microscope does not have built - in illumination , you will need to use a small - beamed light source such as a micro scope lamp ( see p . 157 ) for stationary subjects , or fiber optics ( see p . 52 ) or an electronic flash for moving subjects .
To illuminate a specimen by bright field transmitted light , the light is shone onto a small , circular , adjustable mirror so that it passes up to the specimen on the stage via the sub - stage condenser . Dark field transmitted light is achieved by placing a circular glass disk with a black center ( known as a dark field stop ) beneath the condenser . Like the dark field illumination for larger subjects described on page 54 , this illuminates a translucent specimen so that it appears to glow against a dark back ground . Opaque specimens have to be lit from above , and fiber optics provide a convenient localized light source .
Creative color photomicrographs are achieved with filters . A pair of polarizing screens cari produce color abstracts of crystals .
Closed stomata
To show the pores or stomata of leaf among the leaf cells . I peeled off the outer layer of a Tradescantia leaf in the evening at 9 p.m. and laid it on a clean microscope slide . Using bright field illumination , the cell walls surrounding each cell showed up clearly . In this picture , six pairs of swollen guard cells can be seen closing the stomatal openings thus preventing water loss into the atmosphere . Microscope Wild M20 Mag . on film × 50 Mag . on page × 125
◄ Open stomata
I wanted to take a comparative picture of the Tradescantia leaf showing the stomata open . To do this . I peeled off the outer leaf layer at 8 a.m. on the following morning . The lighting was exactly the same as in the picture above . Early in the morning the guard cells contract , opening the stomata to allow gaseous exchange to take place . Microscope Wild M20 Mag . on film × 50 Mag . on page × 125
Photographic grain
I used a small portion of a negative from a Royal X Pan film which I had up - rated to 1250 ASA . I photographed it by bright field illumination down a microscope . At this magnification the grains of black metallic silver which comprise the image can be seen . Microscope Wild M20 Mag . on film x30 Mag . on page × 60
Pollen grains ▷ When ripe Korean fir cones were shedding their microscopic pollen grains , I sprinkled a thin layer onto a microscope slide which I lit by dark field illumination . The pair of air sacs on each grain can be clearly seen . Microscope Wild M20 Mag . on film x30 Mag . on page × 180
Starch grains A To get some starch grains I cut a raw potato in half rubbed it onto a microscope slide and added a few drops of iodine . Dark field illumination was used to rim light the grains . Microscope Wild M20 Mag . on film × 50 Mag . on page × 200
Etching detail ▷ In a book published in 1802 , I found an etching of a lizard . I used a stereo microscope to photograph the lizard's eye lit with a single fiber optic . Microscope Wild Photo makroskop M400 Mag . on film × 16 Mag . on page x48
Using transillumination to reveal structure
I collected a dead pearl - bordered fritillary and placed one of its wings on a glass microscope slide . By lighting it from below , I was able to show the way in which each colored scale overlaps the two scales beneath it . Microscope Wild M20 Mag . on film × 50 Mag . on page 125
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