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A Simple Method of Photomicrography*
NOTES, CASES, INSTRUMENTS A SIMPLE METHOD OF PHOTOMICROGRAPHY* EDWIN S. W R I G H T ,
M.D.
Los Angeles, California At present, photomicrography is usually confined to the larger institutions where costly equipment may be found and special technicians are maintained. Such laboratories frequently use the optical bench to produce the photographs. Good photomicrographs can be taken with relative ease, with a mini mum of equipment, and in little time. Theoretically, all one needs is a microscope
611
the work. However, these cameras are very expensive and not readily available so that for ordinary use a copy attachment has been chosen as the simplest method. The appa ratus chosen has the following advantages: 1. All around usefulness of 35-mm. equip ment. 2. Direct-view focus of the slide. 3. Simplicity of lighting system. 4. Relatively inexpensive equipment. 5. All materials are readily available. 6. Photomicrographs in true color are as easy to take as black and white. 7. The same equipment may be used to
Fig. 1 (Wright). (A) Lens barrel dismounted from camera. (B) Lens mounted in lens plate of copy attachment. (C) Camera back mounted on camera plate of copy attachment. and a camera. Light rays emerging from the ocular of the microscope are parallel, if the observer is emmetropic or rendered so by the proper spectacle lens. When the camera fo cused for infinity is set on top of the micro scope the rays of light should focus exactly on the film. In practice, this method is waste ful of time and film since the observer is rarely exactly emmetropic and the slightest error produces a blurred picture. A focusing apparatus that permits a direct view of the slide to. be photographed is advantageous.
photograph the anterior segment (fig. 3A). The necessary items are: 1. A 35-mm. camera with focal plane shutter. 2. Copy attachment, preferably hinged type. 3. Camera support. 4. Connector. 5. Number-one photoflood bulb in any kind of lamp socket. 6. Ordinary microscope of standard make.
EQUIPMENT
After loading the camera with the desired film, the lens barrel (fig. 1A) is unscrewed from the camera and mounted in the lens plate of the copy attachment (fig. I B ) . The camera back is mounted on the camera-back
The Exacta and other reflex cameras per mit such a direct view and their use speeds * From the Department of Ophthalmology, Northwestern University Medical School.
METHOD
612
NOTES, CASES, INSTRUMENTS
Fig. 2 (Wright). (A) Assembly mounted on support. (B) Focusing with ground-glass image. (C) After focusing, the ground glass is raised and the camera back is lowered into position.
plate of the copy attachment (fig. 1C). The assembly is mounted on the support (fig. 2A). The slide is placed on the stage and roughly focused on the desired area. The camera-copy assembly is gently lowered to the microscope connector and the slide is fo cused by means of the ground glass on the copy attachment (fig. 2B). The ground glass is raised and the camera lowered into its place and the picture made (fig. 2C).
Fig. 3 (Wright). (A) Camera is set up for anterior-segment photography. (B) Shows camera assembly, microscope, and connector.
The light system is a number-one photoflood lamp placed about three feet from the concave mirror of the microscope whose condenser is opened fully and then closed until the light in the field of view just begins to dim. For black and white, using Eastman Super-XX film, about 1/30 of a second is required for a slide of average density. For Kodachrome type-A film, about one-half second of exposure is required. Thin slides require 1/5 second. These slides project nicely. The connector is a short metal tube, or it may simply be a piece of black paper pasted around microscope and camera lens (fig. 3B). It need not be absolutely light tight. Pictures taken with high or low power Tequire the same time of exposure, although the diaphragm of the condenser must be opened wider for high-power photographs. Critical focusing with the ground glass is facilitated by study of the ground-glass pic ture with a hand magnifying lens. 511 South Bonnie Brae.
M.D.
Los Angeles, California At present, photomicrography is usually confined to the larger institutions where costly equipment may be found and special technicians are maintained. Such laboratories frequently use the optical bench to produce the photographs. Good photomicrographs can be taken with relative ease, with a mini mum of equipment, and in little time. Theoretically, all one needs is a microscope
611
the work. However, these cameras are very expensive and not readily available so that for ordinary use a copy attachment has been chosen as the simplest method. The appa ratus chosen has the following advantages: 1. All around usefulness of 35-mm. equip ment. 2. Direct-view focus of the slide. 3. Simplicity of lighting system. 4. Relatively inexpensive equipment. 5. All materials are readily available. 6. Photomicrographs in true color are as easy to take as black and white. 7. The same equipment may be used to
Fig. 1 (Wright). (A) Lens barrel dismounted from camera. (B) Lens mounted in lens plate of copy attachment. (C) Camera back mounted on camera plate of copy attachment. and a camera. Light rays emerging from the ocular of the microscope are parallel, if the observer is emmetropic or rendered so by the proper spectacle lens. When the camera fo cused for infinity is set on top of the micro scope the rays of light should focus exactly on the film. In practice, this method is waste ful of time and film since the observer is rarely exactly emmetropic and the slightest error produces a blurred picture. A focusing apparatus that permits a direct view of the slide to. be photographed is advantageous.
photograph the anterior segment (fig. 3A). The necessary items are: 1. A 35-mm. camera with focal plane shutter. 2. Copy attachment, preferably hinged type. 3. Camera support. 4. Connector. 5. Number-one photoflood bulb in any kind of lamp socket. 6. Ordinary microscope of standard make.
EQUIPMENT
After loading the camera with the desired film, the lens barrel (fig. 1A) is unscrewed from the camera and mounted in the lens plate of the copy attachment (fig. I B ) . The camera back is mounted on the camera-back
The Exacta and other reflex cameras per mit such a direct view and their use speeds * From the Department of Ophthalmology, Northwestern University Medical School.
METHOD
612
NOTES, CASES, INSTRUMENTS
Fig. 2 (Wright). (A) Assembly mounted on support. (B) Focusing with ground-glass image. (C) After focusing, the ground glass is raised and the camera back is lowered into position.
plate of the copy attachment (fig. 1C). The assembly is mounted on the support (fig. 2A). The slide is placed on the stage and roughly focused on the desired area. The camera-copy assembly is gently lowered to the microscope connector and the slide is fo cused by means of the ground glass on the copy attachment (fig. 2B). The ground glass is raised and the camera lowered into its place and the picture made (fig. 2C).
Fig. 3 (Wright). (A) Camera is set up for anterior-segment photography. (B) Shows camera assembly, microscope, and connector.
The light system is a number-one photoflood lamp placed about three feet from the concave mirror of the microscope whose condenser is opened fully and then closed until the light in the field of view just begins to dim. For black and white, using Eastman Super-XX film, about 1/30 of a second is required for a slide of average density. For Kodachrome type-A film, about one-half second of exposure is required. Thin slides require 1/5 second. These slides project nicely. The connector is a short metal tube, or it may simply be a piece of black paper pasted around microscope and camera lens (fig. 3B). It need not be absolutely light tight. Pictures taken with high or low power Tequire the same time of exposure, although the diaphragm of the condenser must be opened wider for high-power photographs. Critical focusing with the ground glass is facilitated by study of the ground-glass pic ture with a hand magnifying lens. 511 South Bonnie Brae.