The author's guide to controlling the photograph
2001; Elsevier BV; Volume: 85; Issue: 3 Linguagem: Inglês
10.1067/mpr.2001.115085
ISSN1097-6841
Autores Tópico(s)Digital Imaging in Medicine
ResumoPhotographs can convey what words cannot. We depend on photographs to clarify, demonstrate, or enhance our understanding. The myriad choices in photography and electronic technology, however, can present a number of challenges for the clinician or researcher. Some questions that arise are "where do I start, what equipment do I use, and how do I get the photograph electronically to go where it needs to go?" Questions with many answers to choose from. This article is designed to explain roughly the process of photographic reproduction, key elements that can be controlled by the photographer, information on digital processes, and some of the electronic computer language on the "dos and don'ts" of digital reproduction of photographs.The elements for an ideal photograph are correct film, correct light, and correct processing. This sounds simple enough—then why am I getting incorrect color? Why is the picture grainy? Why is the picture blurry? Why is it too light or too dark?Basic mechanicsFig. 2Camera in hand, 200 ASA film.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Fig. 3Camera on tripod, 100 ASA film.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Light plays an important part in the photographic process. The light rays that are emitted from sunlight and artificial light (tungsten light bulbs or fluorescent light) are different. There are 2 types of film—daylight and indoor. These film types are designed with different chemical treatments to handle the different types of light rays. It is important to use the right film type for the right light situation. If daylight film is used to photograph subjects under tungsten lighting, the photograph will have a yellow or reddish tint. Likewise, indoor film used in sunlight will produce a photograph with a bluish or greenish overcast. The flash on a camera is balanced to approximate the properties of daylight. Daylight film is used when a flash is used for the photograph. The use of filters can reproduce "true colors" in some situations. Filters can be purchased at the local camera store and will fit over the camera lens to balance the color properties of the film and light source. If this is chosen, let the camera store personnel know what type of light and the wattage of the bulb being used. This will enable the store personnel to match a filter to your needs.Fig. 4High reflective surface.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Fig. 5Low shutter speed on left; proper shutter speed on right.View Large Image Figure ViewerDownload Hi-res image Download (PPT)A few words need to be said about film processing. You have this perfect picture still inside your camera. The film type and speed selection are correct. The background choice is the right selection for the object selected. The exposure and lighting are correct. You want to see the photograph in print. What is the next step? You take the film to be processed. If the processing of the film is not performed correctly, you may lose that perfect picture. Once the film has been processed, that's it. There is no way to get the perfect picture other than electronic color correction and this is only possible if the film or the print from the film is not too bad. Color correction can be costly because of the time it takes to add, subtract, or balance the color in an image. Because the film is light sensitive, you have to stop the light-film reaction. This is achieved by applying 2 chemicals to the film. A developer is applied to make the image appear. A fixer is then applied to stop the development process (neutralize the developer chemical). Water is used to wash off the excess chemicals, and then the film is dried. The chemistry is used up in the reaction process with the film. Therefore, new chemistry needs to be added and old chemistry needs to be disposed of properly. Too strong or too weak of a chemistry mixture will have disastrous results. Be sure your film is processed by someone who knows what they are doing.The ideal reproductionFig. 6Camera on tripod, 200 ASA film; minimum shadow and good color.View Large Image Figure ViewerDownload Hi-res image Download (PPT)These are some tips that will help you capture an object with natural colors, in focus, and information useful and true-to-life. It is useful to select a camera that has automatic function for f-stop and shutter speed. Consult your local camera store, describe your photographic environment, and they will help you pick the camera for your needs. Use an appropriate film speed, usually 200 to 400 ASA. Match the film type with the light source. Daylight film with the use of a flash should produce a good image. Use the right exposure. Most automatic cameras are set for general purpose use. Minimize the amount of reflected light that can be contaminating the subject. Use neutral backgrounds for a softer surface.Familiarize yourself with the camera that will be used. Experiment with your camera. Take some shots in the environment that is going to be used with the subject or object and document them. Make adjustments as necessary until you get the best photograph. Be consistent with the conditions you use. Make sure your film is processed properly.For the publishing process, send original prints only for reproduction. The preferred size for prints is 3 × 5 in. For consistency, when submitting multiple images, do not mix slides and prints for reproduction, although when submitting slides, a print version should also accompany the slides for orientation of the final illustration.Digital cameras and digital imagesOver the last several years, computer and digital camera technology has advanced tremendously. With all this information, the question now, is how can I use this technology? Sorting out the information can be difficult and misleading.The amateur photographer is often asking several questions: "The color on my monitor looks good. Why doesn't it look the same in print?" "I took the picture with my digital camera. What do you mean the resolution isn't high enough?" "I placed the picture in my word processing program. I sent you my word processing file. Why can't you use it?" "I'm giving you the same picture that I placed on the Internet. I pulled it off the Internet. Why can't you use it?" "All of this stuff is driving me crazy!!!"Let's see if the answers are there.Color spaceElectronic photographs are becoming the new wave. Advances in technology have made the improvements in digital cameras, monitors, scanners, printers, and color correction software a continuing upward trend. However, understanding how to use this new and evolving technology is the issue we have to address.Fig. 7CIE chartView Large Image Figure ViewerDownload Hi-res image Download (PPT)Fig. 8Comparison of different color spaces, human eye versus RGB (monitor) versus CMYK (printed piece).View Large Image Figure ViewerDownload Hi-res image Download (PPT)Monitors have 3 guns (red, green, blue) that produce color. If the monitor is not calibrated, the color balance can be far off. If a person is looking at a photograph on his uncalibrated monitor with fluorescent lights on the west coast, and his publisher is looking at the same photograph on his calibrated monitor in a light-controlled room, there is a very good chance that there is going to be a substantial difference in the viewed color. Also, if the color printer is not profiled, the colors of the viewed photograph will print incorrectly.There are a wide range of color printers on the market. Some have the capabilities of processing good color. But, if they are not calibrated correctly, the color can be incorrect. If the scanner is not profiled, the data for the color will be incorrect. High-end scanners are designed to capture color and detail accurately. However, printing on paper is a reproduction process of what one sees and wants to convey to others.Digital photographyDigital photography can be an asset to the amateur photographer. The only parts of the photographic procedure that are missing are the film and the processing of film. The digital camera captures the image electronically, so the need to process film, get a print made, and then scan the print to an electronic file is eliminated. Historically speaking, digital photography has been viewed as being "inferior" to film-based (conventional) photography. Today, many digital cameras either equal or surpass their film-capture counterparts.Digital camera-sensor technology was developed by and for the scientific and the video camera industries during the 1960s and 1970s. Today the performance of the digital sensors is greater than their performance 10 years ago.There are 2 basic categories of sensors. The area array (square or rectangular) and the linear array (a single line of 1 to 3 rows of light-sensitive devices). Recently, there have been sensors introduced that approach both the size and the resolution of 35-mm film. One such device is the Leaf C-MOST (CMOS) sensor which, from all indications, has a strong promise of being a replacement for 35-mm film as we know it today. CCD (charge coupled devices) are expensive to produce for electronic still digital cameras. CMOS (complementary metal-oxide semiconductor) are sensors usually found in less expensive point-and-shoot digital cameras. They generally have a greater level of "noise" with lower sensitivity to light than their CCD counterparts. There are exceptions to the rule. Film is 100% light sensitive, whereas digital cameras are not 100% sensitive. Because of the way the sensors are built on a grid, only part of the surface of the sensor is actually sensitive to light (about 70%). Digital cameras operate well in light. Some digital cameras have an LCD screen built into the camera so that one can view the object before capturing the image.Electronic image sizesA pixel has no size or shape. It is an electrical charge and is only given size and shape by the device you use to display or print it. If the pixels are squeezed into a smaller area, perceived sharpness increases. Images on high-resolution screens and printouts look sharper only because the available pixels are grouped into a small area, not because there are more pixels. As pixels are enlarged and the image is spread over a larger area, the image's perceived sharpness falls. If enlarged past a certain point, the square pixels will begin to show (the image then becomes pixilated). If an electronic image is going to be used for publication, it should be submitted in the proper format.For example, if a color photographic image is going to be printed at a 5-in. width or less, the electronic file should be 5-in. wide at no less than 300 ppi (pixels per inch). Then, there will be enough color information in the file to produce a good image.The more information captured in an electronic photograph, the better the print quality will be. Most traditional camera stores also sell digital cameras. The staff will help you pick the best camera to fit your needs. If you are going to use a digital photograph for print, set the digital camera to its highest resolution setting. Your file size will be greater, but there will be more image data and your printed piece will show more detail. More image data mean more pixels.Some of the digital cameras give you a large number of pixels when you select SHQ (super-high quality) mode. After an SHQ image is downloaded to your computer, there are a variety of software programs that allow you to check the size and resolution of the image. Depending on the digital camera, an SHQ mode will generally give you a JPEG image 18 in. wide with a resolution of 72 ppi. For reproduction, one needs a file 5-in. wide and 300 ppi. What are you going to do? Your can squeeze pixels but you cannot expand them. Whatever you reduce the width by, you can expand the pixels per inch.Example: 18 in. ÷ 4 = 4.5 in.72 ppi × 4.5 = 288 ppi So a picture 18 in. wide can be reduced by a factor of 4 and the ppi can be raised by a factor of 4.File size/formats for electronic imagesThere are some things one can do to minimize file size and not sacrifice quality. There are a number of compression programs that will reduce the file size. This helps in the speed of transmitting files over the Internet and allows more images to be placed on different media (CDs, Zip disks). There are a number of file formats that can be used to save photographic images. The file size will depend on how much color and detail there is in the image. The more color and detail in the image means the more data that are needed to describe it. Different file formats use different compression schemes. For example, a given CMYK color file is 5.5 in. in width at a resolution of 300 ppi.The EPS format is 4.6 Mb. The EPS format is a drawing format supported by most illustration and page layout programs.The PhotoShop TIFF (tagged-image file format) format is 2 Mb. The TIFF is used to exchange documents between different applications and different computer platforms. The TIFF supports LZW compression. This is the same compression used by the GIF format; however, unlike GIF, LZW TIFF supports image types other than indexed color.Fig. 9Digital 300 ppi image.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Fig. 10Digital 72 ppi imageView Large Image Figure ViewerDownload Hi-res image Download (PPT)Tips on electronic photograph captureExperiment with your digital camera. Start with the automatic settings (they are generally close). Take shots in the environment in which you will be shooting the object or subject. Set the camera to the highest resolution.For publication, send in TIFF or high-quality JPEG format. A resolution of 300 ppi is preferred and images should be at least 5-in. in width.Supplementary Files Download .pdf (.01 MB) Help with pdf files Portuguese PDF Photographs can convey what words cannot. We depend on photographs to clarify, demonstrate, or enhance our understanding. The myriad choices in photography and electronic technology, however, can present a number of challenges for the clinician or researcher. Some questions that arise are "where do I start, what equipment do I use, and how do I get the photograph electronically to go where it needs to go?" Questions with many answers to choose from. This article is designed to explain roughly the process of photographic reproduction, key elements that can be controlled by the photographer, information on digital processes, and some of the electronic computer language on the "dos and don'ts" of digital reproduction of photographs. The elements for an ideal photograph are correct film, correct light, and correct processing. This sounds simple enough—then why am I getting incorrect color? Why is the picture grainy? Why is the picture blurry? Why is it too light or too dark? Basic mechanicsFig. 3Camera on tripod, 100 ASA film.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Light plays an important part in the photographic process. The light rays that are emitted from sunlight and artificial light (tungsten light bulbs or fluorescent light) are different. There are 2 types of film—daylight and indoor. These film types are designed with different chemical treatments to handle the different types of light rays. It is important to use the right film type for the right light situation. If daylight film is used to photograph subjects under tungsten lighting, the photograph will have a yellow or reddish tint. Likewise, indoor film used in sunlight will produce a photograph with a bluish or greenish overcast. The flash on a camera is balanced to approximate the properties of daylight. Daylight film is used when a flash is used for the photograph. The use of filters can reproduce "true colors" in some situations. Filters can be purchased at the local camera store and will fit over the camera lens to balance the color properties of the film and light source. If this is chosen, let the camera store personnel know what type of light and the wattage of the bulb being used. This will enable the store personnel to match a filter to your needs.Fig. 4High reflective surface.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Fig. 5Low shutter speed on left; proper shutter speed on right.View Large Image Figure ViewerDownload Hi-res image Download (PPT)A few words need to be said about film processing. You have this perfect picture still inside your camera. The film type and speed selection are correct. The background choice is the right selection for the object selected. The exposure and lighting are correct. You want to see the photograph in print. What is the next step? You take the film to be processed. If the processing of the film is not performed correctly, you may lose that perfect picture. Once the film has been processed, that's it. There is no way to get the perfect picture other than electronic color correction and this is only possible if the film or the print from the film is not too bad. Color correction can be costly because of the time it takes to add, subtract, or balance the color in an image. Because the film is light sensitive, you have to stop the light-film reaction. This is achieved by applying 2 chemicals to the film. A developer is applied to make the image appear. A fixer is then applied to stop the development process (neutralize the developer chemical). Water is used to wash off the excess chemicals, and then the film is dried. The chemistry is used up in the reaction process with the film. Therefore, new chemistry needs to be added and old chemistry needs to be disposed of properly. Too strong or too weak of a chemistry mixture will have disastrous results. Be sure your film is processed by someone who knows what they are doing. Light plays an important part in the photographic process. The light rays that are emitted from sunlight and artificial light (tungsten light bulbs or fluorescent light) are different. There are 2 types of film—daylight and indoor. These film types are designed with different chemical treatments to handle the different types of light rays. It is important to use the right film type for the right light situation. If daylight film is used to photograph subjects under tungsten lighting, the photograph will have a yellow or reddish tint. Likewise, indoor film used in sunlight will produce a photograph with a bluish or greenish overcast. The flash on a camera is balanced to approximate the properties of daylight. Daylight film is used when a flash is used for the photograph. The use of filters can reproduce "true colors" in some situations. Filters can be purchased at the local camera store and will fit over the camera lens to balance the color properties of the film and light source. If this is chosen, let the camera store personnel know what type of light and the wattage of the bulb being used. This will enable the store personnel to match a filter to your needs. A few words need to be said about film processing. You have this perfect picture still inside your camera. The film type and speed selection are correct. The background choice is the right selection for the object selected. The exposure and lighting are correct. You want to see the photograph in print. What is the next step? You take the film to be processed. If the processing of the film is not performed correctly, you may lose that perfect picture. Once the film has been processed, that's it. There is no way to get the perfect picture other than electronic color correction and this is only possible if the film or the print from the film is not too bad. Color correction can be costly because of the time it takes to add, subtract, or balance the color in an image. Because the film is light sensitive, you have to stop the light-film reaction. This is achieved by applying 2 chemicals to the film. A developer is applied to make the image appear. A fixer is then applied to stop the development process (neutralize the developer chemical). Water is used to wash off the excess chemicals, and then the film is dried. The chemistry is used up in the reaction process with the film. Therefore, new chemistry needs to be added and old chemistry needs to be disposed of properly. Too strong or too weak of a chemistry mixture will have disastrous results. Be sure your film is processed by someone who knows what they are doing. The ideal reproductionThese are some tips that will help you capture an object with natural colors, in focus, and information useful and true-to-life. It is useful to select a camera that has automatic function for f-stop and shutter speed. Consult your local camera store, describe your photographic environment, and they will help you pick the camera for your needs. Use an appropriate film speed, usually 200 to 400 ASA. Match the film type with the light source. Daylight film with the use of a flash should produce a good image. Use the right exposure. Most automatic cameras are set for general purpose use. Minimize the amount of reflected light that can be contaminating the subject. Use neutral backgrounds for a softer surface.Familiarize yourself with the camera that will be used. Experiment with your camera. Take some shots in the environment that is going to be used with the subject or object and document them. Make adjustments as necessary until you get the best photograph. Be consistent with the conditions you use. Make sure your film is processed properly.For the publishing process, send original prints only for reproduction. The preferred size for prints is 3 × 5 in. For consistency, when submitting multiple images, do not mix slides and prints for reproduction, although when submitting slides, a print version should also accompany the slides for orientation of the final illustration. These are some tips that will help you capture an object with natural colors, in focus, and information useful and true-to-life. It is useful to select a camera that has automatic function for f-stop and shutter speed. Consult your local camera store, describe your photographic environment, and they will help you pick the camera for your needs. Use an appropriate film speed, usually 200 to 400 ASA. Match the film type with the light source. Daylight film with the use of a flash should produce a good image. Use the right exposure. Most automatic cameras are set for general purpose use. Minimize the amount of reflected light that can be contaminating the subject. Use neutral backgrounds for a softer surface. Familiarize yourself with the camera that will be used. Experiment with your camera. Take some shots in the environment that is going to be used with the subject or object and document them. Make adjustments as necessary until you get the best photograph. Be consistent with the conditions you use. Make sure your film is processed properly. For the publishing process, send original prints only for reproduction. The preferred size for prints is 3 × 5 in. For consistency, when submitting multiple images, do not mix slides and prints for reproduction, although when submitting slides, a print version should also accompany the slides for orientation of the final illustration. Digital cameras and digital imagesOver the last several years, computer and digital camera technology has advanced tremendously. With all this information, the question now, is how can I use this technology? Sorting out the information can be difficult and misleading.The amateur photographer is often asking several questions: "The color on my monitor looks good. Why doesn't it look the same in print?" "I took the picture with my digital camera. What do you mean the resolution isn't high enough?" "I placed the picture in my word processing program. I sent you my word processing file. Why can't you use it?" "I'm giving you the same picture that I placed on the Internet. I pulled it off the Internet. Why can't you use it?" "All of this stuff is driving me crazy!!!"Let's see if the answers are there.Color spaceElectronic photographs are becoming the new wave. Advances in technology have made the improvements in digital cameras, monitors, scanners, printers, and color correction software a continuing upward trend. However, understanding how to use this new and evolving technology is the issue we have to address.Fig. 8Comparison of different color spaces, human eye versus RGB (monitor) versus CMYK (printed piece).View Large Image Figure ViewerDownload Hi-res image Download (PPT)Monitors have 3 guns (red, green, blue) that produce color. If the monitor is not calibrated, the color balance can be far off. If a person is looking at a photograph on his uncalibrated monitor with fluorescent lights on the west coast, and his publisher is looking at the same photograph on his calibrated monitor in a light-controlled room, there is a very good chance that there is going to be a substantial difference in the viewed color. Also, if the color printer is not profiled, the colors of the viewed photograph will print incorrectly.There are a wide range of color printers on the market. Some have the capabilities of processing good color. But, if they are not calibrated correctly, the color can be incorrect. If the scanner is not profiled, the data for the color will be incorrect. High-end scanners are designed to capture color and detail accurately. However, printing on paper is a reproduction process of what one sees and wants to convey to others. Over the last several years, computer and digital camera technology has advanced tremendously. With all this information, the question now, is how can I use this technology? Sorting out the information can be difficult and misleading. The amateur photographer is often asking several questions: "The color on my monitor looks good. Why doesn't it look the same in print?" "I took the picture with my digital camera. What do you mean the resolution isn't high enough?" "I placed the picture in my word processing program. I sent you my word processing file. Why can't you use it?" "I'm giving you the same picture that I placed on the Internet. I pulled it off the Internet. Why can't you use it?" "All of this stuff is driving me crazy!!!" Let's see if the answers are there. Color spaceElectronic photographs are becoming the new wave. Advances in technology have made the improvements in digital cameras, monitors, scanners, printers, and color correction software a continuing upward trend. However, understanding how to use this new and evolving technology is the issue we have to address.Monitors have 3 guns (red, green, blue) that produce color. If the monitor is not calibrated, the color balance can be far off. If a person is looking at a photograph on his uncalibrated monitor with fluorescent lights on the west coast, and his publisher is looking at the same photograph on his calibrated monitor in a light-controlled room, there is a very good chance that there is going to be a substantial difference in the viewed color. Also, if the color printer is not profiled, the colors of the viewed photograph will print incorrectly.There are a wide range of color printers on the market. Some have the capabilities of processing good color. But, if they are not calibrated correctly, the color can be incorrect. If the scanner is not profiled, the data for the color will be incorrect. High-end scanners are designed to capture color and detail accurately. However, printing on paper is a reproduction process of what one sees and wants to convey to others. Electronic photographs are becoming the new wave. Advances in technology have made the improvements in digital cameras, monitors, scanners, printers, and color correction software a continuing upward trend. However, understanding how to use this new and evolving technology is the issue we have to address. Monitors have 3 guns (red, green, blue) that produce color. If the monitor is not calibrated, the color balance can be far off. If a person is looking at a photograph on his uncalibrated monitor with fluorescent lights on the west coast, and his publisher is looking at the same photograph on his calibrated monitor in a light-controlled room, there is a very good chance that there is going to be a substantial difference in the viewed color. Also, if the color printer is not profiled, the colors of the viewed photograph will print incorrectly. There are a wide range of color printers on the market. Some have the capabilities of processing good color. But, if they are not calibrated correctly, the color can be incorrect. If the scanner is not profiled, the data for the color will be incorrect. High-end scanners are designed to capture color and detail accurately. However, printing on paper is a reproduction process of what one sees and wants to convey to others. Digital photographyDigital photography can be an asset to the amateur photographer. The only parts of the photographic procedure that are missing are the film and the processing of film. The digital camera captures the image electronically, so the need to process film, get a print made, and then scan the print to an electronic file is eliminated. Historically speaking, digital photography has been viewed as being "inferior" to film-based (conventional) photography. Today, many digital cameras either equal or surpass their film-capture counterparts.Digital camera-sensor technology was developed by and for the scientific and the video camera industries during the 1960s and 1970s. Today the performance of the digital sensors is greater than their performance 10 years ago.There are 2 basic categories of sensors. The area array (square or rectangular) and the linear array (a single line of 1 to 3 rows of light-sensitive devices). Recently, there have been sensors introduced that approach both the size and the resolution of 35-mm film. One such device is the Leaf C-MOST (CMOS) sensor which, from all indications, has a strong promise of being a replacement for 35-mm film as we know it today. CCD (charge coupled devices) are expensive to produce for electronic still digital cameras. CMOS (complementary metal-oxide semiconductor) are sensors usually found in less expensive point-and-shoot digital cameras. They generally have a greater level of "noise" with lower sensitivity to light than their CCD counterparts. There are exceptions to the rule. Film is 100% light sensitive, whereas digital cameras are not 100% sensitive. Because of the way the sensors are built on a grid, only part of the surface of the sensor is actually sensitive to light (about 70%). Digital cameras operate well in light. Some digital cameras have an LCD screen built into the camera so that one can view the object before capturing the image. Digital photography can be an asset to the amateur photographer. The only parts of the photographic procedure that are missing are the film and the processing of film. The digital camera captures the image electronically, so the need to process film, get a print made, and then scan the print to an electronic file is eliminated. Historically speaking, digital photography has been viewed as being "inferior" to film-based (conventional) photography. Today, many digital cameras either equal or surpass their film-capture counterparts. Digital camera-sensor technology was developed by and for the scientific and the video camera industries during the 1960s and 1970s. Today the performance of the digital sensors is greater than their performance 10 years ago. There are 2 basic categories of sensors. The area array (square or rectangular) and the linear array (a single line of 1 to 3 rows of light-sensitive devices). Recently, there have been sensors introduced that approach both the size and the resolution of 35-mm film. One such device is the Leaf C-MOST (CMOS) sensor which, from all indications, has a strong promise of being a replacement for 35-mm film as we know it today. CCD (charge coupled devices) are expensive to produce for electronic still digital cameras. CMOS (complementary metal-oxide semiconductor) are sensors usually found in less expensive point-and-shoot digital cameras. They generally have a greater level of "noise" with lower sensitivity to light than their CCD counterparts. There are exceptions to the rule. Film is 100% light sensitive, whereas digital cameras are not 100% sensitive. Because of the way the sensors are built on a grid, only part of the surface of the sensor is actually sensitive to light (about 70%). Digital cameras operate well in light. Some digital cameras have an LCD screen built into the camera so that one can view the object before capturing the image. Electronic image sizesA pixel has no size or shape. It is an electrical charge and is only given size and shape by the device you use to display or print it. If the pixels are squeezed into a smaller area, perceived sharpness increases. Images on high-resolution screens and printouts look sharper only because the available pixels are grouped into a small area, not because there are more pixels. As pixels are enlarged and the image is spread over a larger area, the image's perceived sharpness falls. If enlarged past a certain point, the square pixels will begin to show (the image then becomes pixilated). If an electronic image is going to be used for publication, it should be submitted in the proper format.For example, if a color photographic image is going to be printed at a 5-in. width or less, the electronic file should be 5-in. wide at no less than 300 ppi (pixels per inch). Then, there will be enough color information in the file to produce a good image.The more information captured in an electronic photograph, the better the print quality will be. Most traditional camera stores also sell digital cameras. The staff will help you pick the best camera to fit your needs. If you are going to use a digital photograph for print, set the digital camera to its highest resolution setting. Your file size will be greater, but there will be more image data and your printed piece will show more detail. More image data mean more pixels.Some of the digital cameras give you a large number of pixels when you select SHQ (super-high quality) mode. After an SHQ image is downloaded to your computer, there are a variety of software programs that allow you to check the size and resolution of the image. Depending on the digital camera, an SHQ mode will generally give you a JPEG image 18 in. wide with a resolution of 72 ppi. For reproduction, one needs a file 5-in. wide and 300 ppi. What are you going to do? Your can squeeze pixels but you cannot expand them. Whatever you reduce the width by, you can expand the pixels per inch.Example: 18 in. ÷ 4 = 4.5 in.72 ppi × 4.5 = 288 ppi So a picture 18 in. wide can be reduced by a factor of 4 and the ppi can be raised by a factor of 4. A pixel has no size or shape. It is an electrical charge and is only given size and shape by the device you use to display or print it. If the pixels are squeezed into a smaller area, perceived sharpness increases. Images on high-resolution screens and printouts look sharper only because the available pixels are grouped into a small area, not because there are more pixels. As pixels are enlarged and the image is spread over a larger area, the image's perceived sharpness falls. If enlarged past a certain point, the square pixels will begin to show (the image then becomes pixilated). If an electronic image is going to be used for publication, it should be submitted in the proper format. For example, if a color photographic image is going to be printed at a 5-in. width or less, the electronic file should be 5-in. wide at no less than 300 ppi (pixels per inch). Then, there will be enough color information in the file to produce a good image. The more information captured in an electronic photograph, the better the print quality will be. Most traditional camera stores also sell digital cameras. The staff will help you pick the best camera to fit your needs. If you are going to use a digital photograph for print, set the digital camera to its highest resolution setting. Your file size will be greater, but there will be more image data and your printed piece will show more detail. More image data mean more pixels. Some of the digital cameras give you a large number of pixels when you select SHQ (super-high quality) mode. After an SHQ image is downloaded to your computer, there are a variety of software programs that allow you to check the size and resolution of the image. Depending on the digital camera, an SHQ mode will generally give you a JPEG image 18 in. wide with a resolution of 72 ppi. For reproduction, one needs a file 5-in. wide and 300 ppi. What are you going to do? Your can squeeze pixels but you cannot expand them. Whatever you reduce the width by, you can expand the pixels per inch.Example: 18 in. ÷ 4 = 4.5 in.72 ppi × 4.5 = 288 ppi So a picture 18 in. wide can be reduced by a factor of 4 and the ppi can be raised by a factor of 4. File size/formats for electronic imagesThere are some things one can do to minimize file size and not sacrifice quality. There are a number of compression programs that will reduce the file size. This helps in the speed of transmitting files over the Internet and allows more images to be placed on different media (CDs, Zip disks). There are a number of file formats that can be used to save photographic images. The file size will depend on how much color and detail there is in the image. The more color and detail in the image means the more data that are needed to describe it. Different file formats use different compression schemes. For example, a given CMYK color file is 5.5 in. in width at a resolution of 300 ppi.The EPS format is 4.6 Mb. The EPS format is a drawing format supported by most illustration and page layout programs.The PhotoShop TIFF (tagged-image file format) format is 2 Mb. The TIFF is used to exchange documents between different applications and different computer platforms. The TIFF supports LZW compression. This is the same compression used by the GIF format; however, unlike GIF, LZW TIFF supports image types other than indexed color.Fig. 10Digital 72 ppi imageView Large Image Figure ViewerDownload Hi-res image Download (PPT) There are some things one can do to minimize file size and not sacrifice quality. There are a number of compression programs that will reduce the file size. This helps in the speed of transmitting files over the Internet and allows more images to be placed on different media (CDs, Zip disks). There are a number of file formats that can be used to save photographic images. The file size will depend on how much color and detail there is in the image. The more color and detail in the image means the more data that are needed to describe it. Different file formats use different compression schemes. For example, a given CMYK color file is 5.5 in. in width at a resolution of 300 ppi. The EPS format is 4.6 Mb. The EPS format is a drawing format supported by most illustration and page layout programs. The PhotoShop TIFF (tagged-image file format) format is 2 Mb. The TIFF is used to exchange documents between different applications and different computer platforms. The TIFF supports LZW compression. This is the same compression used by the GIF format; however, unlike GIF, LZW TIFF supports image types other than indexed color. Tips on electronic photograph captureExperiment with your digital camera. Start with the automatic settings (they are generally close). Take shots in the environment in which you will be shooting the object or subject. Set the camera to the highest resolution.For publication, send in TIFF or high-quality JPEG format. A resolution of 300 ppi is preferred and images should be at least 5-in. in width. Experiment with your digital camera. Start with the automatic settings (they are generally close). Take shots in the environment in which you will be shooting the object or subject. Set the camera to the highest resolution. For publication, send in TIFF or high-quality JPEG format. A resolution of 300 ppi is preferred and images should be at least 5-in. in width. Supplementary Files Download .pdf (.01 MB) Help with pdf files Portuguese PDF
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