Learn the Ropes of Digital Photography
By David Peters
Most photographs aren't just well-defined black and white boundaries - in fact, none of them are. So when faced with angles, gradients, or irregular shapes, the computer has to use its stored rules to guess what color the new pixels should be. In theory, the better routines allow the computer to do a pretty good job at smoothing out the image when the resolution is increased and all those new pixels are put in place. In practice, unlike in the movies or on TV, you can't get information out of a picture that isn't there. That tiny black dot on the horizon isn't going to turn into an umbrella when you double the resolution, it will just be a bigger black dot. So if you need a "bigger picture" than you have, why not use interpolation? The trick is that the interpolation done in your camera is not the same as the interpolation done in your computer's editing software.
You can recreate the settings of a favorite shot or repeat a favorite effect, and higher-level information such as special lenses and light metering modes can be invaluable as you advance your knowledge of photography. You can even share this information with friends or colleagues to help duplicate tricky shots, or create a database or spreadsheet of the effects of specific settings to help you recreate effects or types of shots under different conditions. An example would be keeping track of how white balance changes affect the appearance of particular colors. Instead of making notes of what changes you made and what order photos were taken in (particularly when the string of photos were all taken of the same scene), you can skip the notes and compare the settings in the EXIF data instead. Then, when you work on your log, you can copy setting information over and just make a note about which settings worked best.
Rough Side of RAW: RAW formats differ from camera to camera and there are debates about camera programming that provides some control over your RAW files by the camera manufacturer. Where protests have been issued, there is an effort to provide standardized RAW formats that would better serve the consumer where general market software could be used to edit the RAW material. If your computer is equipped with lots of processing memory, RAW data will not be as much a problem, however presently, RAW files take a lot more time to open and process than JPEG and TIFF files. That is where the option to capture in RAW and JPEG simultaneously is a strong benefit. While standard editing software is now offered on the market, the way that software processes RAW files may differ depending on how the software from the manufacturer is recognized by the software. Thus, be sure to find and ask a savvy sales expert. Most sensors record light over a 12-bit range, with intensities of more or less 4096 possible values. Each sensor with 12-bit output is one and a half bytes. So our small chip with 20,000 light cells gives a raw output of 30,000 bytes. In an actual file there is some non-image information, but that can be ignored for simple calculations.
Analog or film cameras use the term ASA speed, however it is important to remember that a single digital camera can capture and store images at several ISO speeds. Amplifying the image signal in a camera can also amplify noise and thereby higher ISO speeds may produce progressively more noise in the photo. The character of an image in a photo can also change noise. Where lighter areas in analog or film photos tend to have the most noise, it is the darker areas of digital photographs that have the largest amount of noise. Digital cameras produce three types of noise called random noise, fixed pattern noise and banding noise. Random noise describes the abnormal intensity of color fluctuations compared to the rest of the photograph. It is most influenced by the ISO speed however the pattern of random noise may change even if exposure settings remain the same. Random noise may be the least objectionable, but the most difficult to remove where the noise is too often mistaken for true image characteristics. Fixed Hot pixels or fixed pattern noise describe pixel intensity that far exceeds that of ambient random noise fluctuations.
If you are looking to turn your pictures into pieces of art, there are many options available to you, as well. You can turn your print into a black and white picture and hand color some details. You can create beautiful special effects that will really make your digital photo stand out in a crowd, too. As you can image, the tools to create the perfect picture can cost a lot of money, if you have to purchase them. If you are on a budget, or just like to save money, anything you can find for free is a bonus! Well, there are free photo editors out there, you just have to look for them. Since the introduction of the Internet, there are literally thousands upon thousands of pages of information that are geared specifically toward helping you achieve the pictures of your dreams. You don't have to spend one penny to edit your photographs. All you need is access to a computer and scanner and you are well on your way. Just log onto any one of the number of free photo editor applications available and a whole new world of editing possibilities will be right at your fingertips. Don't let your money, or lack of, keep you from making the best pictures, just download some freeware and start editing your own pictures!
At the opposite end of the spectrum, you can take advantage of the extremely short duration of the flash in low-light situations. Flash firing time can be as short as 1/50,000 of a second, and while the camera's CCD sensor will remain active longer than that, almost all of the light in a dark scene that reaches the CCD will be from that flash event. This can effectively "freeze" the action as if you were using a shutter speed faster than your camera can support. Small built-in flash units have a very short "reach," often providing effective light only as far as two or three meters. This weakness, however, can be turned into a strength if you think about how you want to compose your scene. Certainly for "isolating" or emphasizing your subject, the ability to move only a short distance from background objects and radically reduce their light level is handy. In night shots outdoors or low-level indoor shots, the "weaker" flash gives more control over the content of the shot by dramatically reducing the "foreground" and magnifying the effect of distance.
Secure Digital (SD) cards were designed to replace the older MMC standard - but it's beginning to look like the reverse may happen. The good news is that SD cards are available in larger sized - up to 4 Gigabytes, and higher speeds than MMC cards currently are. In theory, SD cards are the fastest on the market. In practice, it's almost a dead heat with Compact Flash cards. The bad news is that SD cards are losing market share rapidly, though they are still used in many cameras. The better news is that if the MMC standard takes over, full-size MMC cards can be used in SD slots. Compact Flash (CF) is one of the oldest and most popular standards available today. They have the widest range of sizes (up to 8 Gigabytes with larger microdrive-based cards rumored) and are quite quick. Currently they compete only with SD cards for the high-end camera market, and their position looks more secure than SD. New developments in wireless transfer support for cameras and links to external drive packs may cement CF cards' place.
Overcome difficult obstacles while learning digital photography Avoide annoyances with printers, and get aid with this free report.
Most photographs aren't just well-defined black and white boundaries - in fact, none of them are. So when faced with angles, gradients, or irregular shapes, the computer has to use its stored rules to guess what color the new pixels should be. In theory, the better routines allow the computer to do a pretty good job at smoothing out the image when the resolution is increased and all those new pixels are put in place. In practice, unlike in the movies or on TV, you can't get information out of a picture that isn't there. That tiny black dot on the horizon isn't going to turn into an umbrella when you double the resolution, it will just be a bigger black dot. So if you need a "bigger picture" than you have, why not use interpolation? The trick is that the interpolation done in your camera is not the same as the interpolation done in your computer's editing software.
You can recreate the settings of a favorite shot or repeat a favorite effect, and higher-level information such as special lenses and light metering modes can be invaluable as you advance your knowledge of photography. You can even share this information with friends or colleagues to help duplicate tricky shots, or create a database or spreadsheet of the effects of specific settings to help you recreate effects or types of shots under different conditions. An example would be keeping track of how white balance changes affect the appearance of particular colors. Instead of making notes of what changes you made and what order photos were taken in (particularly when the string of photos were all taken of the same scene), you can skip the notes and compare the settings in the EXIF data instead. Then, when you work on your log, you can copy setting information over and just make a note about which settings worked best.
Rough Side of RAW: RAW formats differ from camera to camera and there are debates about camera programming that provides some control over your RAW files by the camera manufacturer. Where protests have been issued, there is an effort to provide standardized RAW formats that would better serve the consumer where general market software could be used to edit the RAW material. If your computer is equipped with lots of processing memory, RAW data will not be as much a problem, however presently, RAW files take a lot more time to open and process than JPEG and TIFF files. That is where the option to capture in RAW and JPEG simultaneously is a strong benefit. While standard editing software is now offered on the market, the way that software processes RAW files may differ depending on how the software from the manufacturer is recognized by the software. Thus, be sure to find and ask a savvy sales expert. Most sensors record light over a 12-bit range, with intensities of more or less 4096 possible values. Each sensor with 12-bit output is one and a half bytes. So our small chip with 20,000 light cells gives a raw output of 30,000 bytes. In an actual file there is some non-image information, but that can be ignored for simple calculations.
Analog or film cameras use the term ASA speed, however it is important to remember that a single digital camera can capture and store images at several ISO speeds. Amplifying the image signal in a camera can also amplify noise and thereby higher ISO speeds may produce progressively more noise in the photo. The character of an image in a photo can also change noise. Where lighter areas in analog or film photos tend to have the most noise, it is the darker areas of digital photographs that have the largest amount of noise. Digital cameras produce three types of noise called random noise, fixed pattern noise and banding noise. Random noise describes the abnormal intensity of color fluctuations compared to the rest of the photograph. It is most influenced by the ISO speed however the pattern of random noise may change even if exposure settings remain the same. Random noise may be the least objectionable, but the most difficult to remove where the noise is too often mistaken for true image characteristics. Fixed Hot pixels or fixed pattern noise describe pixel intensity that far exceeds that of ambient random noise fluctuations.
If you are looking to turn your pictures into pieces of art, there are many options available to you, as well. You can turn your print into a black and white picture and hand color some details. You can create beautiful special effects that will really make your digital photo stand out in a crowd, too. As you can image, the tools to create the perfect picture can cost a lot of money, if you have to purchase them. If you are on a budget, or just like to save money, anything you can find for free is a bonus! Well, there are free photo editors out there, you just have to look for them. Since the introduction of the Internet, there are literally thousands upon thousands of pages of information that are geared specifically toward helping you achieve the pictures of your dreams. You don't have to spend one penny to edit your photographs. All you need is access to a computer and scanner and you are well on your way. Just log onto any one of the number of free photo editor applications available and a whole new world of editing possibilities will be right at your fingertips. Don't let your money, or lack of, keep you from making the best pictures, just download some freeware and start editing your own pictures!
At the opposite end of the spectrum, you can take advantage of the extremely short duration of the flash in low-light situations. Flash firing time can be as short as 1/50,000 of a second, and while the camera's CCD sensor will remain active longer than that, almost all of the light in a dark scene that reaches the CCD will be from that flash event. This can effectively "freeze" the action as if you were using a shutter speed faster than your camera can support. Small built-in flash units have a very short "reach," often providing effective light only as far as two or three meters. This weakness, however, can be turned into a strength if you think about how you want to compose your scene. Certainly for "isolating" or emphasizing your subject, the ability to move only a short distance from background objects and radically reduce their light level is handy. In night shots outdoors or low-level indoor shots, the "weaker" flash gives more control over the content of the shot by dramatically reducing the "foreground" and magnifying the effect of distance.
Secure Digital (SD) cards were designed to replace the older MMC standard - but it's beginning to look like the reverse may happen. The good news is that SD cards are available in larger sized - up to 4 Gigabytes, and higher speeds than MMC cards currently are. In theory, SD cards are the fastest on the market. In practice, it's almost a dead heat with Compact Flash cards. The bad news is that SD cards are losing market share rapidly, though they are still used in many cameras. The better news is that if the MMC standard takes over, full-size MMC cards can be used in SD slots. Compact Flash (CF) is one of the oldest and most popular standards available today. They have the widest range of sizes (up to 8 Gigabytes with larger microdrive-based cards rumored) and are quite quick. Currently they compete only with SD cards for the high-end camera market, and their position looks more secure than SD. New developments in wireless transfer support for cameras and links to external drive packs may cement CF cards' place.
Overcome difficult obstacles while learning digital photography Avoide annoyances with printers, and get aid with this free report.
Comments
Post a Comment