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.
Exchangeable Image File (EXIF) data, saved by modern digital cameras in each picture file, is a powerful tool for both keeping track of your work and learning more about how to use your camera and how to take advantage of its capabilities. Created by the Japan Electronics and Information Technology Industries Association, this standard is now used by almost all digital cameras. EXIF data stores, as part of the picture file, information such as the date, time, camera model, and settings such as focus mode, flash mode, ISO sensitivity setting, white balance, and many more facts about the state of the camera when the picture was taken. The EXIF data actually envelops the picture data, be it compressed (usually JPEG format) or uncompressed (RAW or TIFF format) data. The data does add anywhere from 100 bytes to 64 kilobytes to the size of the file, but it is invaluable for anything from keeping track of work, indexing large numbers of photographs, or learning more about how your camera’s settings affect the quality of the final product.
If you have ever wondered why TIFF files are historically larger than JPEGs we provide an explanation that will hopefully dispel the mystery. Even though TIFF files retain only 8 bits per channel of data, that data will take up twice the storage space because it has three 8 bit color channels versus the one 12 bit RAW channel. JPEG uses compression of the data at the cost of image quality to manage the data. Thus, RAW data offers the best of both worlds where it preserves the original color bit depth and image quality while saving space using only one 12 bit RAW channel. Some cameras offer compressed RAW that minimally compromises data. If you are taking photographs for fun, JPEG offers an option to increase the number of photos stored on a memory disk. So, why would you want to archive your photographs also as a RAW data file?
Higher temperatures and long exposures may increase the occurrence of hot pixels. Fixed pattern noise is unique where it often shows similar distributions of hot pixels even if taken under the same ISO speed, temperature and length of exposure. Fixed pattern while the most objectionable visually, is the easiest of the three to remove because it is a repeated pattern. Once the internal electronics of a camera knows the pattern, it can subtract the noise away to reveal the true image. Banding noise is associated with the camera model and related characteristics. It is most visible at high ISO speeds and in shadows. When brightening an image, banding noise may become noticeable when using white balances. It is not always the number of pixels that reduces noise, but actually the greater the area of a pixel in a camera which allows a greater amount of light into the pixel causing the sensor to produce a stronger signal. Cameras with physically larger pixels generally appear less noisy since the signal is larger relative to the noise.
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!
For best results using fill flash, try to have your subject in shade with lit areas behind it. The fill flash takes care of the shade, and helps balance the light level so the subject and the background are clear and proportionately bright. If your camera has a “slow synchronized flash” feature, this can be used to combine foreground and background elements in a way not otherwise possible (because of the short reach of small, built-in flashes). With the use of a tripod and relatively still subjects, good quality shots can be taken in otherwise difficult conditions, such as night shots or even shots on a moving platform. Longer shutter delays can produce blur effects similar to the “moving traffic” effects often seen in advertising, and with a little patient experimentation you can produce shots with a mid-range digital camera that rival expensive commercial art.
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.
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