Other Camera Features
The top image hasn't been sharpened, the bottom one has been exaggerated here for effect.
Many digital cameras have a variety of controls that are useful in studio photography.
Sensitivity and Noise Reduction
ISO is a set of standards used to designate film speeds. There is no equivalent standard for digital cameras but the sensitivity of a sensor to light is given as an ISO equivalent. Changing sensitivity can be useful at times. For example, to increase depth of field, you can increase the image sensor's sensitivity (ISO) so less light is needed for a picture and the aperture can be made smaller.
Increasing sensitivity adds some noise to the image and the more you increase sensitivity, the more noise you get. This is because increasing sensitivity amplifies the captured signal, but also amplifies the background noise captured along with it. The noise appears as randomly spaced bright pixels in the image, especially in shadow areas. This noise reduces the image's sharpness and makes it look fuzzy. To reduce noise, many cameras have a noise reduction mode that you can turn on.
The normal default sensitivity (Auto) is equal to about ISO 100. In the studio it's rare that you'll have to increase sensitivity, but some cameras will do it automatically if you leave it set to Auto. To keep the ISO from increasing,take it off auto and set it to the lowest number, usually 100 or so.
Image Manipulation
Many photographer's like to use a photo-editing program to open and tweak the images they take. The things they are most likely to tweak are sharpness, saturation, brightness and contrast. Some cameras allow you to do this at the time you take the picture.
- Most cameras automatically sharpen the edges of details and borders in your images, but some allow you to specify how much sharpening is used, or even turn it off. As you make this adjustment, be aware that you can't see its affects on the camera's screen.
- Saturation controls the intensity of color in an image and some cameras let you increase or decrease it.
- Brightness raises or lowers the brightness of the entire scene to make everything lighter or darker without changing detail in the highlights and shadows.
- Contrast adjusts the differences between the brightest and darkest areas in the image. Increasing contrast increases the differences between the brightest and darkest areas in the image. Decreasing it reduces the differences between the brightest and darkest areas in the image.
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