Relatively insensitive film, with a correspondingly lower speed index requires more exposure to light to produce the same image density as a more sensitive film, and is thus commonly termed a slow film. Highly sensitive films are correspondingly termed fast films. In both digital and film photography, the reduction of exposure corresponding to use of higher sensitivities generally leads to reduced image quality (via coarser film grain or higher image noise of other types). In short, the higher the sensitivity, the grainier the image will be.
Photography TerminologyTechnology and Media Productions
Pixel• A picture element• (pix=picture and el-element)• In color image systems, a color is typically represented by three or four component intensities such as red, green, and blue, or cyan, magenta, yellow, and black.
File size• Image file size is positively correlated to the number of pixels in an image and the color depth, or bits per pixel
Types of Files• JPEG (Joint Photographic Experts Group) is a compression method. Nearly every digital camera can save images in the JPEG/JFIF format, which supports 8-bit grayscale images and 24-bit color images (8 bits each for red, green, and blue).• The TIFF (Tagged Image File Format) format is a flexible format that normally saves 8 bits or 16 bits per color (red, green, blue) for 24-bit and 48-bit totals, respectively, usually using either the TIFF or TIF filename extension.• GIF (Graphics Interchange Format) is limited to an 8-bit palette, or 256 colors.• The BMP file format (Windows bitmap) handles graphics files within the Microsoft Windows OS. Typically, BMP files are uncompressed, hence they are large; the advantage is their simplicity and wide acceptance in Windows programs.• The PNG (Portable Network Graphics) file format was created as the free, open-source successor to GIF. The PNG file format supports 8 bit paletted images (with optional transparency for all palette colors) and 24 bit truecolor (16 million colors) or 48 bit truecolor with and without alpha channel - while GIF supports only 256 colors and a single transparent color.
Exposure• The quantity of light allowed to act on a photographic material; a product of the intensity (controlled by the lens opening) and the duration (controlled by the shutter speed or enlarging time) of light striking the film or paper. [Brightness/Darkness of the final photo]
Shutter Speed• shutter speed or exposure time is the effective length of time a cameras shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor.
Aperture• an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane
ISO (film speed)• Film speed is the measure of a photographic films sensitivity to light, determined by sensitometry and measured on various numerical scales, the most recent being the ISO system. A closely related ISO system is used to measure the sensitivity of digital imaging systems.
White Balance• Color Temperature of the image. Setting depend on the lighting available.
Angle of View• The area of a scene that a lens covers or sees. Angle of view is determined by the focal length of the lens. A wide-angle lens (short- focal-length) includes more of the scene-a wider angle of view- than a normal (normal- focal-length) or telephoto (long-focal- length) lens. [What the lens sees, kind of like what you see when you look at something]