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• Standard/normal lens - a focal length that is roughly equivalent to the diagonal of the light-sensite area within the camera
• Long focus lens - a focal length that is much greater than diagonal of the film or image format with which it is used
• Mirror lens - a combination of glass elements and mirror that bounds the light and down the lens barrel
• Wide angle lens - a focal length shorter than diagonal of the film frame or image senior
• Zoom lens - it allow fine tuning of subject framing by adjusting the vocal length of the lens
• Ultra-wide angle lens - a focal length ranging from around 21 mm down to around 15 mm
• Wide Angle zoom - it has the advantage of being able to select intermediate focal length settings
• Shift lens - it can be shifted off center in relation to the film frame
• Macro lens - they are useful in taking close-ups of small objects
• Astigmatism - the inability of the lens the lens to focus in both horizontal and vertical plane at the same time