BY : DANAYA JEFFERSON & ANTWANISHA GREEN

LENS

<3 LENS FOCAL LENGTH

• Lenses are described in terms of its focal length .

• Focal length controls magnification .

• Focal length also controls angle of view .

<3 NORMAL-FOCAL-LENGTH

• A lens of normal focal length approximates the impression human vision gives .

• A lens of normal focal length has certain advantages over lenses of longer or shorter focal length . They are normally faster, open to to a wider maximum aperture, so shutter speed can be faster or don’t open as wide in dimmer light . They are often less expensive, more compact, and lighter in weight .

<3 LONG-FOCAL-LENGTH

• A lens of long focal length provides greater image magnification and a narrow angle of view .

• Long lenses are excellent when you can or do not want to get close to the object .

• Long lenses have less depth of field so objects in the background can be out of focus .

• Long lenses have some disadvantages . They are usually heavier, bulkier, and more expensive . They have relatively shallow depth of field so they must be focused accurately .

<3 SHORT-FOCAL-LENGTH

• A short lens is more commonly called a wide angle lens .

• A lens of short focal length increases the angle of view and shows more of the scene .

• Short lenses are very useful when you are prevented from moving back as much as necessary .

• Short lenses have considerable depth of field .

• A short lens can distort perspective . Objects close to the lens can appear larger than an object of the same size that is farther away .

<3 ZOOM LENSES• Zoom lenses are popular because they

combine a range of focal lengths into one lens .

• A zoom has disadvantages . They are often more expensive, bulkier, and heavier .

• Zoom lenses are best used when where light is ample because they have small maximum aperture .

<3 SPECIAL-PURPOSE LENSES• Macro lenses1. A macro lens is useful extremely up close

shots .

2. This lens lets you focus at a very close range .

• Fisheye lenses1. A fisheye lens have the widest of wide-angle

views .

2. This lens exaggerates degree differences in size between objects that are near to the camera and those who are farther away .

<3 FOCUSING• Manual focus1. When you use manual focus, you select the part of the scene you want to be

sharpest .

• Follow focus1. This is an technique that lets you keep a subject that is moving toward you

well focused .

• Automatic focus1. This does the focusing for you .

2. If your subject is not in the center, you can use auto focus lock to make it sharp .

• Shutter speed and aperture play an important role in making objects appear sharp in the final picture .