LENSES The specs: focal length maximum aperture “long lenses, short lenses fast lenses, slow...

LENSES

The specs:focal lengthmaximum aperture

“long lenses, short lensesfast lenses, slow lenses”

Fixed focal length (prime)or zoom

FOCAL LENGTH – angle of view and magnification

28 mm 50 mm

70 mm 210 mm

PERSPECTIVE can change with focal lengthbecause it’s a function of viewing location.

Short focal length exaggerates depth.

Long focal length compresses depth.

NORMAL FOCAL LENGTH

50 mm

But…Most digital cameras have a crop factor of 1.5 or more. The sensor is smaller than the traditional 24 X 36 mm film from of 35mm Cameras, so part of the picture is cropped out.Usually about 75% of the view is all you get.So…35mm is ~50 (normal)

50 mm is like 75100mm is like 150200mm is like 300, etc.

WIDE-ANGLE LENSES

Wider field of viewGreater depth of fieldDeep focusMinimize camera shakeEmphasize foregroundGreat for landscapes

Pitfalls:Skewed linesWeird proportionsDistortion at edgesVignettingPoor flash coverage

ULTRA WIDE LENSES – fish-eye6 – 16 mm

TELEPHOTO LENSES

Anything longer than “normal” – 2X, 3X, etc.Short/longNarrow field of view, magnificationIsolation of subject (shallow depth of field)Compression of distance between objectsMagnification of camera shakeSlow shutter speed often requiredHazeFlare

MACRO LENSESClose focusing1:1 reproduction on 35 mm filmFocal length determines working distance

Camera shake magnifiedDepth of field shallowSlow shutter speeds Tripod often necessary

ZOOM VS. PRIME (FIXED FOCAL LENGTH)

Wide angle zoom 12-24 mmMid-range zoom 18-70 mmShort telephoto zoom 70-200 mmLong telephoto zoom 200-500 mmMacro zoom close focusing

Prime lenses are often sharper….but….How many lenses do you want to carry?

Have you tried the zoom during exposure trick?

SPECIALTY LENSES

Perspective controlOptical image stabilizationVibration reductionMacro with ultra small apertureFocus control portraitUV lensesMirror/reflex lenses

BOKEH…good bokeh and bad bokeh

LENS ACCESSORIES

Lens cap!Lens hoodFiltersCleaning supplies – cloth, brush, blowerDioptersExtension tubes, bellowsTeleconverter