Sensitivity to light of image sensor
measured according to ISO system. When it’s dark the higher sensitivity to
light is needed, so high ISO numbers are preferred. NB! The higher ISO number is
the grainy image will be.
Diaphragm is a structure which controls the
amount of light passing through the lens. In photography it refers to aperture
or f-number. Typical ranges of apertures are f/2.8 – f/22, respectively from
the maximum to minimum aperture. The smaller apertures (the bigger f-number)
are used for the luminous objects or to increase the depth of field.
Exposure Value (EV). In cameras it refers
to exposure compensation stated in terms of +EV or –EV. For example, +EV means
to increase the exposure by using either a smaller shutter speed or a smaller
f-number. +EV is used for the dark
objects whereas –EV for the luminous ones.
Normal lens is a lens with the focal length
almost equal to the diagonal size of the image sensor; the perspective looks
like natural.
Wide-angle lens is a lens with the shorter
focal length; it is used for the panoramic pictures.
Telephoto lens is a lens
with the longer focal length; it’s better to use them for portraits or in macro
photography.
No comments:
Post a Comment