Despite what you thought about math in school, it does have
applications in the real world. Photographers, for instance, use math to
calculate a number of settings for their cameras, including shutter speed,
aperture and focal length. Math is also applied to the composition of a
photograph using the rule of thirds.
Step 1
Change the shutter speed to adjust how much light is allowed into the camera
for a certain length of time. The camera's shutter speeds are calculated in
fractions of seconds, which are usually 1/1000, 1/500, 1/250, 1/60, 1/30, 1/15,
1/8, 1/4, 1/2 and 1. Calculating the correct shutter speed to use is a matter
of understanding geometric sequence. As you increase the speed from 1/1000
toward 1 second, each increase multiplies the amount of light entering the lens
by a factor of 2.
Step 2
Determine the aperture to adjust the diameter of the camera lens. The larger
it is, the more light is taken in by the lens. Aperture is measured by the
diameter of the lens or mirror, while its ability to gather light is affected
by its area. Understanding how to adjust the aperture of the camera telescope
requires an understanding of the area of a circle, which equals pi times its
radius squared.
Step 3
Calculate the relationship between the aperture and the focal length. A lens
with a 28 millimeter focal length and an aperture of 14 millimeters
photographing a 20 meter by 30 meter wall has an area four times greater than a
55 millimeter lens with the same aperture. Find the area of both shots by using
the measurements of the wall, which equals 600 meters squared. The 55
millimeter lens has twice the focal length of the 28 millimeter lens and an
area of 150 meters squared. The 28 millimeter lens has an area four times
greater than the 55 millimeter lens, meaning the latter lens sees only a fourth
of the scene and a fourth of the light that the 28 millimeter lens sees.
Step 4
Determine the amount of stops between two f-stop numbers. F-stops refer to
the relationship between focal length and aperture diameter. The camera lens is
typically marked with f-stops that manipulate the aperture from large to small
to adjust the sharpness in depth of field. A common way to remember f-stops is
to multiply the previous number by its constant value. For instance, a camera
with common f-stops of 1, 1.4, 2, 2.8, 4, 5.6, 11, 16, 22, 32, 45, 64, 90, 128
has a constant value of 2. That means if you multiple any number in the
sequence by 2 you will get the number after the next in the sequence. Setting
the f-stop is essentially setting the lens aperture diameter. Therefore, the
diameter of the lens aperture is measured by the focal length of your lens
divided by the f-stop number. For instance, a lens with a 50 millimeter focal
length and an f-stop number of 2 will have an aperture diameter of 25
millimeters.
Step 5
Use the rule of thirds to frame a photograph that pleases the eye. The rule
of thirds addresses breaking down an image into nine equal fractions on a
horizontal and vertical path and lining up important elements of the photo with
the lines. The rule of thirds can give subjects a sense of direction and help
balance the visual weight of objects in the photo.
After all said, what do you need to put all these to practical is a DSLR camera.
DSLR camera- This is a Digital Single Lens Reflex camera (also called a digital SLR) that combines the optics and the mechanism of a single-lens reflex camera with a digital imaging sensor as opposed a photographic film.
We will look deeper into the difference between a DSLR Camera and a point and shoot camera.
So the next time you see a photographer working, he/she is also a mathematician.
Are you
