**Contact Mrs [[mailto:Killmore vkillmore@tully.k12.ny.us|Killmoremailto/**vkillmore@tully.k12.ny.us|]]vkillmore@tully.k12.ny.us]] Please put your name in the subject line so I know it is from you.

Histograms
Aperture Controls Light and Depth Of Field

The Shutter Controls time of Light and Motion
Using Shutter Speed and Aperture Together
When taking photos, one of the first decisions you make with many cameras is which exposure mode to use. As you've seen, your choice determines if you control the aperture or shutter speed. If your camera lets you select them, you can pair a fast shutter speed (to let in light for a short time) with a large aperture (to let in bright light) or a slow shutter speed (long time) with a small aperture (dim light).
Speaking of exposure only, it doesn't make any difference which combination you use. But in other ways, it does make a difference, and it is just this difference that gives you some creative opportunities. Whether you know it or not, you're always balancing camera or subject movement against depth of field because a change in one causes a change in the other. Let's see why.
As you've seen, shutter speeds and apertures each have a standard series of settings called "stops".

  • With shutter speeds, each stop is a second or more, or a fraction of second indicating how long the shutter is open.
  • With apertures they are f/stops indicating the size of the opening through which light enters.
The stops are arranged so that a change of 1 stop lets in half or twice the light of the next setting. A shutter speed of 1/60 second lets in half the light that 1/30 second does, and twice the light of 1/125 second. An aperture of f/8 lets in half the light that f/5.6 does, and twice the light of f/11. If you make the shutter speed 1 stop slower (letting in 1 stop more light), and an aperture 1 full stop smaller (letting in 1 stop less light), the exposure doesn't change. (In all modes other than manual this happens automatically). However, you increase the depth of field slightly and also the possibility of blur from camera or subject movement.
  • For fast-moving subjects you need a fast shutter speed (although the focal length of the lens you are using, the closeness of the subject, and the direction in which it's moving also affect how motion is portrayed). When photographing moving subjects shutter-priority mode is favored because it gives you direct control over the shutter speed.
  • For maximum depth of field, with the entire scene sharp from near to far, you need a small aperture (although the focal length of the lens and the distance to the subject also affects depth of field). When photographing landscapes and portraits aperture-priority mode is favored because it gives you direct control over the aperture and depth of field.
Shutter Speed

30 seconds
4 seconds
2 seconds
1/2 second
1/4 second
1/30 second
Read Out

30”
4”
2"
2
4
30
On many cameras a quotation mark (") indicates full seconds and a fraction's denominator without a quotation mark indicates fractional seconds. For example, 2" means 2 seconds and 2 means 1/2 second.
Exposure—Faucets & Buckets Analogy
One way to think of apertures and shutter speeds is to use the analogy of a faucet for the aperture and a timer for the shutter speed.

  • When you open a faucet all the way, water gushes out so you fill a bucket in a very short time. This is the same as pairing a large aperture and fast shutter speed to let in bright light for a short time.
  • When you open a faucet just a little, water trickles out and so it takes a much longer time to fill a bucket. This is the same as pairing a small aperture and slow shutter speed to let in dim light for a longer time.
No matter which combination you choose, the bucket is filled the same amount. Likewise, an image in a camera can be exposed the same amount by various aperture and shutter speed combinations while also controlling motion and depth of field.
Taken from http://www.shortcourses.com/use/using1-10.html


Your assignment this week is to take 5 different shots with different Iso(film speed) and aperture settings for a total of 20 images. That means for every shot you need to change either/and Iso and aperture settings 4 times, and record the information for the changes.This assignment can be difficult for low end cameras but we will try anyways. The aperture setting will be different than on a 35 mm camera. Aperture on lowend cameras looks like this
external image modes.jpg
Speed of film is usually a setting called ISO it nay be different on your camera.
external image fastshutterspeed.jpg



Grading

What to do

Value

1
Create an album called aswf at http://photobucket.com with your initials in the name. ex vkaswf
Create a second link on your personal wiki page. Make sure it is at the top of your personal home page. create a link on this page to your photo bucket (vkaswf). Call it insert your initials) aswf.
15
2
Copy and paste this rubric at the bottom of your aswfvk wiki page, Please use the text editor.
15
4
5 different shots with different Iso(film speed) and aperture settings for a total of 20 images. That means for every shot you need to change either/and Iso and aperture settings 4 times Important requirements
  • Images should be B+W
  • Images posted to your wiki as well as the Photobucket site should be no larger than 1mg
  • Please record the information for the changes.
  • Please use the aswfvk for numbering your shots ex aswfvk1, aswfvk2,aswfvk3
60
6
Complete assignment by Monday March 17 th, 2008.By 12 AM
10
7
Total
100