COMM 242, Advanced News Photography (Photojournalism)
Exercise: exposure
Complete with a partner if possible.

Keeping in mind that f/stops, shutter speeds and film speeds generally are related by precisely half or double. That is, changing your f/stop from, say, 4 to 5.6 (one stop) is the same as changing your shutter speed from 125 to 250. Film nowadays, too, is measured in comparable numbers: 50 is half as sensitive as 100; 200 is twice as sensitive as 100, etc. So if you want to change f/stops, shutter speeds or film speeds while maintaining the same exposure, you need to also adjust the other variables.

Standard f/stops: 1.4 (widest opening),1.8 (or 2), 2.8, 4, 5.6, 8, 11, 16, 22, 32, 45.

Standard shutter speeds:1 (one second, slowest shutter speed), 2 (half second), 4, 8, 15, 30, 60, 125, 250, 500, 1000, 2000.

Standard ISO speeds: 25, 50, 100, 200, 400, 800, 1600, 3200.

Try this in the exercises below. Your camera is set to manual mode. Your light meter shows you a combination of f/stop and shutter speed as indicated. Assuming you wish to maintain the same amount of light striking the film for proper exposure, calculate the comparable numbers for each alternative.

1. Indicated f/stop: 5.6. Indicated shutter speed: 125.
You wish to change your f/stop to 4. Your shutter speed will be____?

2, Indicated f/stop: 5.6. Indicated shutter speed: 125.
You wish to change your f/stop to 8. Your shutter speed will be____?

3. Indicated f/stop: 5.6. Indicated shutter speed: 125.
You wish to change your f/stop to 11. Your shutter speed will be____?

4. Indicated f/stop: 16. Indicated shutter speed: 60.
You wish to change your f/stop to 5.6. Your shutter speed will be____?

5. Indicated shutter speed: 30. Indicated f/stop: 5.6.
You wish to change your shutter speed to 60. Your f/stop will be____?

6. Indicated shutter speed: 30. Indicated f/stop: 5.6.
You wish to change your shutter speed to 250. Your f/stop will be____?

7. Indicated shutter speed: 125. Indicated f/stop: 16
You wish to change your shutter speed to 500. Your f/stop will be____?

8. You have a variable focal length (zoom) lens marked 1:4. You know this means the widest the aperture can open is f/4.
Indicated shutter speed: 15. Indicated f/stop: 4. Your ISO number: 100.

You know this is too slow a shutter speed to hand-hold your camera for sharp pictures. While you could lean against a wall or us a tripod, you also could choose a faster ISO speed. The speed you might choose:____.

9. Choosing the ISO number you indicated above, what will be your new f/stop and shutter speed combination?
F/stop_____. Shutter speed_____.

10. You have a zoom lens marked 1:5.6
Indicated shutter speed: 60. Indicated f/stop: 5.6. Your ISO: 200. You wish to change your shutter speed to 500, to stop action at a track meet. What ISO speed would you need to choose? ISO_____.

11. You want to photograph people on the street, and know that you have to work quickly. Focus may be a problem, so you need to set your camera for maximum depth of field. Which setting would be best?

a. Aperture f/4.

b. Aperture f/11.

c. Aperture f/5.6

d. Shutter speed 60.

12. You want to photograph a basketball game, and need to stop fast action. Which setting would work best?

a. Shutter speed 60.

b. Shutter speed 15.

c. Shutter speed 500.

d. Aperture f/16.