Objective: Students will understand how aperture affects depth of field and will use Av exposure mode to create different depths of field in a series of photographs.
Think of it like your pupil. When its dark out, your pupils open very wide to let more light in to help you see better. When you are outside in the bright sun, your pupils get smaller, to block some of that light out!
The size of the aperture is referred to as an "f-stop." Larger f-stop numbers (like f/22) designate a smaller aperture. Smaller f-stop numbers (like f/2.8) designate a wider aperture. (Confusing, I know!)
Shutter speed also controls your "depth of field" or the area of your photo that is in focus. A small aperture (larger f-stop number) will keep most if not all of your image in clear focus. A wide aperture (smaller f-stop number) will keep only a certain area of your photo in focus, leaving elements outside of that area blurry.
Your f-stop controls:
- Exposure (how much light is let in to your camera)
- Depth of Field (the area of your photo that is in focus)
What is depth of field?
3 ways to affect depth of field:
to create shallow depth of field:
- LARGE APERTURE (small f-stop number
- LONGER FOCAL LENGTH (zoom-in)
- CAMERA CLOSER TO SUBJECT, SUBJECT FARTHER FROM BACKGROUND
TO CREATE LARGE DEPTH OF FIELD:
- SMALL APERTURE (large f-stop number)
- SHORTER FOCAL LENGTH (zoom-out)
- CAMERA FARTHER AWAY FROM SUBJECT, SUBJECT CLOSER TO BACKGROUND
what exposure mode should i use?
While you are in Av Mode, you can rotate your main dial (next to the shutter button) to quickly adjust your f-stop. You will see your f-stop value on the bottom of your viewfinder.
Remember, the lower the f-stop number (2.8) the LARGER your aperture and the SHALLOWER your depth of field.
The higher your f-stop number (22) the SMALLER your aperture and the WIDER your depth of field.
Depth of Field Assignment 1:
You will take 3 photographs of your subjects. Use a tripod and do not move your camera in between shots.
- SHOT 1: Use a small aperture (large f-stop #) to create a large depth of field. BOTH of your subjects should be in focus.
- SHOT 2: Use a large aperture (small f-stop #) to create a shallow depth of field. Use manual focus so that ONLY the subject in the FOREGROUND is in focus. The background subject should be blurry.
- SHOT 3: Use a large aperture (small f-stop #) to create a shallow depth of field. Use manual focus so that ONLY the subject in the BACKGROUND is in focus. The foreground subject should be blurry.
depth of field assignment 2:
See Schoology.com for submission instructions.
LARGE DEPTH OF FIELD
Useful when you want everything (near and far) to be in sharp focus, such as with a landscape.
SHALLOW DEPTH OF FIELD
Useful when you only want a certain part of the image in focus, and the rest blurred out.
This is useful in portraits. By blurring out the background, you simplify the image and keep the focus on your subject.
It’s time to open up those apertures and whip out your photos that best demonstrate the beauty of a shallow depth of field! We’ve been studying exposure—aperture, shutter speed, etc.—for the past several days (read previous posts to brush up if you need to), so let’s all share our shallow depth-of-field photos! It’ll keep us honest.
To enter, just submit your favorite shallow depth-of-field photos to the Pioneer Woman Photography Assignments group on Flickr. I will review each and every submission and, beginning Tuesday morning, will post daily groups of those photos that especially stand out. Here’s the schedule:
Tuesday: Group 1
Wednesday: Group 2
Thursday: Group 3
Friday: Group 4
Saturday: Finalists from each group will be posted
Monday: Winners (and prizes) announced!
Prizes for this assignment will be great fun, but the best part about these assignments is the opportunity to gaze upon the unbridled talent of so many of you out there. The previous assignments have just been amazing.
* One photo submission per day (the system will only permit one, just to make it easy!)
* Submit your favorite photos that demonstrate shallow depth-of-field
* Finalists will be selected based on creativity, clarity, color, and how well it falls under the assignment category
* Most importantly: enjoy looking at everyone’s submissions!
Can’t wait to see your stuff!