Section A · Photography · 11 marks

Exposure.

The exam opens with the camera. Today we lock down the exposure triangle — aperture, shutter speed, ISO — and the scenarios the exam loves to test.

Grab your Exposure active-notes handout
Do Now · 5 minutes
Do Now
  1. Without looking: name the three parts of the exposure triangle.
  2. Your photo of a friend running is a blurry streak. Which setting do you change — and which way?
  3. An indoor photo is too dark. Name one setting you could change to brighten it.

Write your answers in the Do Now box. We’ll check them on the next slide.

Do Now · check
  1. Aperture · Shutter speed · ISO
  2. Faster shutter speed → freezes the motion
  3. Raise ISO (or open the aperture / slow the shutter)
Exam radar

These three are Question 1 almost every year. Easy marks — if you can name them and match each to what it controls.

What Section A tests

11 marks. All exposure.

Name & match

List the three components and match each to what it controls.

Fix the photo

Blurry, dark, grainy, wrong focus — identify which setting to change.

Trade-offs

Push one setting, describe the cost on another (noise, depth, light).

Short answers. Match your effort to the marks — a 1-mark question wants one word; a 2-mark question wants the effect described.

The big idea

The Exposure Triangle

Three settings control how much light reaches the sensor. Change one and you have to compensate with another. That balance is the triangle.

APERTURE — how wide the lens opens SHUTTER SPEED — how long light enters ISO — how sensitive the sensor is
Fill the triangle diagram on your handout
Component 1

Aperture — the hole in the lens

  • How wide the lens opens, measured in f-stops.
  • ⚠ Counter-intuitive: small number = big hole. f/1.8 is wide; f/16 is narrow.
  • Wide (f/1.8) = lots of light + shallow depth of field (blurry background, “bokeh”).
  • Narrow (f/16) = less light + deep depth of field (front-to-back sharp).
Depth of field

Shallow → portraits, blurred background. f/1.8–f/3.5.

Deep → landscapes, everything sharp. f/8–f/16.

f/1.8f/2.8f/5.6f/11f/22
Component 2

Shutter Speed — the curtain

  • How long the shutter stays open, in fractions of a second.
  • Fast (1/500+) freezes motion — sport, a running friend.
  • Slow (1/30 or slower) creates motion blur and lets in more light.
  • Handheld minimum ≈ 1/60. Slower than that, camera shake blurs the shot.
Freeze vs blur

Freeze a fast subject → 1/500–1/2000.

Blur on purpose (light trails, panning) → 1/30 or slower.

1″1/301/601/1251/5001/2000
Component 3

ISO — sensitivity to light

  • How sensitive the sensor is to light.
  • Low (100) = clean image, but needs lots of light.
  • High (1600–3200+) = shoot in the dark, but adds noise / grain.
  • Rule of thumb: keep ISO as low as you can — raise it only when you can’t get light any other way.
The cost

Photo looks grainy / noisy? ISO is pushed too high. That grain is the trade-off for the brightness.

100 clean400 outdoors800 indoors3200 night · grainy
Why it’s a “triangle”

Change one. Compensate with another.

Worked scenario

Freeze a skateboarder indoors? You need a fast shutter — but that cuts the light. So you open the aperture (wider) and / or push the ISO up to keep the photo bright enough.

The exam’s favourite scenarios

Diagnose & fix

  • Subject blurry from movement → shutter speed, faster
  • Photo too dark indoors → ISO up (or open aperture)
  • Background blurred on purpose → aperture, wide (low f-stop)
  • Everything front-to-back sharp → aperture, narrow (high f-stop)
  • Photo grainy / noisy → ISO too high
  • Camera-shake blur, subject still → shutter slower than 1/60 handheld
These six go in your handout’s “diagnose & fix” box
Exam technique

Read the command word

List / State

One word or phrase. No explanation needed.

Identify

Name the right thing for the scenario.

Describe

Name it and say the effect — how / why it happens in the image.

Describe = 2 marks. 1 mark for naming the effect (e.g. “noise”), 1 mark for describing how it shows up in the image.

What a full-mark answer looks like

Worked example

Question · 2 marks

“A photo taken in a dark classroom is too dim. The student raises the ISO. Describe ONE negative effect of pushing ISO too high.”

Model answer · 2/2

Pushing the ISO too high adds digital noise (grain) to the image. The picture looks speckled and less sharp, because the sensor is amplifying the signal — and the detail — as it tries to brighten the shot.

Your turn · interactive

Lock it in

On media.codes/strikes-back

Open the study site and run these in order:

→ Photography · Exposure-triangle drill
→ Notes & Flashcards · Photography set

photography.html  ·  notes.html

Then try the speed round: exposure-lock
Exit ticket

Before you go…

  1. What shutter speed would you use to freeze a runner — and why?
  2. What happens to depth of field as you go from f/2 to f/16?
  3. An indoor photo is too dark. Name two settings you could change.

Confident on all three? Section A is in the bag. Up next: Manipulated — codes, ACA & COCA.