1. TTF
01-Exposure & Stops

2. Camera Camera light Aperture sensitive Shutter & material Lens
Total Exposure depends on
1. Aperture area f/#
2. Time the shutter is open t
3. Sensitivity of the "film" ISO Sensitivity
Camera
Camera
light
Aperture
sensitive
Shutter
&
material
Lens
ISO:
Brighter Image
Darker Image
A factor of 2 is called a "Stop"

3. Exposure time, t, is controlled
by the amount of time the
camera detector is turned "ON". t
t: 1/ / /250 1/125 1/60 1/30 1/15 1/8 1/4 1/2 1 seconds
t: 1/ / /256 1/128 1/64 1/32 1/16 1/8 1/4 1/2 1 seconds
Darker
Brighter

4. Aperture stop and f/# f = focal length of lens d
Less Exposure (large F/#)
More Exposure (small F/#)

5. f/#
indicator
adjustment
ring

6. Exposure is spaced by a factor of 2, or a "Stop".32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
Darker
Lighter

7. Find a combination that makes a good exposure.
This is the "Balanced Condition"
f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
Darker
Lighter

8. If we change ONLY ONE of these three…….32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
Darker
Lighter

9. ……we are no longer in "Balance".
1600
800
400
200
100
ISO 1
1/2
1/4
1/8
1/15
1/30
1/60
1/125
1/250
1/500
1/1000 t
1.4 2
2.8 4
5.6 8 11 16 22 32
f/#
Darker
Lighter
Example of an "Over Exposure"

10. Shift the other two factors to return to balance.
1600
800
400
200
100
ISO 1
1/2
1/4
1/8
1/15
1/30
1/60
1/125
1/250
1/500
1/1000 t
1.4 2
2.8 4
5.6 8 11 16 22 32
f/#
Darker
Lighter
Example of an "Over Exposure"

11. Back to a "Balanced" Exposure
f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
Darker
Lighter
Back to a "Balanced" Exposure

12. More Examples Darker Lighter f/# 32 22 16 11 8 5.6 4 2.8 2 1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
Darker
Lighter
f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600

13. Keep in Balance with equal shifts both ways32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
Darker
Lighter
f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600

14. f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
???
Darker
Lighter
f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
???

15. f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
Darker
Lighter
f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600

16. f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
???
Darker
Lighter
f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
???

17. f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
Darker
Lighter
f/# 32 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600

18. Photo-Effects of
Shutter Speed
F/#
and
Focal Length

19. F/#: 4 Shutter Speed: 1/60 Sec ISO: 200 F/#: 1132 22 16 11 8
5.6 4
2.8 2
1.4 1 t
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
F/#: 4
Shutter Speed: 1/60 Sec
ISO: 200
F/#: 11
Shutter Speed: .1/8 Sec
ISO: 200

20. t=1/8 sec f/#=32 t=1/250 sec f/#=5.6 f/# 32 22 16 11 8 5.6 4 2.8 2 1.4
1/1000
1/500
1/250
1/125
1/60
1/30
1/15
1/8
1/4
1/2
ISO
100
200
400
800
1600
t=1/8 sec f/#=32
t=1/250 sec f/#=5.6

21. 1/100 at f/22, Short focal length ("Zoomed Out")

22. 1/100 at f/22, Long focal length ("Zoomed In")

23. Exposure Modulation

24. Long Exposure time in the dark: Write with a light source.

25. Double Exposure:
Turn room lights on, off, on, off

26. How was this done?

27. End