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Flashcards in ISO/ASA/Film Speed Deck (18):
1

ISO/ASA/Film Speed

How sensitive the film or the sensor is to light. As the ISO increases the amount of light that is needed will decrease. As the ISO decreases the amount of light needed will increase.

2

What are the 9 ISO ratings?

50
100
200
400
800
1600
3200
6400
12,800

3

How does the amount of silver effect the ISO rating

Less silver (e.g ISO=50) the less sensitive to light and the longer time to respond to light.
More silver (e.g ISO=3200) The more sensitive to light and the less time it takes to respond to light.

4

What happens when the ISO rating increases?

The sensitivity increases 2X and the light requirement gets cut in half 1/2

5

What happens when you decrease the ISO rating?

When you decrease the ISO you decrease the sensitivity to light which means the light requirement gets cut in half 1/2 and the amount of light needed is 2X as much.

6

Grain

Noise
There is less silver will create less grain
more silver will create more grain

7

TTL

Through the lens meters: Reads reflective light

8

What are two mechanisms that allow light into the camera?

1. Shutter
2.Aperture

9

What are the 13 Whole stop numbers for Shutter Speed?

B
1
1/2
1/4
1/8
1/15
1/30
1/60
1/125
1/250
1/500
1/1000
1/2000

*Except for 1/8 and 1/60 it doubles per stop

10

What happens when you're "Closing Down" or "Stop Down" in shutter speed?

As you increase the shutter speed the amount of light that enters decreases by 1/2.
You also count the stops that you increase. For example if you increase the shutter speed from 1/2 to 1/4 the amount of light is decreased by 1/2 and the stops are 2 stops. If the shutter speed again is increased to 1/8 the amount of light is decreased to 1/4 the amount needed and you've made 3 stops.

11

What happens when you're "Opening up" in shutter speed?

As the shutter speed decreases the amount of light that is let in, increases by 2X per stop.
For example if the shutter speed decreases from 1/2000 to 1/1000 then the amount of light gets increased 2X. If again you decrease to 1/500 then the shutter speed gets decreased 4X. which is a total of 3 stops.

12

Aperture

Located in the lens. Its the adjustable diaphragm that controls the intensity(amount) of light entering the camera.
The larger the F# the larger the physical diameter of lens
The Smaller the F# the smaller the physical diameter lens
*sensors of lens set aperture
*Digital lens cannot be set manually.

13

The Maximum aperture is known as what?

The speed of the Lens: Also a good description for the quality of the lens.

14

What are the 9 F#'s?

f/2-------->Larger
f/2.8
f/4
f/5.6
f/8
f/11
f/16
f/22
f/32--------->Smaller

15

What happens when the aperture increases?

The amount of light gets cut in half 1/2. For example, if you increase the aperture from f/2 to f/2.8 the amount of light gets cut by 1/2 which is 1 stop. If the aperture increases again to f/4 the light gets cut 1/4. f/8-the light would be cut by 1/16 this would be a total of 4 stops

16

What happens when the aperture decreases?

The amount of light get doubled 2X, For example, if you decrease the aperture from f/22 to f/16 the amount of light is doubled 2X and that is 1 stop. f/22 to f/5.6 would get doubled 16X which is 4 stops.

17

How do aperture and shutter work together?
And what is the term used for this?

When compensating for the shutter to show motion you let in more light through the aperture and visa versa.
The aperture will move the same amount of stops as the shutter speed
1/60--->1/1000 = 4 STOPS
f/8----->f/2.8 =4 STOPS

1/2 1/4 1/8 1/15 1/30 1/60 1/125 1/250 1/500 1/1000
f/22 f/16 f/11 f/8 f/5.6 f/4 f/2.8 f/2

*8 total possibilities depending on the aperture.

This is known as equivalent exposures.

18

Equivalent exposures

When each setting and adjustments made for ISO, shutter, and aperture all let in the same amount of light.
When more light is needed, but the aperture is no longer available then the ISO rating can also be adjusted.

Ex: 50 100 150 200 400 800 1600
1/2 1/4 1/8 1/15 1/30 1/60 1/125 1/250 1/500 1/1000
f/22 f/16 f/11 f/8 f/5.6 f/4 f/2.8 f/2

*when you move the ISO, the number of stops made also determines the number of stops needed to move the aperture setting as well...

Ex: 400 800 1600----->4 STOPS
1/2 1/4 1/8 1/15 1/30 1/60 1/125 1/250 1/500 1/1000
f/4 f/2.8 f/2--------->4 STOPS