ISO: The Final Corner of the Exposure Triangle

ISO

What is a digital photograph?

●A digital pictures is made up of

pixels.

●Pixel is short for “picture element.”
●A BITMAP image is made up of

pixels, and is the most common
form of a digital photograph.

●If you zoom in on a BITMAP image

you will see the individual squares
start to form.

Image Resolution:

● Resolution: In digital imaging, the

number of pixels, in both height and
width, that make up an image.

● The more pixels you have, the greater

the resolution is.

● This means you have to zoom in

farther, in order to see the pixels,
which means you can print the image
larger without it looking pixelated.

● High resolution (Hi-Res)=Good

quality

● Low resolution (Low-Res)=Poor

quality

DPI vs. PPI

●3 factors determine an image’s

resolution:
○ Height
○ Width
○ DPI/PPI

●DPI: Dots per inch
●PPI: Pixels per inch
●DPI refers to how the printer creates

the image-output.

●PPI refers to how the image is created

on the computer screen-input.

PPI

DPI

Match

Match the following definitions

• DPI

• PPI

• Resolution

• Pixel

• BITMAP

How the printer creates an impage

How the comptuer creates an imapge-output

The number of pixels per height and width

Picture Element

It is an image made up of pixels

• How the printer creates an impage

• How the comptuer creates an imapge-output

• The number of pixels per height and width

• Picture Element

• It is an image made up of pixels

Drag and Drop

DPI stands for ​ ​

Placeholder

and refers to how a ​

Placeholder

​ creates an image. PPI stands for

Placeholder

and refers to how the image is created on a ​

Placeholder

.

Drag these tiles and drop them in the correct blank above

Dots Per Inch

printer

Pixels Per Inch

computer screen

Dabs Per Inch

Parts Per Inch

Points Per Inch

canvas

Deltas Per Inch

Picas Per Inch

Dropdown

You can zoom in more with a ​

Select answer

resolution image than a ​

Select answer

resolution. You can also make the image ​

Select answer

without it becoming ​

Select answer

Drag and Drop

The ​ higher the ISO value, the ​

Placeholder

light you'll need in your environment to take a properly exposed photo.

Drag these tiles and drop them in the correct blank above

less

more

Drag and Drop

The ​ lower the ISO value, the ​

Placeholder

light you'll need in your environment to take a properly exposed photo.

Drag these tiles and drop them in the correct blank above

more

less

Drag and Drop

The ​

Placeholder

the ISO value, the​

Placeholder

noise you add to the photo.

Drag these tiles and drop them in the correct blank above

lower

more

less

Multiple Choice

True or false: You want to keep your ISO values as low as possible to reduce noise

• True

• False

Multiple Choice

True or false: You should increase your ISO in low light to better expose your images (after your first adjusted aperture and shutterspeed of course)

• True

• False

Multiple Choice

According to the scenario in the video, he described photographing a kids birthday party in low light. The kids are all moving around. He recommended to do the following

• Increasing the ISO to allow for a slower shutter speed

• Increasing the ISO to allow for a faster shutter speed

• Decreasing the ISO to allow for a slower shutter speed

• Decreasing the ISO to allow for a faster shutter speed

• Cut your losses. This is impossible. Just gab some cake and get out of there!

Match

Match each ISO with the proper lighting condition

• 100

• 200

• 400

• 800

• 1600

Bright Outdoor lighting

Dim Outdoor Lighting

Bright Indoor lighting

Dim Indoor Lighting

Dark Indoor Lighting

• Bright Outdoor lighting

• Dim Outdoor Lighting

• Bright Indoor lighting

• Dim Indoor Lighting

• Dark Indoor Lighting

ISO

●ISO can change how light or dark a photograph is.
●This can give you the power to adjust the look of a

photograph taken in the bright sun, on a cloudy day,
or at night.

●However, the risk with adjusting the ISO is it can add

“noise” to your photograph.

●Noise gives a grainy, pixelated look to an image.
●The higher the ISO, the more noise an image will

have.

Click HERE to go to the camera simulator

1. ​Set the camera to Manual

2. Set your Shutter Speed to 1/60th of second, and your Aperture to F/8

3. Play around with ISO settings to answer the questions

​

​Some text here about the topic of discussion.

ISO Camera Simulator

Multiple Choice

Increase your ISO to 100. What happened?

• The picture became very underexposed

• The picture became slightly underexposed

• The picture became slightly overexposed

• The image became very overexposed

Multiple Choice

Increase your ISO to 400. What happened?

• The picture became very underexposed

• The picture became slightly underexposed

• The picture became slightly overexposed

• The image became very overexposed

Multiple Select

Why did this happen?

• The higher ISO made the camera MORE sensitive to light

• The higher ISO made the camera LESS sensitive to light

• There was too much light in this context for this ISO setting

• There was not enough light in this context for this ISO setting

Multiple Select

Change your simulator to Shutter Speed Priority. As you increase the ISO, what happens to the Aperture

• The aperture gets bigger

• The aperture gets smaller

• The f-stop increases in number

• The f-stop decreases in number

• The depth of feild gets deeper or wider

Multiple Choice

Why does this happen?

• The aperture gets BIGGER because it's trying to allow in MORE light to compensate for the ISO setting

• The aperture gets BIGGER because it's trying to allow in LESS light to compensate for the ISO setting

• The aperture gets SMALLER because it's trying to allow in MORE light to compensate for the ISO setting

• The aperture gets SMALLER because it's trying to allow in LESS light to compensate for the ISO setting

Multiple Select

Change your simulator to Aperture Priority. As you increase the ISO, what happens to the Shutter Speed?

• The shutter speed gets slower

• The shutter speed gets faster

• The shutter speed is more likely to create motion blur

• The shutter speed is more likely to freeze the subject

Multiple Choice

Why does this happen?

• The shutter speed gets FASTER because it's trying to allow in MORE light to compensate for the ISO setting

• The shutter speed gets FASTER because it's trying to allow in LESS light to compensate for the ISO setting

• The shutter speed gets SLOWER because it's trying to allow in MORE light to compensate for the ISO setting

• The shutter speed gets SLOWER because it's trying to allow in LESS light to compensate for the ISO setting

Comparing the ISO:

Just right: ISO 400

Overexposed: ISO 800

Overexposed: ISO 1600

Underexposed: ISO 400

Just right: ISO 800

Overexposed ISO 1600

Multiple Select

In the previous slide, why was the picture of the field considered "just right" at an ISO of 400, but the dining room was best exposed at 800?

• The dining room had brighter lighting

• The dining room had dimmer lighting

• The Field had more natural light

• The Field had less natural light

Photographing an image in a dark room

Multiple Choice

Take a look at the picture on the previous slide. Notice that the photographer is photographing their subject in a dark room. To get the properly exposed image, we can assume that they're using which ISO setting?

• 100

• 200

• 400

• 800

• 1600 or higher

Photographing on a sunny day

Multiple Select

Take a look at the picture on the previous slide. Notice that the photographer is photographing their subject on a cloudy day. To get the properly exposed image, we can assume that they're using which ISO setting?

• 100

• 200

• 400

• 800

• 1600 or higher

Photographing on partly cloudy Day

Multiple Select

Take a look at the picture on the previous slide. Notice that the photographer is photographing their subject on a cloudy day. To get the properly exposed image, we can assume that they're using which ISO setting?

• 100

• 200

• 400

• 800

• 1600 or higher

Multiple Choice

Scenario: You are at an indoor race track taking photos of runners as they compete. You want a shallow of field to really bring focus to the individual athletes. To freeze the action you need at least 1/250ths of a second. Any slower and you'll get motion blur.

You take your picture and it's too dark.

What should you do first?

• Use a higher f-stop

• Use a lower f-stop

• Use a higher ISO

• Use a lower ISO

• Slow your shutter speed below 1/250

Multiple Choice

Scenario: You are still at the race track, and have your aperture set as low as possible. The depth of field is perfect and you're avoiding motion blur. However, your pictures are still too dark.

What should you do now?

• Use a higher f-stop

• Use a lower f-stop

• Use a higher ISO

• Use a lower ISO

• Slow your shutter speed below 1/250

Multiple Choice

Scenario: You are still photographing the newlyweds. You brought your ISO down to 100 (feeling silly because you should have remembered Ms. Lalonde telling you to use an ISO of 100 when taking photos outside in bright light). However, your photos are still overexposed.

What should you do now?

• Use a higher f-stop

• Use a lower f-stop

• Use a higher ISO

• Use a lower ISO

• Use a faster shutter speed

Multiple Choice

Scenario: You are taking a portrait of newlyweds outside and the sun is shining. You are using an ISO of 600, a shutter speed of 1/250th of a second, and an f-stop of 2.8. You want to keep a shallow depth of field to keep the focus on the couple.

What should you do first?

• Use a higher f-stop

• Use a lower f-stop

• Use a higher ISO

• Use a lower ISO

• Use a faster shutter speed

Multiple Select

Scenario: You take your photo, and SUCCESS! It didn't really matter how fast your shutter speed was in this context, as long as you didn't go below 1/60th of a second without a tripod and get camera shake.

You're ready for your next location: inside a quaint little barn with good lighting (this is a rustic farm wedding BTW)

What should you do now?

• Start with an ISO of between 1600-3200

• Sneak off and try to find some cake

• Start with an ISO of between 400-600

• Adjust your ISO higher or lower as needed

• Remember to adjust aperture & shutter speed as well

Multiple Choice

Why is this picture so grainy/noisy?

• High ISO

• Low ISO

Task 2: Aperture Practice

Multiple Choice

Why ISN'T this picture grainy/noisy?

• High ISO

• Low ISO

Multiple Choice

What ISO would you use and why?

• Low ISO, because it's nighttime.

• High ISO, because it's nighttime.

Multiple Choice

This photo used a slow shutter speed to create the light streaks. What ISO would you use and why?

• It's night, so I'd usually use a high ISO. But the slow shutter speed lets in plenty of light so I'd use a low ISO.

• It's night, so I'd usually use a low ISO. But the slow shutter speed lets in little light so I'd use a high ISO.

Multiple Choice

What ISO would you use and why?

• It's nighttime, so I'd usually use a High ISO. Also, shutter speed must have been somewhat fast to freeze the person, so not much light entered the camera. Therefore, I'd use a High ISO.

• It's nighttime, so I'd usually use a Low ISO. Also, shutter speed must have been somewhat slow to freeze the person, so not much light entered the camera. Therefore, I'd use a Low ISO.

Multiple Choice

What ISO would you use and why?

• High ISO - there isn't much light available.

• Low ISO - there isn't much light available.

• High ISO - there is plenty of light available.

• Low ISO - there is plenty of light available.

Multiple Choice

What ISO would you use?

• Low

• High

Multiple Choice

What ISO would you use and why?

• Low, there's lots of light.

• Medium, there's not a lot of light, but it's also not dark.

• High, there is lots of light available.

Multiple Choice

What ISO would you use IF you were also using a tripod?

• High, there's not a lot of light and my shutter speed needs to be fast.

• Low, there's not a lot of light but my shutter speed can be slow due to the tripod.

Multiple Choice

What ISO would you use?

• High

• Medium

• Low

Multiple Choice

What ISO would you use?

• Low

• Medium

• High