Pillars of PhotographyPillars of PhotographyShutter Speed and ISOShutter Speed and ISO

Shutter SpeedShutter Speed

Controls how long the camera’s “eye” is open.Controls how long the camera’s “eye” is open.

Measured in fractions of seconds, minutes or Measured in fractions of seconds, minutes or hourshours 1/601/60thth of a second, 1/2000 of a second, 1/2000thth of a second, etc of a second, etc

Fast shutter speeds will literally stop motion.Fast shutter speeds will literally stop motion. Water drops can be caught in mid airWater drops can be caught in mid air

Slow speeds will cause motion to blur Slow speeds will cause motion to blur Water in a stream can be made to look like milk.Water in a stream can be made to look like milk.

Types of shuttersTypes of shutters

There are three basic types of shuttersThere are three basic types of shutters Electronic ShutterElectronic Shutter

No moving parts, the sensor simply applies No moving parts, the sensor simply applies power when the release is depressed and begins power when the release is depressed and begins to record the image for the amount of time to record the image for the amount of time specified by the cameras computer.specified by the cameras computer.

Leaf ShutterLeaf Shutter Often referred to as an Iris, or Diaphragm Often referred to as an Iris, or Diaphragm

Shutter; this mechanical device copies the action Shutter; this mechanical device copies the action of your eye through overlapping metal leaves.of your eye through overlapping metal leaves.

Normally employs an odd number of leaves. Normally employs an odd number of leaves. (3, 5, 7 , etc) (3, 5, 7 , etc)

Types of shuttersTypes of shutters

Focal Plane ShutterFocal Plane Shutter Most commonly used with DSLR, (Digital Single Most commonly used with DSLR, (Digital Single

Lens Reflex), Cameras.Lens Reflex), Cameras. When release is depressed, the Front, (or First), When release is depressed, the Front, (or First),

curtain moves over the sensor until it is fully curtain moves over the sensor until it is fully open.open.

Once the shutter has been open for the desired Once the shutter has been open for the desired amount of time, the Second, (or Rear), curtain amount of time, the Second, (or Rear), curtain begins to move until the sensor is again fully begins to move until the sensor is again fully concealed.concealed.

Advanced shutter control is often called “First Advanced shutter control is often called “First Curtain Sync”, or “Second Curtain Sync” Curtain Sync”, or “Second Curtain Sync”

Shutter PriorityShutter PriorityTaking controlTaking control

Shutter PriorityShutter Priority

TV, (Time Value), for CanonTV, (Time Value), for Canon

S, (Shutter), for NikonS, (Shutter), for Nikon

Tells the camera that you are going to select Tells the camera that you are going to select the shutter speed, the camera can control the the shutter speed, the camera can control the aperture, and if needs be, the ISO.aperture, and if needs be, the ISO.

Shutter speed is the most important thing in Shutter speed is the most important thing in this image.this image.

Long shutter Long shutter speedspeed

•Often referred to as a Often referred to as a long exposurelong exposure

•Normally requires a Normally requires a tripodtripod

•Allows for deep depth of Allows for deep depth of fieldfield

•Captures motion as Captures motion as motionmotion

•Normally requires a Normally requires a smaller aperture (F16 – smaller aperture (F16 –

F22 for example)F22 for example)

Fast shutter Fast shutter speedspeed

•Can be easily hand heldCan be easily hand held•Allows you to stop motionAllows you to stop motion•Normally uses a wider Normally uses a wider

aperture (F2.8 – F 5.6 for aperture (F2.8 – F 5.6 for example)example)

•Normally will result in a Normally will result in a shallower depth of field.shallower depth of field.•Often used in sports or Often used in sports or

action shots.action shots.

The pitfallThe pitfall

Shutter speed priority will allow you to quickly Shutter speed priority will allow you to quickly select a value that can slow or stop time select a value that can slow or stop time quickly.quickly. Problem is that you may not have an aperture Problem is that you may not have an aperture

setting to allow a proper exposure.setting to allow a proper exposure.

While Shutter speed priority is handy at While Shutter speed priority is handy at times, it could result in underexposed times, it could result in underexposed images.images.

Shutter SpeedShutter SpeedQuestions?Questions?

BreakBreak15 minutes15 minutes

ISO (ASA)ISO (ASA)Speed vs qualitySpeed vs quality

What does it meanWhat does it mean

ISO, is an acronym that stands for the ISO, is an acronym that stands for the International Standards Organization. It was International Standards Organization. It was formerly known as ASA, (American Standards formerly known as ASA, (American Standards Association).Association).

This is an expression of how sensitive a This is an expression of how sensitive a sensor, or film, is to light.sensor, or film, is to light. Normal expressions are:Normal expressions are:

100, 200, 300, 400, 500, etc, etc100, 200, 300, 400, 500, etc, etc Each step is twice as sensitive to light as the last. Each step is twice as sensitive to light as the last. Problem with higher ISO is greater incident of grain Problem with higher ISO is greater incident of grain

in your image.in your image. Lower ISO generally makes for a cleaner image.Lower ISO generally makes for a cleaner image.

High ISOHigh ISO

Pumping up the ISO value will make your sensor Pumping up the ISO value will make your sensor more sensitive to light, this will allow you to take more sensitive to light, this will allow you to take pictures in darker areas without the need of a pictures in darker areas without the need of a flash.flash. This is useful in sports arenas, birthday parties and This is useful in sports arenas, birthday parties and

museums where using a flash is unwelcome, or of museums where using a flash is unwelcome, or of no use.no use.

The price you have to pay for a higher ISO is that The price you have to pay for a higher ISO is that your image will be more grainy.your image will be more grainy. Modern digital cameras are making headway Modern digital cameras are making headway

regarding this issue, however a difference can still be regarding this issue, however a difference can still be detected by the human eye on 90% of high ISO shots.detected by the human eye on 90% of high ISO shots.

Advantages of High ISOAdvantages of High ISO

Higher ISO will allow you to use a faster shutter Higher ISO will allow you to use a faster shutter speed.speed. Useful if you do not have a tripod, or you are at a Useful if you do not have a tripod, or you are at a

sporting event where the use of a tripod is sporting event where the use of a tripod is impractical.impractical.

Taking pictures at a birthday party when they are Taking pictures at a birthday party when they are blowing out candles; a flash will ruin a shot like blowing out candles; a flash will ruin a shot like this.this.

You intentionally want the grain in the shot for You intentionally want the grain in the shot for artistic reasons.artistic reasons.

Taking pictures in a confined area where only hand Taking pictures in a confined area where only hand holding will work and flash will be too powerful.holding will work and flash will be too powerful. i.e: Home inspection of an attic.i.e: Home inspection of an attic.

Example of High ISOExample of High ISO

• Shot in mixed light• Animal was moving quickly, so higher ISO was needed to support higher shutter speed at lower light.•Settings:

•ISO: 400•Shutter Speed: 1/2000 •Focal Length: 200mm•Aperture: F4

This could normally be accepted as a decent photograph, look closer, the higher ISO shows itself.

GrainGrainBringing the image to Bringing the image to

100% shows the grain in 100% shows the grain in the image.the image.

This amount of grain is This amount of grain is often deemed “Not often deemed “Not

acceptable” by most acceptable” by most professional professional

photographers, however to photographers, however to someone not in the field, someone not in the field, they would likely not care they would likely not care

unless they had something unless they had something to compare it to.to compare it to.

NORMALLY, this amount of NORMALLY, this amount of grain would not be as grain would not be as

visible in a physical print.visible in a physical print.

Slower ISOSlower ISO

You will require a longer shutter speed, as the You will require a longer shutter speed, as the sensor or film is not as sensitive to light.sensor or film is not as sensitive to light.

Depending on your situation, a tripod or other Depending on your situation, a tripod or other support will be needed or else your image will support will be needed or else your image will be blurry.be blurry. Your heartbeat can be enough to blur a shot.Your heartbeat can be enough to blur a shot.

Cleaner image, less grain.Cleaner image, less grain.

Not always the best choice for moving Not always the best choice for moving objects.objects.

Advantages of Slower Advantages of Slower ISOISO

Better detailBetter detail

Some cameras may find better color (Not Some cameras may find better color (Not always)always)

Little or no grain.Little or no grain.

Using a tripod will allow you to gain massive Using a tripod will allow you to gain massive depth of field for landscape shotsdepth of field for landscape shots

Useful for making star trails or light paintingUseful for making star trails or light painting

Best for reproduction or art shots.Best for reproduction or art shots.

Slowing it downSlowing it down• ISO: 100• Focal Length: 135mm• Shutter speed: 1/30th of a sec• Aperture: F 5.6

Clear and tack sharp, the lower ISO allows for much finer grain and recording of detail.The cost of that detail is the speed of the shutter, this image had to be shot at 1/30th of a second, which is too slow to hold by hand, even with the use of strobes.Let’s take a closer look.

Up CloseUp CloseGrain is significantly Grain is significantly

reduced due to the lower reduced due to the lower ISO.ISO.

Detail is much sharper.Detail is much sharper.The price to be paid The price to be paid

however is a shallower however is a shallower depth of field as we depth of field as we needed to open the needed to open the

aperture to get as fast as aperture to get as fast as 1/301/30thth of a sec. of a sec.

Any slower and the Any slower and the subject would likely have subject would likely have blurred due to breathing blurred due to breathing

or blinking.or blinking.

ISOISOQuestions?Questions?