Scrapping Simply

What is Shutter Speed?

Shutter Speed Is the amount of time it takes for a cameras shutter to open and close 

which is one of the three light controls when taking a picture 

ISO is a light sensitivity rating in the cameras that affects the amount of light the chip 

needs to see to take a picture. 

Higher ISO speeds are more sensitive to light, which makes them need less light to take a 

picture. ISO 100 needs twice as much light as ISO 200 and 200 needs twice as much light

as ISO 400 etc…  

If we don’t change the ISO setting on our camera for any change in shutter speed there 

must be a balancing change in aperture. If we increase the amount of light with one 

setting we must balance this by decreasing the amount of light with the other setting.  

This will give us a balanced exposure. If we need to change our shutter speed from any 

given point we must balance that by either changing the Aperture or the ISO. 

Shutter speeds that are normally used by the camera are written in whole numbers (30, 

60,125,500) but are actually fractions of seconds (1/30, 1/60, 1/250, 1/500). Full seconds 

are usually noted in cameras with the quotation symbol (“) or the number will be 

followed by an S. so 30” or 30s is actually thirty seconds where 30 is actually 1/30th of a 

second. 

Shutter speeds that a camera will most likely default too are going to fall between 30 and 

500 (1/30th to 1/500th of a second). Any slower speeds will normally activate an 

automatic flash.   

Freezing fast often requires adjusting our ISO or Shutter speed off of AUTO to get 

shutter speeds fast enough to accomplish the task. Shutter speeds adequate for most fast 

action (Sports, Dance, etc...) start at around 1/250th of a second or 250. I typically try and 

get to 1/500th of a second just to be on the safe side. ISO will almost always have to be 

adjusted indoors because of the small amount of light available. The higher the ISO 

setting the faster the available shutter speeds.  

Camera shake can be fixed by having a shutter speed faster than the focal length of the 

camera. A 300mm lens needs a shutter speed of 1/300th  (1/500) of a second or faster. A 

28mm lens needs a shutter speed of 1/28th (1/30) of a second or faster. 

Blurring movement is one of the easier things to do with a camera, but an almost 

impossible task in the AUTO modes. The amount of subject movement required to blur a 

subject is dependent on the speed of the movement, however most pictures that are 

blurred purposefully are done at shutter speeds below about 1/15th of a second and can be 

shot with exposure times well over an hour. Some of my favorite images are shot at slow 

shutter speeds. For an example blurring a rivers flowing water would normally be 

effective at 1/8th of a second or slower.  I typically start at about ½ second if that is 

possible this could either show up as a 2 or a .5” or .5s on your cameras display.  

What is Aperture?

Aperture like shutter speed and ISO is a light control and is tied to them in picture taking. 

For any given shutter speed and ISO there is only one correct aperture for a given effect.  

More critical use of aperture is done when we worry about depth of field 

Depth of field is the distance in front of and behind you subject which is still sharp 

1/3 of the depth of field is in front of your focusing point 2/3 of your depth of field falls 

behind your focusing point.  

Smaller numbers represent a larger opening which lets in more light and will give you 

faster shutter speeds. Larger numbers are a smaller hole thus you get slower shutter 

speeds. Smaller numbers give you a smaller depth of field. Larger numbers give you a 

larger depth of field.  

Portraiture is typically done using a small aperture setting to blur the background 

The closer you get to the subject the easier it is to blur the background. And the harder it 

is to get the background clear. 

If your subject is on a flat plane (wall behind subject) you will have a hard time bluring 

the background 

Smaller cameras have an easier time making the background clear, but a harder time 

blurring the background. (hint: Get close) 

Aperture can be used to control shutter speed, and can also be used to create star filter 

effects at night.