CONTAINS EMBEDDED ANIMATIONS - DOWNLOAD FOR FULL EXPERIENCE! A quick recap on lenses - then some fun with shutter speeds!

1. Lenses are come in different sizes:
<30mm = wide angle
50mm = what the human eye sees
>70mm = Telephoto
Zoom = Combines all three into one
24mm 50mm 70mm

2. DOF refers to how much of a photo is in focus:
The smaller the f-number,
the smaller the DOF:

4.  In your camera – between the lens and the
film/CCD - is the shutter
Video on next
slide…

5. http://www.youtube.com/watch?v=lw6doYnO4ng

6.  Think of it as a door that opens for a split second
to allow the image of your subject to burn onto the
film/CCD…

7.  As the photographer you have control over how
long this ‘door’ is open
 Typically this will range from 1/1000th
of a second
(very, very fast) to 1 or 2 seconds (very slow)

8.  The longer the
shutter is open,
the more chance
there is that
something in
your subject will
move, for
instance…
…the train appears still

9.  But at a slower
shutter speed the
train has
travelled an inch
or so while the
shutter was
open…
…so the train blurs

10.  And at a very
slow speed the
train moves so
much that it
barely registers
on the photo…
…and becomes ghost-like

13. Notice the blurred horses’ legs

15. Faked with Motion Camera –
Android phone app
Not true motion blur
Lo Res images (480x320)

18. Notice the sharpness of the legs

19.  If you use a shutter speed slower than 1/60th
of a
second your photos will suffer from camera shake
(your hands can’t hold a camera that still for that
long!):

20. Slow
Fast
…or in old
money…

21.  For slow speeds
you’ll need a tripod:
 …or wedge your camera against something solid:

22. Fast Shutter Speed
Slow Shutter Speed

23.  Either:
 Set your camera to Shutter Priority mode and take
a series of photos of the same moving subject at
different shutter speeds
 Or, if your camera does not have Shutter Priority,
go to www.camerasim.com and experiment with
the shutter speed slider

24. A Quick Overview

25.  Opening the shutter exposes the film/CCD to light
 Too little light causes under-exposure, too much
causes over-exposure:

26.  You’ll remember that Aperture gives us Depth of
Field by changing the size of an iris in the lens:
 Think of the iris as a curtain that you can open or
close

27.  By opening or closing the iris you control the
amount of light getting through it – just like closing
a curtain to block out the sun on a bright day
 This can be used to compensate for under or over
exposure, so the iris can be opened (perhaps to
f2.8) to let in more light when using a fast shutter
speed, or the iris can be closed (f16) to let in less
light with a slow shutter speed…

32. Fast Shutter / Wide Aperture (f2.8) Slow Shutter / Narrow Aperture (f16)

33.  This is the tricky part of photography to get your
head around
 We’ll keep coming back to it over the next few
weeks
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