Upcoming
Deadlines
Pick up a
clicker.
Second Homework (Mini-portfolio):
Due Thursday, Aug. 30th (This week)
10 points (5 points if late)
Third Homework (Shooting Reference)
Due Tuesday, Sept. 4th (Next week)
For full schedule, visit course website:
Animation123.com
Homework Assignment #2
Make an entry in your course blog called "MiniPortfolio" to post images and movies showing
some examples of your work in animation or
illustration (if any).
Also tell me a little bit about yourself, such as
your major, what courses you've taken in art
and in science, what you're taking now, what
you're interested in doing when you finish
school, etc.
Homework #2 (cont.)
You will not be graded on the quality of the
work; some of you have extensive portfolios
while others are just starting (or have no
experience at all).
The purpose of this assignment is two-fold:
First, it gives you some practice editing your
blog, in particular uploading images and
movies. Second, it gives me (and your
classmates) a chance to get to know you.
Homework #2 (cont.)
Assignment Checklist
* Created post entitled "Mini-Portfolio" on your
personal blog for this course.
* Uploaded at least two images, preferably but
not necessarily your own work.
* Uploaded at least one video clip, preferably
but not necessarily your own work.
* Included a paragraph describing yourself,
especially your academic work.
Homework #2 (cont.)
This assignment is due by 8am on
Thursday, August 30th (This week)
Don’t forget to visit the course website and go to
the Assignment section to submit the URL for
the blog post with your mini-portfolio.
Extra Credit Opportunity
Attend a screening at the
SF Shorts International
Film Festival,
San Francisco.
Festival runs Sept. 6-8th
Turn in proof of attendance
(ticket receipt) for 10 points
extra credit.
For info: www.sfshorts.org
Extra Credit Opportunity
Visit the Cartoon Art
Museum in SF to see the
Avengers Assemble!
exhibition.
Exhibit runs until Oct. 7th
Turn in proof of attendance
(ticket receipt) for 10 points
extra credit.
For info: cartoonart.org
i>Clickers
We will be using i>Clickers for
class participation.
Keep your clicker and bring it
with you to every class.
At the end of the semester
you will return the clicker.
Using your i>Clicker
Turn on your clicker. Should see:
AA
[Clicker ID Number]
Then
POA 123
Then
READY
Survey Question
What is your major?
A) Animation / Illustration major
B) Art major but not A / I
C) Science or engineering major
D) None of the above
Enter your answer
Will see a check mark
Can change answer
Survey Question
How much time did you spend on the first
homework (create a blog)?
A) Less than 30 minutes
B) An hour or so
C) Several hours
D) Did not get it done yet
Get participation
points for survey
questions,
regardless of your
answer.
Survey Question
You have already done the second
homework (mini-portfolio).
True (Press A) or False (Press B)
Registering your Clicker
After today’s class, go online and register your
clicker at:
http://www.iclicker.com/support/registeryourclicker/
This link is also listed on the course website.
Put your name and phone number on your
clicker (use masking tape) in case you
misplace it.
Clicker Questions in Class
Keep your clicker handy during class; you’ll be
asked quiz questions from time to time.
During these quizzes you may talk to other
persons to discuss the question. The point is
for you to learn rather than just testing.
May turn off clicker between questions.
Each class will start with a survey question and
quiz questions so be on time!
Physics of Falling
Part I
Ball Drop Animation Exercise
Typically the first example one
looks at in animation is falling
motion, such as a falling ball.
In this exercise, the drawing
couldn’t be simpler. It’s just the
same round ball in every drawing.
Nevertheless, animating the ball so
that it moves realistically can still be
a challenge. But the challenge is
not in how you draw the ball but
where it is drawn on each frame.
Ball Drop in Animation Books
The ball drop is
discussed in every
major textbook for
animation.
Why is this example
considered so important?
It’s all in the timing…
An essential element of animation is the timing and
spacing between drawings
“It’s not important
what goes on
each frame of
film; it’s the
spaces between
the frames that
are important. “
Norman McLaren
Oscar winning
animator of
Neighbors
Principles of Animation
In The Illusion of Life, Frank Thomas
and Olie Johnston list a set of basic
principles for animation.
1.
2.
3.
4.
5.
Squash & Stretch
7. Slow In and Slow Out
Timing
8. Arcs
Anticipation
9. Exaggeration
Staging
10.Secondary Action
Follow Through
11. Appeal
& Overlapping Action
6. Straight Ahead & Pose-to-Pose Action
Principles of Timing and Spacing
The principles of timing and spacing
used to create a believable ball drop
apply to many other types of motion,
even character animation such as a
jumping cat or effects animation such
as a stream of water.
Timing: Frames, Keys, & Clocks
We use three different ways of measuring time:
• Frames (intervals of 1/24th of a second)
• Keys (given number of frames between poses)
• Clocks (actual seconds as measured by a clock)
For example, you may “slug out” a scene using a
stop watch, then convert that into a number of key
poses, which appear as frames on your dope sheet
(also called an exposure sheet or X sheet).
Frames per Second (FPS)
Frame rate is measured in frames per
second (FPS). Two common frame rates:
24 FPS – Used in film
30 FPS – Used in video
We will always use 24 FPS in our examples
and convert to video frame rate if needed.
(4 Frames of Film) = (5 Frames of Video)
Frames between Keys
Here are the key poses in a jump with the drawings
“shot on threes”, that is, three frames per drawing.
#3
#2
#1
#4
#5
IMPORTANT: For simplicity, in all our examples the key poses will
always have an equal number of frames between each key.
Dope Sheets
Dope sheets (also called exposure sheets or
X-sheets) are used by animators to tabulate
which drawing goes on which frame.
#3
Dope Sheet
Frame
Key
1
#1
2
|
3
|
4
#2
5
|
6
|
7
#3
8
|
#2
#4
#1
An animator using a dope
sheet, including dialogue
analysis and thumbnail
storyboard sketches.
#5
Uniform Motion
The simplest type of motion is uniform motion; a
heavy ball rolling on a table is a good example.
In uniform motion, the velocity is constant so the
spacing from frame to frame is constant.
Larger the spacing, the faster the ball is moving.
Uniform Motion & Speed
The timing and spacing determine speed.
This bowling ball is 12
inches in diameter with
two frames per drawing
(shooting on twos).
What is the speed of the
bowling ball?
10 miles per hour
7 inches per frame
20 miles per hour
15 inches per frame
30 miles per hour
22 inches per frame
40 miles per hour
29 inches per frame
50 miles per hour
37 inches per frame
60 miles per hour
44 inches per frame
90 miles per hour
66 inches per frame
The ball rolls about 20 inches
per drawing so 10 inches per
frame so about 15 m.p.h.
Wile E. Coyote on Rocket Skates
http://www.youtube.com/watch?v=p4YxdXw9evc
Let’s estimate his speed in this scene from “Beep Beep”
Quiz Question
What would you guess is Wile’s
speed?
A) 20 m.p.h.
B) 40 m.p.h.
C)60 m.p.h.
D)80 m.p.h.
E) 100 m.p.h.
Estimating Wile’s Speed
He travels about the length of
his ears (say 12-15 inches) per
frame so he’s only going about
20 m.p.h.
Frame 717
10 miles per hour
7 inches per frame
20 miles per hour
15 inches per frame
30 miles per hour
22 inches per frame
40 miles per hour
29 inches per frame
50 miles per hour
37 inches per frame
60 miles per hour
44 inches per frame
90 miles per hour
66 inches per frame
Frame 718
*Correction of 20% since movie is 30 fps
instead of 24 fps; going 24 m.p.h.
Slowing In (or Easing In)
If an object’s motion is not uniform, the object is either
speeding up, slowing down, or changing direction.
If the speed is decreasing then the spacing between
drawings decreases, which in animation is called
“slowing in” (or “easing in”).
Slowing
In
A sled slowing by friction is a simple example of slowing in.
Slowing Out (or Easing Out)
Slowing
Out
A ball rolling down an incline is
an example of slowing out.
Slowing Out
If the speed is increasing then the
spacing between drawings increases,
which in animation is called “slowing
out” (or “easing out”).
A ball falling downward
is another example of
slowing out.
Principles of Animation
Slowing in and out is another one
of the principles of animation.
1.
2.
3.
4.
5.
Squash & Stretch
7. Slow In and Slow Out
Timing
8. Arcs
Anticipation
9. Exaggeration
Staging
10.Secondary Action
Follow Through
11. Appeal
& Overlapping Action
6. Straight Ahead & Pose-to-Pose Action
Ball Drop Animation Exercise
Let’s look at the ball drop in detail, first
looking at the motion as the ball slows
out from the apex.
First, we’ll
carefully observe
the motion, both
live and with video
reference.
Apex
Ball Drop Video Reference
Falling occurs quickly so it’s difficult to see details.
http://www.youtube.com/watch?v=YSqkulTyaNY
Ball Drop Video Reference
This is in slow-motion, at one-quarter the normal speed.
http://www.youtube.com/watch?v=vHYuAz6sY4k
Distance Fallen from an Apex
Distance fallen
from the drawing at
the highest point
(called the apex) is
given by this table.
The formula to compute
this table is:
(Distance in inches) =
(Number of Frames) x
(Number of Frames) x
(1/3 inch)
Time
(seconds)
Frames
Distance fallen
from apex
1/
24
1
1/
3
1/
12
2
1 1/3 inches
1/
8
3
3 inches
1/
6
4
5 1/3 inches
¼
6
1 foot
1/
3
8
1 ¾ feet
½
12
4 feet
2/
3
16
7 feet
¾
18
9 feet
1
24
16 feet
inch
Planning a Scene
#2?
For a ball drop from a
height of 4 feet it takes
12 frames from the
apex to the ground.
“Shooting on twos” the
dope sheet is this 
Key #1 is the apex
Key #7 is the ground
Where should the ball be
on keys #2 through #6?
Frame
Frame
Key
Key
1
1
#1
#1
2
2
/?
3
3
?
#2
4
4
/?
5
5
?
#3
6
6
/?
7
7
?
#4
8
8
/?
9
9
?
#5
10
10
/?
11
11
?
#6
12
12
/?
13
13
?
#7
#3?
#4?
#5?
#6?
Straight-Ahead Animation
In Straight-Ahead animation, you have a first drawing and
a rough idea of what you want for action.
First drawing
Images in your head
Next, we want to
have some idea
as to how many
drawings will take
us from this first
key pose to that
conclusion of the
action
Straight-Ahead Animation (cont.)
In Straight-Ahead animation, the next step is to decide on
the second drawing and draw that frame.
First drawing
Images in your head
Second drawing
Quiz Question
The first key is when the ball is
released and the second key is
two frames later (since we’re
“shooting on twos”).
About where will the ball be on the
second key?
A, B, C, or D?
Ball is 4 inches
in diameter
A)
B)
C)
D)
Time
(seconds)
Frames
Distance fallen
from apex
1/
24
1
1/
1/
12
2
1 1/3 inches
1/
8
3
3 inches
1/
6
4
5 1/3 inches
3
inch
Straight-Ahead for Ball Drop
B)
The table tells us that after two
frames the ball falls by 1 1/3
inches, a third of its diameter
of 4 inches.
Time
(seconds)
Frames
Distance fallen
from apex
1/
24
1
1/
1/
12
2
1 1/3 inches
1/
8
3
3 inches
1/
6
4
5 1/3 inches
3
inch
B)
Ball diameter is
4 inches
Home Demo: Catch a Buck
Take a one dollar bill and
have a friend put their thumb
and index fingers near
Washington’s head. At
random, let go of the dollar.
Can your friend react fast
enough to catch the money?
Quiz Question
What is the slowest reaction time
that still allows you to catch the
dollar?
A) 1/24th second
B) 1/12th second
C) 1/8th second
D) 1/4th second
E) ½ second
Reaction Time to Catch a Buck
C) 1/8th second
Half length of dollar bill is 3
inch so it takes about 1/8 of a
second (0.125 seconds) to
fall this distance.
Typical reaction time is 0.20
to 0.25 seconds so most
people cannot catch the
dollar.
Measuring Reaction Time
Distance (inches)
1
2
3
4
5
6
7
8
10
12
14
16
18
Time (sec.)
0.07
0.10
0.12
0.14
0.16
0.17
0.19
0.20
0.23
0.25
0.27
0.29
0.30
Release
Catch
Slugging and Reaction Time
In planning a scene, you may
use a stopwatch to time it as
acted out in live action (called
“slugging” a scene).
Your reaction time is about a 1/4
second delay so should you
subtract that much from your
stopwatch reading?
No, because there’s a reaction time delay in hitting
START but also in hitting STOP.
Distance Fallen and Weight
The distance that an object falls does not
depend on its weight so long as the force of
air resistance is minimal.
A softball and a
bowling ball fall
together when
released from the
same apex.
Straight-Ahead for Ball Drop
The table also tells us that
after four frames the ball
falls 5 1/3 inches so that’s its
position from the apex for
key #3.
Time
(sec)
Frames
Distance
fallen
from apex
1/
24
1
1/
1/
12
2
1 1/3 inches
1/
8
3
3 inches
1/
6
4
5 1/3 inches
This is correct but measuring
the position for every drawing is
a very boring and tedious way to
animate!
3
inch
Apex
2 frames
4 frames
6 frames
Seeing the Rhythm
It’s good to know
how quickly
objects fall but
animators do not
calculate the
motion.
Animators see the
patterns in how
the motion slows
in and out.
From Preston Blair’s, Cartoon Animation
The “Odd” Rule
For a falling object, the
distance between drawings
follows a simple pattern,
which we’ll call “The Odd
Rule” because it uses the
odd numbers, 1, 3, 5, 7, etc.
Distance between keys
increases in the ratios
1:3:5:7:9… starting from the
apex drawing (key #1).
Rolling Downhill
Key #1 is point of release
Rolling downhill is
also accelerating motion
Very similar to falling except distances are
smaller and depend on the slope of the incline.
But the distances always go as 1:3:5:7:9:etc.
Class Demo: Galileo’s Ramps
Roll wheels down notched, inclined
ramps and listen for the clicks.
8
8
8
8
8
8
8
8
Click-----Click----Click---Click--Click-ClickClick
Downhill
Start
Click--Click--Click--Click--Click--Click--Click
1 3
5
7
9
11
13
15
Deceleration by Friction
Spacings when decelerating by friction
also follow the Odd Rule, slowing into the
final key (coming to a stop).
#1
#2
#3
#4
Many (but not all) cases of slowing in/out follow the “Odd Rule”
Odd Rule “Rhythm”
Learn to
recognize the
spacing “rhythm”
of the odd rule for
slowing in and
slowing out.
Apex
1
3
5
Quiz Question
Which of
these
spacings
has the
proportions
of the Odd
Rule?
A)
B)
C)
D)
Odd Rule “Rhythm”
1
With practice
you’ll easily
recognize
the Odd Rule
rhythm.
3
5
A)
B)
C)
D)
Quiz Question
We know that key #2 is a third of
the ball’s diameter below key #1
(point of release or apex).
A)
B)
Roughly where do you draw
the ball on key #3?
C)
D)
Straight-Ahead for Ball Drop
C)
By the Odd Rule the spacing
between keys #2 and #3 is three
times the distance from #1 to #2.
So key #3 is one diameter lower
than key #2.
C)
It’s easy to estimate this
1-to-3 ratio in the
spacings by eye.
Next Lecture
Physics of Falling
Part II
By this Thursday (August 30th):
Complete the 2nd homework
(Post a mini-portfolio on your blog)
Turn off clickers; bring them to every class