FRAMEBURST ACADEMY 23
Summary (TL;DR)
Most beginners think animation is just drawing lots of pictures.
It is not.
The real magic is how things move between those pictures.
Today you will learn:
- What Slow In and Slow Out actually mean.
- Why objects almost never start or stop moving instantly.
- What arcs are and why animators obsess over them.
- Why does movement that follows curves feel natural?
- Why does animation look robotic when everything moves in straight lines.
- How to instantly improve your animations even if you can barely draw.
By the end of this lesson, you will start noticing movement differently in real life. You’ll see animation principles happening everywhere – from people waving their hands to birds flying to someone simply picking up a cup of tea.
And once you see it, you cannot unsee it.
🎬 What Is The Difference Between Slow In And Slow Out?
Imagine you’re sitting in a parked car.
The driver suddenly presses the accelerator.
Does the car immediately jump from 0 km/h to 60 km/h?
No.
It starts slowly.
Then speeds up.
Now imagine the driver wants to stop.
Does the car instantly freeze?
Again, no.
It slows down gradually before stopping.
This is exactly where Slow In and Slow Out come from.
Most things in real life do not instantly start moving or instantly stop moving.
They gradually build speed and gradually lose speed.
Animation copies this behavior.
Slow Out: Starting Movement
When an object begins moving, it usually starts slowly.
Then it gains speed.
This is called Slow Out.
Why “out”?
Because the object is moving out of its starting position.
Think about:
- Standing up from a chair
- Throwing a ball
- Opening a door
* Starting a run
Nothing instantly reaches full speed.
Everything builds momentum.
In animation, this means:
You place more frames near the starting pose.
The object spends a little more time there before speeding away.
Slow In: Ending Movement
Now let’s look at the other side.
Imagine catching a ball.
Your hand does not instantly stop.
It slows down before settling.
This is called Slow In.
Why “in”?
Because the object is moving into its final position.
Examples:
- Sitting down
- Closing a laptop
- Landing after a jump
- Putting a cup on a table
Objects usually reduce speed before stopping.
In animation, this means:
You place more frames near the ending pose.
The movement gradually settles into place.
The Easiest Way To Remember It:
A simple trick:
Slow Out = Leaving Home
Slow In = Arriving Home
Leaving takes time.
Arriving takes time.
The middle is usually where movement is fastest.
What Happens If You Do Not Utilize Slow In And Slow Out?
Let’s say you are animating a character raising their arm.
Frame 1:
Arm down.
Frame 2:
Halfway up.
Frame 3:
Arm fully up.
Every frame is equally spaced.
The movement technically works.
But it feels weird.
Why?
Because the arm appears to move at exactly the same speed throughout.
Humans rarely move like that.
The result feels:
- Lifeless
- Robotic
- Artificial
- Mechanical
This is one of the biggest reasons beginner animation looks stiff.
Not because of bad drawing.
Because of bad timing.
Real life Loves Acceleration & Deceleration:
Here’s something important.
Nature hates instant speed changes.
Everything has weight.
Everything has momentum.
Everything resists change.
That’s why:
- Cars accelerate.
- People accelerate.
- Animals accelerate.
- Falling objects accelerate.
Likewise:
- Birds land.
- Cars brake.
- Balls roll to a stop.
- People slow down.
Slow In and Slow Out are simply animation’s way of copying reality.
🧩 What are Arcs?
Now let’s talk about something that secretly controls almost every movement around you.
Arcs.
An arc is a curved path of movement.
Instead of moving like this:
A → B
Movement often goes like this:
A ↗ B
OR
A ⤴ B
A curved path.
Look At Your Own Hand:
Hold your finger in the air.
Now move it from one side to another.
Did it travel in a perfectly straight line?
Possibly not.
Your shoulder rotates.
Your elbow bends.
Your wrist moves.
All of these joints create curves.
This naturally produces arcs.
Why Animators Care So Much About Arcs:
Because living things are built from joints.
And joints create curved movement.
Humans move in arcs.
Dogs move in arcs.
Birds move in arcs.
Fish move in arcs.
Even tree branches move in arcs when the wind blows.
When movement follows an arc, it feels alive.
When movement ignores arcs, it often feels robotic.
Straight Lines Are Rare In Nature:
Look around you.
A baseball pitch curves.
A bird glides through the air.
A person waves.
A cat jumps.
A leaf falls.
Almost nothing moves in a perfectly straight line.
Straight-line movement is actually harder to find in nature than curved movement.
Yet beginners often animate everything in straight paths.
Why?
Because it is easier to draw.
Unfortunately, easy does not always look good.
Curve Motion Creates Beauty:
Imagine two animations.
Animation A:
The hand moves in a straight line.
Animation B:
The hand follows a gentle curve.
Most people will prefer Animation B.
Even if they don’t know why.
Curves feel elegant.
Curves feel natural.
Curves feel organic.
Your brain sees them every day in real life.
Natural Movement Flow:
Now let’s connect everything together.
Slow In.
Slow Out.
Arcs.
Curve motion.
What do they all create?
Flow.
Flow is when movement feels smooth and believable.
The audience stops noticing the animation.
They simply believe it.
Good flow feels effortless.
Bad flow feels awkward.
The audience may not know what’s wrong.
But they’ll feel something is off.
Real-life Example:
Imagine a character reaching for a glass of water.
Bad Animation:
- Hand starts instantly.
- Hand moves in a straight line.
- Hand stops instantly.
Everything feels mechanical.
Now let’s improve it.
Good Animation:
- The hand slowly starts moving.
- It accelerates.
- It follows a curved path.
- It slows down before grabbing the glass.
Same action.
Huge difference.
One looks like a robot.
The other looks alive.
The Secret Observation Exercise:
This week, do not animate immediately.
Observe.
Watch people.
Watch animals.
Watch yourself.
Notice:
- How people walk.
- How they sit down.
- How they stand up.
- How they pick up objects.
- How they wave their hands.
Ask yourself:
“Did that movement start instantly?”
“Did it stop instantly?”
“Did it travel in a straight line?”
You will quickly discover the answer is usually no.
This observation habit is what slowly transforms beginners into animators.
Common Beginner Mistakes:
Mistake #1: Equal Spacing Everywhere
Every frame is spaced exactly the same.
Result:
Robot movement.
Mistake #2: Perfectly Straight Motion
The character’s hand, head, and body all travel in straight paths.
Result:
Stiff animation.
Mistake #3: Instant Stops
The movement suddenly freezes.
Result:
Feels unnatural.
Mistake #4: Ignore Reality
Animating from imagination only.
Result:
Guessing instead of understanding.
The Final Thoughts:
If you remember only one thing from this entire lesson, remember this:
Life rarely moves in perfectly straight lines and almost never starts or stops instantly.
Things speed up.
Things slow down.
Things follow curves.
Things flow.
When your animation starts copying those behaviors, it immediately begins feeling more alive.
Not because you became a better artist overnight.
But because you started understanding how movement actually works.
⏭️ What’s Your Next Step (Coming Thursday):
Today, we learnt why animation timing and spacing is more important than drawing skills.
Most beginners think better drawings create better animation.
The truth is far more surprising.
Next Blog: We’ll explore why a stick figure with great timing can look more alive than a beautiful character drawn by a beginner.
You’ll learn:
- What timing actually is.
- Why timing controls emotion.
- Why comedy lives and dies by timing.
- Why action scenes feel powerful.
- Why do some animations feel boring even when the art looks amazing?
- The beginner timing exercise that instantly improves animation.
And trust me…
This lesson changes how you look at animation forever.
See you until the next summon. 🎬