Editing Animation Timing with the Dope Sheet
The Dope Sheet is one of the editors in the Animation Panel. It's used to change the timing for animations. Timing is basically "when things happen". For example you might want to change when an animation starts or how long it lasts. The Dope Sheet is specifically aimed at making these sorts of changes. When you edit animation keys with the Dope Sheet you are only changing the frame positions of those keys, not the values. This makes it easy to change animation timing without effecting the values of keys.
In case you're wondering the name "dope sheet" comes from traditional animation. The dope sheet, also known as an exposure sheet, is a document that helps an animator organise their animation and also give instructions to the cameramen who are filming the animation.
Overview
The Dope Sheet view shows consists of rows. Each row corresponds to an item in the node list to the left. A row contains all the keys for a corresponding parameter or component of that parameter.
Some of the items in the node list are for the nodes themselves. These rows don't have any keys as, of course, you animate parameters of nodes and not the nodes themselves. You can expand a node item in the list to show the all the animated parameters for that node.
The keys for parameters are shown as white diamonds in the corresponding row in the Dope Sheet view. Some parameters have multiple components, such as vector or colour parameters, and you can set keys on the individual components. In this case the keys in the row for the parameter are coloured yellow. This are special keys called metakeys. You can find out more about metakeys here. If you expand the parameter list item you will see new rows in the Dope Sheet for each component.
Moving keys
Moving keys is the way to change when things happen in an animation. Let's say you have an animation which starts at frame 10, but you want it to start at frame 20. Simply double click on the range bar for the parameter to select all the keys and then drag the keys so the first key is at frame 20.
You also change when particular parts of an animation happen. All you need to do is select the keys relating to that part of the animation and then move them to when you want it to happen.
Scaling keys
You can scale keys to change the length of an animation while still keeping the time between keys in the same proportion. You can stretch all or part of animation out to take longer or you can squeeze it down to make it shorter. You can scale keys interactively, by selecting keys and dragging them, or more precisely using the Action button.
The Dope Sheet has two scaling methods. The first is scaling about the frame cursor. This is the most versatile scaling method. First you move the frame cursor to the location you want scaling to start from. Let's say you want to stretch an animation out. You'd move the frame cursor to the first key.
The other scaling method is scaling about the centre of the selected keys. Scaling will happen about the middle of the keys you've selected. Here's an example:
!!!MOVIE!!!
Reversing keys
You can easily reverse an animation or, in other words, flip it end for end. Reversing is a special form of scaling. There are a couple of ways to reverse an animation.
The easiest way is to use the Action button:
- Select all the the keys.
- Enter -100 in the Action edit field.
- Click the Action button and choose Scale keys from centre of keys.
This will flip the keys "in place" without otherwise changing their timings.
The other way to reverse keys is to scale them interactively. As mentioned above there are two scaling methods in the Dope Sheet - scaling about the frame cursor and scaling about the centre of the selected keys. Whenever you drag past the location you're scaling about the keys will be reversed. For example lets say you're scaling about the frame cursor. You start dragging one of the keys on the right of the frame cursor. If you drag the key to the left side of the frame cursor the animation will be reversed.