centre for animation & interactive media

Animation Tech Notes #2
'Dope' Sheets or Exposure Sheets
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EXPOSURE SHEETS - what do they do?
Any traditional 'cel' animation is likely to consist of hundreds, if not hundreds of thousands of individual painted cels or images. The assembly-like hierarchy developed by the large animation studios in the heyday of character animation in the 1930's and 40's, required a fastidious and precise system for recording the sequence and order of various cel layers, the number of exposures given to these layers, and the movements of camera, background, or compound.

The 'exposure sheet' was devised as a method of accounting for all these components. In practice, all this information is written down on this sheet by the animator. The exposure sheet and its 'mark-up' language is also a means of communicating the animator's intent right throughout the production chain. <click here> for an example of this record-keeping device.

Exposure sheets are not only used by large animation studios, however. They are also extensively used by independent animators as a personal aid in the planning, creation and timing of their work as a means to chart up and keep track of the progression of events.

WHAT DO THEY LOOK LIKE?
Exposure sheets consist of a series of horizontal lines and vertical columns. The first column contains consecutive numbering which accounts for each and every frame within the finished movie. The exposure sheets we use have 100 frames on each sheet, or 4 seconds of screen time at the television frame rate of 25 per second. In order to keep a running count of frames, the animator simply adds the appropriate prefix numbers before each zero on every new page.

Other columns are labelled D, C, B and A (reading from left to right) and refer to the order of cel layers. Cels on level A are placed on the pegs first and is therefore furthest from the camera and closest to the background. If possible, the animator positions those cels that require the most frequent changing at the top of the pile. The background is usually given a letter reference or a short descriptive term in order to differentiate between the various backgrounds used within an animation. e.g. BG1, BG2 etc.

Reading across any horizontal line will tell the camera operator which particular combination of cels and in what order, will be required to make up the image of each frame of film.

The exact timing and position of each cel is indicated by the individual cel's number, and this is placed on the exposure sheet in a box beneath its appropriate cel layer. Usually the animator employs both a letter and a number in marking individual cels. The letter is sometimes chosen to indicate the subject matter of the cel series. 'H' might be for the head overlay, 'F' for feet, 'HA' for hat, etc. In Australian animation studios, it is more usual that each drawing carries the same letter as the level it will be placed in under the animation camera. The number beside the letter indicates the order of cels for each layer (Al, A2, A3, A4, etc.).

The exposure sheet has a column on the far right for camera instructions such as fades, dissolves, superimpositions, and for camera/compound movements such as pans, zooms, and spins. In addition there is a column in which the animator can chart up events that are determined by a prerecorded sound-track or to note for further reference any item that might easily be forgotten or wrongly executed.

 

 

 

An animator working out timings with a stopwatch, dialogue analysis, and thumbnail sketches from the storyboard.

For a typical example of a 'dope' sheet
<click here>
COMPUTER INTERFACES
Most computer programs which deal with layered time-based imagery have used the method and metaphor of the traditional animator's 'exposure sheet' as an interface device - if it works so well, why change it? However their timelines usually run across the computer screen rather than vertically down. For a typical example of a 'dope' sheet <click here>.
 


Read on....



Sources and Other References:

See also: Tools of the Trade


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