Anatomy of a Cel

What is a cel?
A cel in terms of animation production is a painting on cellulose acetate made to be photographed to create a frame of animation in an animated show or movie. As you know animation is actually a series of pictures that is closely correlated to depict movement on camera.

What makes up a cel?
A cel is made up of cellulose acetate and paint, thus making it mixed media. Cellulose acetate is a natural plastic that is transparent and thus used to be painted on. The paint used on cellulose acetate is usually proprietary to the studio. I’ll take this moment to say please ensure to check the preservation part of this website to understand how to care of cellulose acetate and paint correctly. Please before you go collecting understand this part first for your and your collection’s sake!

What are the holes on top?
The upper part with the holes are called “Registration holes”. They are used to keep the cels in place while being photographed and sometimes even when being painted.

What are those letters and numbers on the cel?
To the top right corner you will usually find the “Sequence Number”, this tells you what “layer” a cel belongs to and the number tells you which part of the sequence. For example if a 1 cel was labelled B3, this means that it is the second layer but the 3rd sequence of a cel. To paint a clearer picture, let’s say you have a 2 layer cel setup. Once layer is labelled A1 composing of the face and eyes of a character, while the second layer a mouth cel is B3E. This means that the first cel A1, is the first layer and the first sequence of that cel, while the B3E mouth layer is the second layer with the 3rd sequence of the mouth, while the E, indicates the end sequence.

What are those triangles or circles on a sequence number?
Those indicate a Key or primary frame sequence. Since they are key or primary frame, they are usually better drawn, looks nicer aesthetically (generally but not all the time) and thus more prized in a collection.

What is this thing written on top of my cel “Book”?
Well it’s not a book as you can see, however these words usually mean your cel is part of a Book sequence which is a more complicated setup where several cels maybe sandwiched together with an open background (imagine a window) and then another main background painting.

What is this nice thick paper painting that came with my cel?
Usually this is the production background if it came “painted” and if you can match that background and cel picture to a scene on the show. Sometimes cels will also come with a production background but it is non-matching or might not even be from the same show, it is simply paired with the cel for aesthetic reasons. You will also see color-copies of matching backgrounds and unmatching backgrounds – again usually done for aesthetic reasons. In all cases the best is to have a matching production background with the ce because this is what would be a key master setup.

But what is a production key master setup?
A key master setup is a cel that has all it’s elements and has the matching background. When i say all elements, I mean there is no missing cel layers and it comes with a matching production background. This key master setups are highly prized because they are complete representation of the scene of the show and you can match it to the show exactly.

What is this paper that has the same image and sequence as my cel?
Usually if it is an exact image and clean lines that is the douga, it is the paper representation of your cel. Essentially this is the material that was xeroxed or painted to create the lines of your cel but it also indicates the shadow areas of your cels if you look closely. If it is a different color and doesn’t exactly match your cel, this usually means it is genga, shusei (corrections), layout or roughs.

I’m confused on the sketches! I have a bunch that came with my cel! What are they?
This is a little off topic but everything usually starts with some concepts
1) Roughs – rough material usually a rough draft and sometimes for concept ddrawing
2) Layout – still somewhat rough material but usually this is drawn on studio paper along with a drawing of the background
3) Genga – usually these are on yellow paper, they represent the initial drawing where the rest of the sequence will be based
4) Shusei – these are usually in thin pink or even yellow paper, they are used to correct drawing or expression mistakes or improvements
5) Douga – this is the last drawing prior to the creation of the cel, thus their lines are exactly like the lines on your cel and has shadow information.

So these are the general anatomy of a cel. I hope it was helpful to you. I’m sure I’ve missed so much more but feel free to message me and give me more information that can help improve this page! Thank you!