0. Cel
Cel painting is a classical animation practice where you ink and paint clear acetate sheets and layer them with other cels or backgrounds. We see the ghosts of this process in software like Toon Boom’s Harmony or in some hybridized trad-digital workflows in independent animation.
I worry the myth that cel is a luxury process reserved for the high budget animator is scaring a lot of artists away from trying out this cool process. I have made works on cel for little to no cost with a combination of material knowledge and rethinking how I use cel and I think you can too!
I’ll use some production images from my 3-channel work, “Pine Processionary” to show how I work on cel. PP was my first work on cel back in 2018.
1. Overview
I know from experience that the hardest part of cel is figuring out the materials and workflow so I’m going to do the technical breakdown for you. Before digging in here, you should flip through this really thorough guide by Ingo Raschka on cel processes with a digital angle. They cover a lot of the history and adapt cel workflows for digital processes very well. Also drop by DIY Animation’s blog for more info. Dave is has cleanliness and cel hygiene down to an art! I am messy and you might find some of my process overlooks some habits you might want to adopt. I want to suggest a few new shortcuts with a focus on low budget and tech accessibility here. I’ll put some tech notes in the bottom for anyone who is newer to my tutorials.
2. Shopping/Recycling Materials
Buying Ink: I like to ink by hand. I’ll get into some strategy later but as far as picking an ink, you’ll want something crusty, opaque and appropriate for the pen or brush you are using. I use Dr. Ph. Martin's Black Star Waterproof India Ink Hicarb. I have seen it at local art stores for closer to $7. You can also check the stats on Jetpens and find something similar. What I like about the doctor’s ink is that it runs a super clean line and dries fairly fast (this is important for when you need to stack cels to trace). It sits slightly proud on the cel which is good for durability under the paint layer. You can also scrape it off which is fun if you mess up or you want to add some film-scratch textures.
Buying a Pen: I combine doctor ink with a dip pen. DO NOT put this ink in a fountain pen! I like to use these nibs with a nib holder like this. This combo is a “dip pen.” You will also want something inkwell shaped to dip into. You can probably find something around your house like the long plastic caps that are on spray mister bottles. You’re resourceful! The nibs may seem a bit pricey but you can use them forever despite what people say. I drop them into rubbing alcohol immediately after using them and keep them super clean. Damaged or dull ones I set aside to use for different line weights. Totally bypass needing a dip pen by using a small brush.
Buying Paint: This is probably where you will do the most exploring. I like to use Holbein acrylic gouache because of the color range but it isn’t as smooth as traditional cel paint. It is also quite expensive. I’ve also tried pigmenting white screen-printing ink I found in a dumpster and that worked fairly well. I encourage you to explore in this area. I’ve heard rumours about sign paint, nail polish, etc. Traditional cel paint is vinyl-based I think so it is stretchy. You can use this as a clue in your search. Chances are your roommate’s acrylic paint will work just fine. Please practice material safety and please do NOT put acrylic paint down the sink.
Buying/Finding Cel: A lot of people use overhead transparencies. This is great because they are cheap and you can get some really good mileage. I have used discarded plastic sheets a painter friend had collected for me from packaging on canvases at a wine and painting gig he worked. Recycle found plastic sheets if you can! ONE DISCLAIMER: Real cel is stretchy. It bends with the ink as it dries and ages. If you work on overhead sheets or found plastic, the ink and paint may crack and age poorly. Maybe it won’t! I happened across a generous donation of real cel that got me through my biggest cel projects but you can invest in cel at Lightfoot. Get 10f (copy paper sized) instead of 12f (bigger) unless you have a good reason. If you have a trad animator in your region it could be worth asking if they have cel lying around that they won’t be using. You can also work in the margins of used cel and edit out the old stuff or even wash cel.
You’ll see later that I encourage you to rethink the way you use cel to be resourceful. Sure, $70 for 100 sheets is a lot but I can’t remember the last time I made an animation that was even 100 frames long! I encourage you to do the 10 for $10 and try a small loop. Other ideas at the bottom of this page.
A note on LF, it was really frustrating shipping to Canada with them. If you are outside of the US, just keep this in mind and maybe seek alternatives. Sometimes I see cel on Ebay or CL. I would often ship it within the US and carry it back on the plane with me after visiting to save like $100.
Another note: I absolutely love the weird tissue paper they put between cels. It’s one of my favourite surfaces for illustrating on. It is punched so you can also use this for animating on if you are wild.
Gloves: You will see white cotton gloves suggested as mandatory for working with cel. The idea here is that your greasy little hands will keep the ink and paint from sticking. I haven’t found this to be much of an issue. I see buying special gloves as a weird barrier to working on cel so I use the nitrile gloves I use for dying hair but I have also used a knit winter glove with some of the fingers cut off. Maybe even an old sock would work because you mostly need to protect the cel from where you rest your hand as you draw. You can also just wash your hands well and touch the cel. You’ll be ok.
Glove Concept 1
Glove Concept 2
3. Process: Ink and Paint Dept
Process: Inking
There are two main ways to ink cel by hand. If you are a planner you may want to pencil out your scene on the paper between cels and then ink over the paper one at a time. I am very straight-ahead and love tracing cel to cel for Extreme Precision. This method gets a little messy though. I keep the paper between the cel as I trace. This helps sponge up any ink that didn’t dry all the way and keeps it off the cel being traced onto and it creates and onion-skin effect to help see which layer lines are on.
You’ll notice the ink will dry really fast on the nib which you’ll just have to get used to. I keep little squares of cut up cotton t-shirts dipped in water to wipe my nib if I pause. This keeps the ink from clumping all over the nib and messing with line weight. I switch the nib every 15 min or so for a fresh one, dropping the old one in alcohol to soak before cleaning. Try not to let the nibs sit in water or dry in the open with water because they will rust. Alcohol won’t rust.
Cel, even with the tissue between, is generally thin enough that you can work without a light table. You may find a small $20-30 led light pad useful though.
Process: Painting
Production shots from Pine Processionary
Ok this might seem silly to write out but sometimes this gets missed. You paint behind the line. This is the same concept as paintings on restaurant windows at Christmas. The line becomes buried under the paint creating really nice clean lines. Then you will shoot the cel from the side opposite from the ink and paint. You can play around with this layering of course. I once shot the back of “Pine Processionary” just out of curiosity.
I like to paint by laying out all the cels on a big table and then one color at a time just slapping the paint on. Ingo details really well in their guide how to plan the layers of paint.
4. Capture
If you have access to an artist run centre or university with an animation stand with a good lighting setup then by all means shoot on that! Most of us don’t. I scan my cels because I am a scanimator. It eliminates the need for complex lighting (cel is reflective so shooting it under camera requires careful lighting). Scanning also keeps the art flat. It’s a little funny because I add the background back in digitally when you would usually work on cel to shoot it layered over the background. Whatever, it’s not 1970 we can do what we want. You can patch this together with my paper compositing tutorial to remove your animation from the scanner lid.
If you are scanning, PLEASE do a color test of how your paints look in your scanner BEFORE you paint. Cheap scanners will have no regard for your nice paint.
For short-form works on cel I have had success just tacking the sheets to the wall and shooting them with my camera.
5. Strategies for efficiency and cost-cutting
OK now that we have the basics down, let’s totally rethink this all with cost and material efficiency in mind. It might feel like a gimmick that my big secret to making cel cheap is working in short-form format but we see this also in say 16mm film production where an artist will cut film footage into digital footage to use it as a spot treatment so why not treat cel as something to sprinkle in.
Work really small. I see a lot of rotoscope cel painters use this strategy. They’ll fit 6 or 8 frames per sheet instead of one frame per sheet. This saves a ton of cel and gives you a constraint to work within which is fun.
Use my crosshair method on cel. This means you are only using 2 sheets of cel but you get a whole loop!
Paint cel for just the background. If you want to use cel minimally you can paint your background art on cel and add your animation layer another way. I did this for this video. I did the line-work for the background in black ink on 4 sheets of 12f cel and then on parts I painted solid black, I scratched texture into. I then animated in paper over the clear backgrounds and then digitally colored and composited.
Illustration! It’s totally valid if you just want to test your cel skills on a single cel. One off cel illustrations let you go wild with detail in a way that you can’t really do with animation.
If you are hungry for more cel knowledge, I always like to suggest this this piece of history: Hannah Frank’s essay “The Multiplication of Traces: Xerographic Reproduction and One Hundred and One Dalmatians.”
General Tech Notes:
Scanners: Scanning your animation is easier, cheaper and takes up less space than using a down shooter or camera stand. You don’t need good lighting nor a nice camera nor capture software. I use an A4 ~$50 scanner from Staples for ALL my art. I have the lid removed and I use a stack of paper taped together as my “lid” to hold the artwork flat.
Peg bars/punching: I use a 1/4” round peg bar (you can make one using dowel and some hot glue) and a regular hole puncher (just get one with adjustable heads. This way you can avoid the headache of $700 acme hole punchers or sneaking into animation centres to punch paper.
Light tables: Led light pads used for tattoo artists are running about $20-30 online. Alternatives: glass tables with lights underneath, window on a sunny day, old computer monitors with white screen, bike light in a large Tupperware, get resourceful and creative with what’s around you!
This guide is designed for DIY animators and artists working non-commercially. Please use respectfully!
Make a practice of sharing knowledge with your peers and community if you have the resources.