How to put VFX and animation into your film ~ Digitopia Film Blog

I've been asked so often how to integrate VFX and CG into film by low and no budget filmmakers. I've written a quick guide on how you can put in VFX and CG into your movie, whatever budget you are working at this process will work for you.

Follow this simple process

i. Find out who you need to do the job

ii. Define and gather reference

iii. Previz

iv. Visual Target

v. Integrate into the backplate

Stepping through these one at a time we’ll drill down to the core of how you can get your animation integrated into your film on time and on budget

i. Find out who you actually need to do the job

This is quite important thing to understand at the start, the range of different jobs involved in bringing a visual effect or particular animation to life is quite intense. I speak about it in great detail in my book ‘VFX and CG Survival Guide for Producers and Filmmakers’ going through what each job role does and how the dependencies between different artists work. Here for the sake of brevity I’ll give you the bare bones of what you need to know.

If you want a character to animate

You are going to primarily be looking for an animator.

The animator needs some support people or materials, i.e. he/she (I’m going to dispense with the ‘he/she’ construct from hereon) will need

- a model and

- a control rig to animate.

Fig 1. An animator needs a model and a rig before she can start the animation

The model is what you expect it to be, i.e. a model of a robot, mule or a spaceship. Depending upon how you progress you may either purchase a model on one of the many online repositories or if you can’t find one that suits your needs you may need to hire a modeller to build one.

Fig 2. Turbo Squid is one of the many online repositories of CG models that you can buy

Once the model is made it cannot be animated until control rig is applied to it. Some of the models you buy online may come with a control rig attached others won’t, be careful to check that you have what you need when you purchase the model, ideally get the animator to specify which one they need and whether they need to buy anything else for it, i.e. a control rig, a set of textures etc.

It is quite possible that you could get an animator to do all the modelling and rigging herself but ideally you’d want her to focus on the animation as that is what you are hiring her for. Either find a model and rig or hire separate people to model and rig the character. Asking the animator to find any support people that she needs is a sensible idea, as she has probably worked with modellers and riggers before and can explain exactly what she needs from them.

If you want VFX such as an explosion, water, smoke etc.

Here you are going to need an FX artist, an FX artist is completely different from an animator, he spends his time tweaking variables in a simulation to create the perfect dust storm or magical effect. The effect artist can work more independently as he doesn’t need such a wide range of support people and often effects artists are attune to shader writing, lighting and compositing (see below).

Fig 3. The effects artist will control simulation paramters to create any manner of natural phenomena

Houdini Fur test 02 from Farhan Qureshi on Vimeo.

Houdini Fur test 02 from Farhan Qureshi on Vimeo.

Video 1. FX can range from complex fluid simulations to hair and fur simulations

Do you need a separate lighter?

The lighter is someone whose job it is to take the animation light and render it into its final state. This is the person who may write the shader for the final CG. A shader is a set of instructions that the renderer needs to know about, i.e. is it shinny or dull, does it have sharp specular highlights or large glossy ones, how does it reflect and absorb light, i.e. a shader will contain a complete list of instructions.

Fig 4. A lighter may be able to write his own shaders that will achieve the look you want

Ideally you want an animator to be focussed on providing a great performance for you character not to have her attention split between lighting and rendering which requires a complete mind shift and different skill set entirely. Conversely FX artists are expected to light and render the work themselves, in part that the disciplines are closer aligned and the lighting considerations for FX would be quite different than the rest of the CG pipeline.

Do you need a separate compositor?

Really you do, as the compositor is another stage removed from the work either an animator, FX artist and even a lighter do. In part this is due to the fact that the compositor works in the 2D realm. It is quite possible that you’ll have your FX artist light and composite the shot. This really depends on the budget you have, which we are assuming for the purpose of this blog post is quite low. Ideally if you can get a separate compositor than it will free your other CG artists to focus on what they do best, i.e. animate, do fluid simulations, light etc.

Fig 5. A compositor would put together all the separate elements together in the final shot

ii. Define and gather reference

It’s actually quite startling that the first item is missed out by so many filmmakers when they engage a VFX/CG artist or Animator (although they are three different disciplines from hereon I’m going to use VFX, CG artists and animator interchangeably just to avoid the clumsy VFX/CG artist or Animator construct) is to not be specific in saying what they want.

If you want butterflies in your shot, then don’t just say ‘I want so butterflies in the shot’ as that can be interpreted in so many different ways. Instead be specific and say I want

- 100 butterflies in the shot

- I want them to have a wingspan of between two and three inches

- I want them to be shocking pink, bright yellow and deep purple in about equal ratios

- I want them to fly across the screen in a linear manner going from point A to B in 3 seconds

- Here is some photo and video reference of the type of motion and colours I want

- I need them in three shots by the end of the month

Do you see how this is much more specific? You as a filmmaker are now much more likely to get what you need in the timeframe that you asked for. I can’t understate how important it is to spend twenty minutes up front writing a detailed description of what you need think in terms of

- scale i.e. the need to be one fifth the screen height,

- velocity (remember from high school physics class, velocity is different to speed, velocity has a direction associated with it, i.e. I want them to move 5 meters per second from the green lamp towards the red potted plant)

- dig up reference, if you don’t have time to trawl youTube or Vimeo for reference ask the animator to dig up reference for you, she is more likely to have a repository of FX reference

- get storyboarding, this doesn’t mean that you need to hire a storyboard artist, you can jot down the basic shapes and forms that you want to happen with particular reference to the scale and velocity you want.

iii. Previz

There’s a tendency for artists to always want to present their best work. This is true of anyone but I have found with artists and animators that this tendency is taken to the extreme. The problem that you face as a filmmaker on a limited budget is that you can’t afford an animator to go off for three weeks to do a perfectly good animation that you didn’t ask for or doesn’t fit your movie.

The solution to this is Previz. Previz is short for pre-visualisation. In its current form it means that you do a rough version of the animation for blocking purposes. In truth previz is a relatively new term for an older term called blocking, except that previz today has taken on a separate discipline and identity. You don’t need to take it this far, but make sure you get the animator to do some previz so that you can quickly establish the timings and movements – be sure to state that you understand that it is blocking/previz and that you’re looking to establish the movements and timings and not expecting anything final.

Video 2. Doing Previz up front can help you determine the flow of the animation earlier and make changes faster before too much work has gone into the animation.

Getting this step done and signing off on it will mean that you will get what you want sooner otherwise wait for the three week deadline to pass before finding out that what you get isn’t what you asked for.

iv. Visual Target

By now you should have signed off the previz and can focus on the aesthetics of how the effect is lit, how the textures look and how well it renders. This is one of the important lessons that I’ve learned working in games, is to first do the previz and then aim for a visual target so that you don’t get distracted along the way. It will help the artist that you hired too to separate the animation and the lighting tasks.
If you have multiple shots then ask the artist to take one shot through the whole pipeline first (i.e. from reference -> previz -> visual target), you’ll find that you only need to do the visual target once and when the lighting and rendering parameters are established you don’t necessarily need to revisit them. It’s just a case of importing the light rig (which you should sign off on your first sample shot) noting how long the renders take. Multiply how long the renders take with the number of frames you need rendered (i.e. the number of shots multiplied by the shot duration) and you will know when you should have the shots returned to you.

v. Integrate into the backplate

Once all the effects are done you will need them composited onto the backplate which you provided. Compositing is normally done by a separate person known as a compositor who has quite a different skill set to an artist or animator. That is not to say that an artist or animator couldn’t do it, but they wouldn’t be able to have it fit in to the backplate as well as a compositor would be able to.

If you are having an effect which gives off light, like an explosion, bear in mind that for the budget you have the CG explosion may not be able to scatter light onto your backplate in the way it would if it was filmed practically. If you have CG water simulated then again bear in mind that you may not get proper caustics or reflections between the CG water and the filmed backplate. This is where you may want to hire a compositor as their skillset is better suited to find solutions and workarounds based on the VFX you asked for and the backplate that you provide.

This and many other things that you need to know on how to get VFX, CG, animation etc. into your film can be found in my book ‘VFX and CG Survival Guide for Producers and Filmmakers’.

It is the first book on VFX and CG that looks at how all the various parts of the pipeline fit together from your point of view and tells you what you need to know and provide to any artists that you may work with.

The book is available as both an ebook on your Kindle (you can download kindle reading apps for your tablets and smartphones, web browsers or PC and Mac) and as print book from these links below.