Advice From a Mid-Level FX Artist: Part 2
Working With Assets
Learning to assess and work with assets that are published to the FX department is an extremely important skill as an FX artist. A lot of the time, you’ll have to start working on a shot before it reaches its final stage of development. This means working with temporary assets, or even incomplete ones.
- Working with incomplete animation is a challenge. If you are building an effect with animation that does not have any pre-roll , then the effect might not look correct. If this is the case, you can cease work (with permission from your supervisor or lead), and create a note notifying the correct people to add the pre-roll.
------------ Sometimes, animation isn’t properly aligned with the ground or camera. If this is the case, you will have to send the assets back to the animation department. If the collisions won’t work with the animation, then you won’t have a lot of luck making the simulation look correct.
---------- Point counts can also change on assets as well. This can cause a huge amount of issues when using animated objects for collisions. If this happens, you’ll have to create a section of your build to correct the issue. You can usually fix this problem by using point deforms.
-------- I also recommend checking for animation updates before you are told about them. The longer you work in VFX, the more it becomes obvious that communication between departments can become an unending game of telephone in the wrong circumstances. Sometimes updates can be made without other people being notified correctly.
----- Asset size matters. If something is too big or too small, it might be near to impossible to work with. You will need to assess how big everything imports as. You might have to rescale simulations later on if the asset you are working with is inconvenient. This in itself can pose issues. For example, if you were to create a pyro simulation, and then resize it 100 times larger, the resolution of the simulation would go down.
Part of being an intermediate artist is communicating with other departments and production when something goes wrong. When you need something fixed, you’ll need to explain it in a way that won’t get misconstrued, or miscommunicated. Sometimes, when you tell production what the issue is with a shot, they might not know which department to send that information to, or what exactly the problem is. It’s your job to tell them where and who the note should be delivered to (If they don't know), and to accurately describe the problem. Assume that everyone knows nothing, and explain the solution in the easiest terms possible.
Lidar and geometry scans can be tough to work with. They can have holes, uneven edges, and changing point counts. This often means you’ll have to re-mesh or retopologize the geometry. If you are working with a ground plane that is uneven or incomplete, you can ray a high-poly grid to the ground. The grid should grab the overall shape, but retain its amount of polygons.
First pass assets will probably not contain a lot of detail. If this is the case, they might only show the most basic shape of the object. You’ll need to make sure that your FX build can work with the asset when it reaches its final high detail stage.
Working With FX Builds
As a mid-level artist, you will most likely get more opportunities to build FX setups for productions you are assigned to. This means whatever you create, other artists will use. They can also potentially judge you on how well your setup is created.
Try to clean your setup as you progress through the scene. Everyone has the mindset to revisit the build after it is completed to clean it up. However, there might not always be time to do this with fast moving productions. It’s better to be ahead of schedule and fix any potentially confusing things before artists start using it.
Mid-level artists will also have more opportunities to work with leads. This means you have more chances to ask questions. Which is something you should do. Most FX leads have been in this industry for years. They have problem solving information that you probably do not possess, and information about the pipeline. Ask them as many questions as you can, but do not be overly annoying. Phrase the questions in a way that pertains to helping you stay out of their way. For example, let’s say you are working on a shot with a build that your lead designed. You notice that there has been an asset update, but the build now no longer works with the asset. You know that you need to fix this issue, and your lead is a bit busy. You can notify your lead about the problem, in case the build is being used in other shots. If you have the skill sets to fix the problem, you can get permission from your lead to modify the build, and then notify him and the team that the FX has been updated. If you do not have the skills to fix the problem, you can ask your lead about the best way to approach it.
I always like to view intermediate artists as assistants to the lead. Leads are busy people. Depending on the studio, they can be involved in bidding, dallies, and shot sequence meetings. As well as show onboarding, tutorial and documentation creation, build creation, and assistance to junior artists. As an intermediate artist, tasks might be handed down to you that the lead might be too busy to complete. These tasks are amazing challenges to create something impressive for your Showreel.
------ Document everything you are using for the shots. Creating show documentation is critical for artist workflows. If you work in a larger company, or in one where artists get frequently moved around on shows, problems can quickly become overlooked, forgotten about , or mishandled. The same goes for FX builds, and shots.
By documenting something, you can just hand that information off to the next person who joins the show. This allows for less time to be lost when it comes to onboarding artists, and assigning them new work. Documentation also works as a great instruction manual for junior artists who are not sure what they should be doing. It should show them the file paths to builds, pictures of important nodes, problems that they might encounter, the solutions to those problems, and publishing information.
Make sure that everyone on your team knows where the documentation is. If not, you could possibly have multiple artists creating different builds for the same effects. Which can lead to supervisors becoming confused, and a lack of consistency between shots.
Production often doesn’t understand the length of time it takes to build something in FX. Usually, most shots cannot be completed in two days, even if they are scheduled that way in Shotgrid. If you are placed in this situation, let production know. The least they can do is plan for any scheduling adjustments.
Farm management is extremely important for meeting your deadlines as an artist. If you don’t know how to manage your renders well on a farm, you could also potentially cost a studio more money than it needs to.
When working with a render farm, it is important to remember that high priority shows will have the most access and blades on the farm, versus a show that does not. If you are not working on a high priority show at your studio, you’ll have to factor in the farm wait time before you tell production when you’ll be submitting a version of the shot.
It’s not unheard of to have the farm delay a version that you would like to submit the day of. So as an artist, you’ll need to create a system for yourself that can work around these wait times.
From personal experience, I always find that render farms are usually the fastest during the morning hours of the day. This is because, everyone is still accessing their renders from the previous night, submitting their rendered work, and accessing the day’s tasks. I find if you can get at least your caches completed on the farm the night before, you can easily plan for rendering the next day. Even better, if you can get your renders the night before, you can have increased safety that if they do not turn out ok, you can re-render the next morning.
--- Sometimes, renders can take unusually long per frame. This probably means that something has gone wrong. If you are not rendering something super heavy, high-res, or close to the camera, rendering one frame should not take over an hour. Make sure your simulation is optimized correctly, the caches are looking correct, and the render settings are optimized as well.
--- Always make sure you are communicating to production when you need something boosted. Do not do it yourself. This will slow everyone in your department down, and will not make you any friends.
--- Double check with your lead if you really need to render something to show to the supervisors. Sometimes it’s better and faster to upload a flipbook of your shot if you are able to do so. Assess to see if what you are creating needs to be showcased with shaders and light rigs, or can be shown on its own.
Rendering anything that is a volume is most likely a good idea. However, you will need to be careful as sometimes your renders can be deceptive. There are tools in Houdini, such as the Pyro Bake Volume SOP that allow you to adjust the look of your density post simulation. These density changes show up in the render, but are not applied to the volume itself. If you need to export the raw volume to lighting, you’ll need to remember the setting you changed on this node, and apply them to your volume’s density.
I like doing this with a volume wrangle, and this expression:
f@density *= chf(“multi”);
Some studios have tools for wedging. Wedging is a fancy way of submitting all your caches and renders to a farm at once, and allowing the farm to write them to disk in the order that they were connected in the node tree. Every studio has a different way of doing this, but I recommend using this farm submitting tool as much as possible. This saves you time, verses submitting your caches one by one. It also helps you solve problems. If one cache fails in your node tree, then you know where the problem is located. Which will be right between the cache that failed, and the cache that did not.
Wedging is also great, and confusing for large setups. It’s often daunting to replicate a large setup per shot, or even create one. Plus, the more complicated an emitter or collision object is, the heavier it will be as well. This means, you’ll need to place caches in strategic areas. You do not want to create one cache that has to playback the emitter, collision objects, and the simulation before it saves it to disk. This will cause the cache to take up a massive amount of storage space. Plus, it will take longer on the farm.
The more caches you have in a node tree, the more confusing it may become to set them up for a wedging system. You need to add them in the correct order as you create them, otherwise good luck trying to remember the order of everything.
If something is continuing to fail on the farm, there is something probably wrong with the setup itself. No matter how you retry the simulation, render, or cache it will always fail. Before submitting remember to check these things:
- Make sure your caches have saved out the correct frame length of the shot.
- If you are submitting a render, make sure your camera is correct, you have selected only the objects you would like to render. As well as double checking that you have attached materials, and added lights to the scene.
- Playback your caches to make sure nothing is exploding before you render it.
- Make sure no other SOPS are erroring out when you play back the simulation or animation.
- Check how much memory the cache is taking up. If it is super heavy it may not render.
- Check to make sure your mattes and holdouts are correct.
- Check your collision objects.
If you want your work to be approved quickly, you have to present it in a manner that is appealing to the supervisor. You also have to make sure that whatever you submit is easy to understand.
Here is an example checklist for submitting renders:
-- Mattes and holdouts: Does the scene need them?
-- Distortion maps: Do any need to be applied to the slap comp for the FX to align properly?
-- Playback the Scene: Are any of the FX glitchy? Have the renders come off the farm correctly?
-- Plates: Are you using the latest one? Does the FX correctly align with the animation? If not, why?
-- Rotos: Does the scene need them?
-- Notes: Leave more than a vague description when submitting your shot for review. The note should address any previous concerns the supervisor had about the previous version.
-- Color Correction: Don’t do it. When you slap comp your work together, do not change the color or hue of the render in your nuke script. At the most you can adjust the brightness level. If you change the color of your render, this will cause a lot of confusion in the compositing department. They may not have access to your file to see the changes that you made, and might be extremely confused when they see the render coming out of the lighting department.
-- Contact Sheets: If you have built an effect that is created from layers of particles, or multiple simulations, you will need to create a contact sheet. This will better explain to the supervisor what exactly the effect is.
Supervisors can send something back just because they want to. They have that power, and you have to respect it. So it’s best to ask them what they want to see. Here are some tips for keeping your scene clean, and appealing:
-- Foresight: Will the effects blend into the next and previous shot? Double check. If you don’t, the supervisor will.
-- What’s Different?: If you are submitting work, ask yourself: What makes this version different? Does it look similar to the previous version? If so, you probably need to re-read your supervisor's notes.
-- What’s The Focus of The Shot?: Make sure your effects are not concealing any character’s faces, are overly dense, or distract from the main purpose of the shot. FX can help make CGI characters blend into live action elements. It can also make a shot look overly convoluted.
-- Don’t Feel Embarrassed: Sometimes artists can feel exhausted, embarrassed, or not not proud of their work. These feelings are normal. However, do not let them stop you from reviewing your renders. If you can catch a mistake before your supervisor does, you’ll save everyone's time. That’s nothing to be embarrassed about.
-- When in Doubt: Ask the supervisor. They will tell you how the FX should flow across the scene, whether they need to see contact sheets, provide you with any reference, and further feedback.
In this stage of the pipeline, things can go wrong very fast. When you publish something, you have to be aware of how other departments will be using your FX, as well as how the publishing system at your studio works. Every studio has a different system.
You also have to make sure that you will be publishing the required attributes along with the required FX. If there is a documented way to publish something for your department or show, check it before publishing. You might be missing something. If you are, you will more than likely have to republish when someone else notices the problem.
Most of your publishes as an FX artist will go directly to the lighting department. It’s a smart idea to team up with lighting, and work with them to document problems. As well as the solutions to those problems.
When lighting and FX communicate, great things happen. Publishes can be rendered without issues, alignment issues in shots can be found more easily, and pipeline issues can be caught before they become massive problems. The other great aspect of communicating with lighting is that both you and the lighting artist benefit. Part of being a well rounded artist is learning what other departments do. You can never become a great supervisor if you only know how one department works. If your career goal is to end up as a supervisor, you need to understand what happens to your work at different stages of the pipeline.
If a published effect continues to fail on the farm, do not ignore it. If the farm cannot handle it, neither can the lighting artist. Check to make sure the Alembic or VDB you are attempting to publish does not have any major issues.
Remember that lighting artists are most likely using a different software to render everything. Houdini can be used for lighting. However not every studio uses it for that purpose. Pipelines are made to make sure that anything being imported and exported from different softwares can be properly handled. However, sometimes things can go wrong.
-- Delete any attributes that other departments will not need in your FX.
-- Keep your velocity, id, and path attributes. ALWAYS.
-- Check to make sure the approved effect does not error out for any frame in the length of the shot.
-- Check with the lighting and compositing department to see if you need to render, or publish any extra attributes or passes with your FX.
-- Document any occurring problems. Then share that information with your team.
-- Add notes to specify if this publish is for temp, or for final. Helping specify which animation publish you used to create this effect also helps.
-- Never save over an old published file.
-- Remember to version up your publishes.
That’s all for now folks!