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Grgeon
10-16-2006, 04:00 AM
Hey Brian,

Hope it's ok to post this here in the EI forum. I've been familiar with your name since my old electricimage 2.9 days.

I currently work as an animator at scea. I'm looking to possibly attain a future position at a place like Persistance of Vision, Third Floor, Halon Entertainment, Pixel Liberation Front, Proof or even a big studio house doing previz.

Although my primary duties is animation and motion editing, i've done a bit of previz for some game cinematics. I'm wondering though what are some other skills i should try to attain to get a better footing in the previz biz.

The skills i'm looking to get into are:
compositing/shake
Digital Set Design modeling/texturing
Dynamics- particles- explosions, smoke, etc...
lighting/rendering
photogammetry
matte painting

What do you think? are some of these important things to learn to get into a fulltime previz position?

Thanks for being involved in the community, it's really great to get input by industry pros and not just wonder in the dark without guidance.

God Bless,
George

Vizfizz
10-16-2006, 07:22 AM
Hello George..

Well.. as you can imagine I have a lot I can say on this particular subject. Judging from your demo reels, I would say that you have sufficient experience to make the transition into previs. The biggest thing that you would need to focus on is your cinematic language skills. But lets take a look at your list:

1. Compositing/Shake - Minor requirement. Helpful, but most of the compositing skills you'll need for previs can be accomplished with After Effects. Nearly 98% of everything done in previs is accomplished in camera. Compositing is only required in specific situations.

2. Digital Sets - Obviously a strong polygonal modeling skillset is needed. The more tricks you know for improving your polygon skills the better. Combine that with a solid understanding of OpenGL and methods to improve hardware rendering and you're golden. Software rendering for previs is unusally reserved for the most expensive shots, or if there are technical requirements within the shot that hardware render buffer can not provide.

3. Dynamics - Minor Requirement. Some hard body dynamics can be valuable, but generally, its rare to take all the time to set up a dynamics pass within previs unless its absolutely critical.

4. Particles - Intermediate Requirement. You're much more likely to utilize particle systems within previs than dynamics. There's always a call for smoke, fire, sparks and explosions. However, remember, a lot of these can be aquired by using cards/billboards. In previs, everything is about speed.

5. Lighting/Rendering - Minor Requirement. Again.. focus on hardware lighting, the hardware render buffer, and any OpenGL tricks and texture baking techniques you can use to improve your scene's appearance.

6. Photogammetry - Minor Requirement. Could soon become a stronger requirement as more and more programs implement this kind of technology. Previs typically uses all different levels of detail into a scene and using this technique is a very solid way to get lots of detail in very low polys. Worth exploring.

7. Matte Painting - Minor Requirement. Just not enough call for it. Perhaps some skies and potential layered backgrounds could be used.. but usually that's going overboard.

------

If you want to become a previs artist focus on:

1. Camera Animation and cinematic language.
2. Camera Angles, Composition, and Continuity.
3. Low Rez Poly modeling and digital sets.
4. Low Rez Poly characters and rigging.
5. Understanding storytelling.
6. Editing and timing.
7. Non Linear Animation.
8. Tricks and cheats for improving speed and setup.
9. Animation vs VFX pipeline structures.
10. Integration for technical previs.
11. A solid understanding of various camera lens, camera backs, and aspect ratios.

A previs artist is: A Director, a Director of Photography, an Animator, a Modeler, a Rigger, an Editor, a Storyteller, an FX artist, a MoCap engineer, and so on. If anything, to become a previs artist, you must be ready to don any of these hats at anytime. However...ultimately, you'll have to decide if you wish to focus on conceptual previs or technical previs. Each focuses on different parts of the preproduction pipeline.

I could list a dozen more.. but if you focus on these.. you'll be much stronger.

Vizfizz
10-16-2006, 07:26 AM
Also visit this thread:

http://forums.cgsociety.org/showthread.php?t=318012&highlight=previs

Grgeon
10-16-2006, 05:33 PM
Yes! This is exactly the reply i was looking for. Thanks Brian. It definetely gives me a better sense of direction on where to focus my time.

That thread link and doc you posted is also a great read!

You mention cinematic language skills. I think i know what you mean, but could you elaborate just to make sure i'm on the right page here?

If it's what i'm thinking, it means i have to stop being lazy and finish reading the two books i got on visual story telling. Shot by Shot (http://www.amazon.com/Film-Directing-Shot-Visualizing-Productions/dp/0941188108/ref=pd_sxp_grid_i_0_1/002-5896085-7560035?ie=UTF8) and The Visual Story (http://www.amazon.com/Visual-Story-Seeing-Structure-Media/dp/0240804678/sr=8-1/qid=1161015920/ref=pd_bbs_sr_1/002-5896085-7560035?ie=UTF8)


Again thanks for the info and i hope to hang out here more often with you good ei folk :)

-George

Vizfizz
10-16-2006, 07:28 PM
George...

Spend as much time as you wish. We've got a good group here. :)

Ok.. I'm going to answer more of your questions from your private message to this forum for the benefit of everyone...so here we go:

- Is it nearly impossible to find a staff position as a previz artist?

Not impossible, but difficult. The reason for this is the transitory nature of our kind of work. We're jumping from one movie to the next and given the limited number of films that come out each year, there's only so much of the pie that can be divided amongst the companies you listed. That doesn't mean that the previs companies out there wont hire staff personnel.. its just that its very rare. We, like most of the large VFX companies out there, have adopted the "virtual workforce" method for staffing. POV has a dedicated talent pool that we draw from whenever we land a gig. This allows us to keep overhead low and we co-locate where needed. This also benefits the artists as that they can jump from one production to another production at their leasure. As previs becomes more and more the norm, greater consideration will be given to the previs process within the studios. This inturn, should generate higher previs budgets which will allow us to create a more dedicated facility. The problem with a dedicated facility/overhead however, is we have to factor that into our pricing.. and quite frankly, we don't like to do that to our clients. At POV we would rather:

1. Pay our artists more money.
2. Pass the savings onto our clients by hiring more experienced personnel.

- So what about security?

Being a freelance/contractor does require a different approach to handling your finances. However, our artists are always kept busy. I have several members of my talent pool who have been booked solid since last December. Of course we also reward loyalty. Those artists that work with us often are placed higher on the totem pole to be contacted the moment the next gig arrives.

- Is there a lot of down time in previz?

There are phases...yes. We're very similiar to the standard vfx industries, but we're usually operating 2 years in advance. We're working on films that wont be out until 2007 and 2008. There can be times when a month will slip by without work, but then there are other times when the work on a film goes on and on and on and we're begging for time off. As a freelance artist, you learn to anticipate these trends and plan accordingly. Personally, I love the time inbetween gigs because I can use it for a decent vacation. ;)

- How long does an average project last?

Very difficult to pinpoint. Typically an average project lasts between 6 to 10 weeks. That's usually for the smaller projects. Sometimes we'll land a gig that requires us to previs the entire film. If that happens, we can be on a project for 6 months. Thing is, projects usually evolve from one step to the next. You start by doing previs, then over time that turns into postviz and so forth. I was booked on one film that said, "we only need you 2 weeks"... that was last December. Its still going on today.

- Is it possible to stay employed throughout the year?

If you're good..you betcha. Like I said, I have artists that have been booked solid for months. Most have been migrating from project to project and they like that because the thrive on variety. I'm that way too. I don't like finals work. Who wants to work on a single shot for 2-3 months. Not me.

- When a project does come up, is it crunch mode till it's done?

We take good care of our people. Typical work weeks are 45-50 hrs. Anything past that is OT and we make sure the client realizes that. If you work..you're paid. There are times when crunch mode happens.. just like any other production...but we ensure you're paid for that time.

- What about insurance?

Subcontractors should take care of their own health and equipment insurance. You also handle your own taxes. We subcontract you, you inturn invoice us for your time and equipment rentals. I'm the supervisor and I coordinate all the freelancers for the project. I'm also usually the lead on the show. The best thing for you to do as an freelancer is to create your own dba. This also allows you to set your own rates with us because you are your own business. POV has to handle its own sets of insurances to cover you from injury and so forth while you're working with us on the premises of some studio or in our offices. Obviously, if our talent pool is taking care of their own health and equipment insurances, that helps keep our overhead low. In turn, we generally pay higher rates to our artists than our competitors.

- Can I work from home or use a laptop?

Working from home can sometimes happen, but usually the previs team is co-located with the director during pre-production. That could be at the studio or even remote overseas. Laptops are ok, but I usually recommend an additional larger screen for the director to see.

- Would Gnomon be beneficial?

Sure...I always recommend additional education. I'll be teaching another previs workshop online here at CG Talk in Dec. Check it out.

Brian

Grgeon
10-17-2006, 01:51 AM
wow! excellent Brian! Good call on putting this up publically in case others are in the same situation and had similar questions about this. This is very helpful information.

I'll re-read this when i get home. Very much appreciated.

-George

Vizfizz
11-14-2006, 08:29 AM
For those of you interested in previs, I am reoffering my online previs course here at CGTalk.

http://workshops.cgsociety.org/courses/000029/

The course and character rigs are setup in Maya, but the class info can be applied to any 3D application.

Grgeon
10-15-2007, 09:59 PM
Hey Brian,

It's been a long time since this thread started. 1 year to be exact. hehe. It was cool meeting and talking to you at siggraph.

I'm currently working at a game studio as a Cinematic Artist, doing a lot of motion editing and layout work.

I'm getting more into Layout and i had a question about cameras since it's pretty similar to previz. I was wondering about camera rigs and if you use them? Specifically camera rigs that simulate real world camera rigs, like a Crane, steady cam, dolly rig on tracks ?

Something similar to this: Hollywood Camera Works 3d dolly/crane rig pdf (http://www.hollywoodcamerawork.us/pdf/maya_dolly_instructions.pdf)

You feel these types of setups could make cg cams mimic real life camera moves in terms of limiting them to what they can do?

Or is it overkill if you just keep in mind what the camera is doing to make sure it matches real life like movements?

I'm also wondering if these are more for previz work that a real camera setup would have to match on a live action set and thus having that limitation of movement is needed to match say a crane shot like the examples PLF has on some of thier technical previz reels, where as what I do is for the cinematics of a game and will not have to be matched in the real world... if that makes sense. heh

Gonna have anymore Previz courses in the near future? i'm bummed i missed the last one.

Hope all is well.

-George

Vizfizz
10-15-2007, 10:31 PM
Hey George,

Good to hear from you again. So camera rigs eh? Well to answer your question, yes its not uncommon to create rig accurate cameras in your 3D application. There are literally dozens of custom rigs used out there and each has its own characteristics and dimensions. Normally we have a couple of things to consider when creating previs and layout for film.

1. Type of Camera & its camera back settings
2. Lens package
3. Camera rig

Now depending on the previs philosophy you're using (conceptual or techincal) you'll usually wind up worrying about a combination of these things. In conceptual previs, we're primarily concerned about the first two while in technical previs we'll add in the third.

As you can imagine, when you add in the limitations of an actual camera rig, it can inhibit the animator's speed and productivity. It can take time to realize that you're moving to fast, or rotating or traversing the camera out of various range limits. For example, on Stealth, our spider cam / libra head combo could only move on its cable system at 16 ft per second. Yet when animating cameras in maya, we commonly found that we were well exceeding that speed limit. That's what happens when you're dealing with fast moving jets. Specialized software was required to reevaluate the previs artist's camera moves and apply the excess camera movement speed to both the spider cam and the model (subject) that was riding on a specialized gimble. Thus we could virutally increase the perceived movement of the camera by multiple factors even though we never broke the 16 ft per second limitation. But if the previs artists had to animate their virtual cameras with everything like that in mind, we would have never finished.

I guess a lot depends on what you're trying to accomplish. If you have a very specific shooting environment that is space confined, and you know you're going to be using a very specific rig / crane / jib then by all means, it might be a good thing to create an animation rig with all these factors in mind. This way you'll know exactly what the DP can and can not do on set.

Since you're dealing with game cinematics which exist entirely in the virtual world, the need to mimic real world camera rigs is greatly reduced. Instead, you should focus on improving your technique and cinematography skills combined with accurate camera back settings and lens packages which will give you a more realistic look. Add in a couple of scripts to help manage camera shake and you should be good to go.

Grgeon
10-15-2007, 10:52 PM
Excellent! Thanks for the info Brian. Again, exactly the answers i was looking for and great examples too.

I think that last paragraph pretty much nailed it. Since it's staying all virtual, i should focus on those skills.

Question about lens packages... We didn't really have a set that we stuck with in this past project. Is this something that can increase the realism of cameras? Can you elaborate on that?


-George

Vizfizz
10-16-2007, 12:33 AM
Well.. in a virtual environment, you can use any lens length you want. There are no limitations. However in the real world, different lens have different optics and when combined with the type of cameras, produce different looks. If you were to stick to specific existing lens pacakge you would have to compose your shots with the limitations of the lens optics in mind...meaning...you may only a certain number of wide angle lens and only so many telephoto lens available to you.

Filmmakers and DPs understand those restrictions and compose shots within those limitations. Thus overtime you can start to predict what lens a particular director may choose over another in order to achieve a particular shot.

Virtual cameras don't have that limitation and you start to see silly lens values like say a 37.23454 mm lens. In the real world, that doesn't exist. Instead, you'd compose the shot using a 32, 35 or 40mm lens. Ultimately each lens length has a specific field of view and a good DP can tell the difference.

So.. if you want to make your virtual film look more like a real film, I'd say stick to the limitations of a real world film and the tools necessary to accomplish that task.

Grgeon
10-16-2007, 11:55 PM
Thanks again Brian. One more question if i may. When we talk about lens package, does that mean a set of lenses used throughout the film? ie. A movie has a set of 5-7 lenses it uses, like a 20mm, 35mm, 55mm, 75mm, and 100mm ? Or is it more just what you mentioned about not using arbitary virtual lenses like 32.453 ?

I'm thinking it's the former and that using a specific number of lenses and sticking to those few lenses in the virtual world could lend itself to a more cinematic cohesive feel, yes?

Thoughts?

-GC

Vizfizz
10-17-2007, 12:22 AM
DP's can use any array of lens depending on the type of camera used and the aspect ratio of the film being shot. There's also the option of shooting with spherical lenses or animorphic lenses. So, when its all said and done, a DP may have a specific lens package in mind.

For example. If you were shooting Super35 you have the option to crop to 1.778, 2.39 or leave it 1.33. Super35 is an intermediate film format...meaning super35 is never projected in the theaters, its used to transfer the captured image to a final format / aspect ratio for projection. Super35 is used because it has a greater film area to capture the images and you can avoid shooting animorphically for 2.39 aspect ratios. Super35 also has the advantage of using standard spherical lenses which are usually a little cheaper.

A typical lens package for Super35 may be Arri Zeiss Ultra Prime lenses which range from a 10mm to a 180mm. Here's some information and their field of view charts.

http://www.arri.com/prod/cam/ult_e.htm

Knowing this information now gives you the same restrictions for your virtual camera set up. You would set your camera ap to match a super35 camera and then you could compare the fields of view of the true glass optics against the field of view in your computer application. Generally I find that these values never completely match but they'll usually be within a few degrees of each other. Then you know for sure that what you're looking at in the computer will match what you would see in the real world provided that your world scale is the same. (or at least mathmatically equivalent) You can also restrict yourself to the same lens values as the Ultra Primes....thus you are starting to think like the DP.

Ultimately, these restrictions will cause you rethink your shots and their composition. Your viritual film starts to take on the characteristics of a film shot in the real world.

Grgeon
10-17-2007, 01:00 AM
great info. Thank you very much!

-GC

fangouw
01-16-2008, 07:14 PM
Thank you to George who brings up a previs topic into a discussion forum cus I've been looking around the internet about this sort of topic as I'm interested getting into the industry. And thank you to Brian who takes the time to write well-meated responses.

After what I've read from the thread I have a very good idea what skills are needed in becoming a previs artist. With the recent development of using game engine in previs such as Antics or Zviz, how does that effect previs industry and subsequently the artists.

Will the previs artist who has learned all of these 3d app skills (model, texture, esp. anim) can be cease to exist due to the expediacy result of the above programs?

Thank you for your time,

Fan Gouw

Vizfizz
01-17-2008, 03:19 PM
Fan,

Applications like Antics and zViz will not replace the need for a previs artist or the need for those artists to have traditional 3D animation skills. The very features that set these applications apart also have a tendency to limit them.

If all you are doing is conceptual previsualization then applications like these are very beneficial. They possess AI animation tools that can speed up the laborious tasks of key frame animation. But if you need to have a stronger link into an existing vfx pipeline, or if you need specific customization (which you almost always need), then knowing the "traditional" 3D tools is better.

For example: My teams are currently working on the next Star Trek film. We have very specific characters and creatures that must be integrated into the previs process. By the time we model and texture them in Maya, we just keep on going and rig them in Maya too. Getting these special characters into Antics or zViz is just another step that can potentially take more time. The process may be beneficial if you're doing a gig for ILM that uses zViz, but most likely your data will be going to other houses as well. Thus a industry standard file format, like a maya .ma/.mb file is the better choice.

BradKolacinski
03-08-2008, 12:54 AM
Fan,

Applications like Antics and zViz will not replace the need for a previs artist or the need for those artists to have traditional 3D animation skills. The very features that set these applications apart also have a tendency to limit them.

If all you are doing is conceptual previsualization then applications like these are very beneficial. They possess AI animation tools that can speed up the laborious tasks of key frame animation. But if you need to have a stronger link into an existing vfx pipeline, or if you need specific customization (which you almost always need), then knowing the "traditional" 3D tools is better.

For example: My teams are currently working on the next Star Trek film. We have very specific characters and creatures that must be integrated into the previs process. By the time we model and texture them in Maya, we just keep on going and rig them in Maya too. Getting these special characters into Antics or zViz is just another step that can potentially take more time. The process may be beneficial if you're doing a gig for ILM that uses zViz, but most likely your data will be going to other houses as well. Thus a industry standard file format, like a maya .ma/.mb file is the better choice.

Great thread Brian! I'm glad I found you on the CG Talk forums! Yes, I'd have to agree with you on this statement, that tools like Antics are not meant to replace those tools like Maya, Max, XSI, Lightwave, etc. but rather can provide an alternative solution for for rapid pre-viz or visualization. Antics will allow you to import custom assets using the 3DS Max Exporter plugin, and then animate them via point and click in real time, but as you've stated, if you're working in a VFX pipeline, you'll need to export that camera data and character action spline data. Antics also can now import .3ds and .fbx, with .skp coming soon. With Antics, the end output is a QuickTime or Avi file and is great for "throwaway" pre-viz, ie in many commercials, where the agency just needs to get sign-off from the client. Antics has many artists who've setup shop and are turning around 30 second commercials in 1-2 days such as www.viperpreviz.com (http://www.viperpreviz.com) or www.motionboards.net (http://www.motionboards.net)

Also, www.previz.com.au (http://www.previz.com.au)

Vizfizz
03-08-2008, 01:22 AM
Hey Brad...

Welcome aboard. We can always use more input on the subject of previs.

ammopreviz
04-01-2008, 12:49 PM
Hi Brain,
Just wondering if you have any information on the zViz.

I have some experience with Antics3d. I have a passion for previz as an alternative to my Flame/Smoke life.

I've got a little blog for Antics users which people might find interesting. www.antics3d.blogspot.com (http://www.antics3d.blogspot.com/)

Cheers from Australia
Tony
www.previz.com.au (http://www.previz.com.au/)
Youtube "ammoant"

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