30fps Compositing

Okay...so I need the real scoop about 30fps composting for digital post production.

When doing composites for commercials I always defer to the sfx people as to what frame rate they would like us to shoot and transfer.

Most of the time they say "24fps transfer is fine". in fact some prefer it.

I am coming in to a rather large job that wants to shoot all green screen (8 day job and the director wants to shoot a lot of high speed)

I know that computer composting can handle the 3/2 pull down effectively these days and pull good mattes, but the agency's sfx person has previously insisted on 30 transferred at 30.

What is the real deal. how can I convince them that it is a waste of money (and a compromise in look...i.e. the "sharper" motion you get with 30@30) to shoot for 30@30.

Isn't it possible (or at least relatively easy) to deal with 24@24 (NTSC that is) in compositing these days?

Thanks!

Dylan Macleod, csc
Toronto, Canada

www.dylanmacleod.com

Hi,

>isn't it possible (or at least relatively easy) to deal with 24@24 (NTSC >that is) in compositing these days?

Yes, it's just another thing to keep track of and render, which is probably why they don't want to do it.

Phil Rhodes
Video camera/edit
London

>"Yes, it's just another thing to keep track of and render, which is >probably why they don't want to do it."

Is this effort worth the thousands of extra dollars we will spend on shooting 20% more film stock. Remember...eight day job, 10-15 thousand feet of film a day...all in all about 100 thousand feet of film. At 30fps transfer this means we will shoot roughly 20 thousand more feet of film. about $1000 a roll here in Canada...$20,000 more (8 or 9 thousand pound for you folks in the UK) to a "help out the post guy"?

So if it is not the 3/2 pull down what is the hassle in post that makes 24fps so prohibitive? Hard drive space? Rendering time? Is that time and space more expensive these days than what I have mentioned above???

Thanks for the feedback!

Dylan Macleod, csc
Toronto, Canada

Dylan Macleod wrote :

>$20,000 more (8 or 9 thousand pound for you folks in the UK) to a "help >out the post guy"?

What makes you think it's simply to "help out a post guy?"

Maybe they like the smoother motion and less noticeable grain that comes with 30 fps shooting. Not to mention the minimizing of strobing in certain situations (car wheels, for instance).

Many, many commercials are and have been shot at 30 fps for years, particularly car commercials and other situations with fast motion. Less blur on green screen elements is just one item in a longer list.

Besides, what difference should it make to you what they want to shoot at unless you're paying for film and lab costs?

Mike Most
VFX Supervisor
IATSE Local 600
Los Angeles

>Maybe they like the smoother motion and less noticeable grain that >comes with 30fps shooting.

It depends who's saying it. If the director's come back from a meeting with the post people intent on shooting a rate, I wouldn't be arguing.

If it's someone else, should they be making that kind of decision?

Regards,

Phil Rhodes
Video camera/edit
London

>"What makes you think it's simply to "help out a post guy?" Maybe they >like the smoother motion and less noticeable grain that comes with 30 >fps shooting."

In this case there is no other reason to shoot 30fps other than a previous request from...ahem...the visual effects supervisor. We are not shooting cars...we are not shooting fast moving objects...

I am simply asking why?

Other than the creative reasons i.e. for sharp crisp imagery (also achievable other ways and a decision that should be made by the cinematographer and director)...what is the advantage?

>"Besides, what difference should it make to you what they want to shoot >at unless you're paying for film and lab costs?"

Kinda selfish attitude and highly impractical, especially in the current "budget crunch" climate.

I do about 40 days a year with this agency and director. money is always a concern. If I can save them 20k...that is a good thing (maybe we could buy the visual fx supervisor more hard drive space?)

So...is it just hard drive space and rendering time...seeing as motion blur isn't an issue?

Dylan Macleod, csc
Toronto, Canada

>30fps... I am simply asking why?

IMHO the most rational reason would be that they want a more immediate, realistic and even "video" look, as opposed to a more dramatic 24fps look.

Tim Sassoon
SFD Vfx & creative post
Santa Monica, CA

Hi,

>so...is it just hard drive space and rendering time...seeing as motion >blur isn't an issue?

Not quite. There's an issue that you would generally just want to unwind the 3:2 on the whole shoot, otherwise every time you make a cut you have to determine where in the pulldown you are. At least, that's how I've done it on the odd occasion I've had to deal with 3:2 material. If you choose to do this it means double storage and a (brief, probably faster-than-realtime) rendering process, unless the kit has a more elegant way to handle it with timecode and known A-frames - which an upscale house may well do.

So it's not MUCH of an imposition, but it does depend on specifics of the kit they're using.

Phil Rhodes
Video camera/edit
London

>it is only when the green screen appears that I hear "are we going to >transfer at30?"

Ah! But that doesn't mean *shoot* at 30fps, just transfer frame for frame. IMHO there's not much reason to do this - it's quite easy to remove the 3:2 pulldown, and speedups can confuse the editor. Just don't let the colorist do pick-up tape edits on the transfer master - having the cadence change without warning can be unhelpful.

Tim Sassoon
SFD Vfx & creative post
Santa Monica, CA 90405

>Ah! But that doesn't mean *shoot* at 30fps, just transfer frame for frame.

>Clarification...

No we didn't want to speed up the action. by suggesting we transfer at 30 we also shot at 30 (or 60 or 90 for slow motion effect).

...but our transfer base became 30

Dylan Macleod
Toronto, Canada

Dylan Macleod wrote :

>>so...is it just hard drive space and rendering time...seeing as motion >blur isn't an issue?

Motion blur in greenscreen or blue screen work is always an issue. The less blur, the better the detail retention in the matte - and any desired softness can always be added in post. That's one reason I always try to shoot objects at different distances from the camera separately in a green or blue screen situation. By shooting a reference with "proper" focus, then shooting the actual element in focus, a cleaner matte is possible and any softness can then be added back.

Since I'm not the effects supervisor on this one, I can only offer some educated guesses:

1/. The situation as described above (i.e., cleaner edges for more accurate matte extraction).

2/. The distinct, albeit somewhat remote, possibility that the green or blue screen work is going to be posted in a linear online editing bay, with the matte extractions done in "real time" by a hardware matting device such as a hardware Ultimatte, and compositing done via the matting device and a switcher, in a 30 frame video environment. This would be the only circumstance under which 3:2 removal might be a bit of an issue.

Not all compositing is done on computers, you know (although I
would guess that better than 90% is these days). I wouldn't imagine this is the case in a rather sophisticated market like Toronto, but one never knows.

3/. Your VFX supervisor is a bit "old school," and still believes in the things that were required in the past, when virtually all compositing was done in online bays. This is rare these days, but I have run into some film VFX supervisors who haven't worked in television recently and tend to think these old requirements still stand.

Mike Most
VFX Supervisor
IATSE Local 600
Los Angeles

>>Your VFX supervisor is a bit "old school,"

This is my hunch, that is why I am asking for advice from those in the know.

Thank you for the useful info.

Dylan Macleod, csc
Toronto, Canada

>>"Besides, what difference should it make to you what they want to shoot >at unless you're paying for film and lab costs?"

But - actually - I DO see it as part of my job to be fiscally responsible. Producers don't necessarily have sufficient technical knowledge to make accurate decisions about things like equipment, film stock, crew, etc. and I feel it is my job to help him/her with that with my knowledge.

In this case - an F/X guy is saying shoot 30fps and the D.P. knows this will cost more money in film stock, processing and telecine. As a D.P, I think he should be questioning 'why' because if a truly valid reason cannot be found and he is aware of this, why not inform the producers that there is money potentially being wasted. I say wasted, only if the F/X guy himself can't even provide a truly valid justification for it for THIS project, other than 'he's used to working at 30fps instead of 24fps' and doesn't really care if it costs the production more money.

If it truly goes beyond that and the F/X guy can demonstrate a valid reason why for quality or efficiencies sake 30fps is a better solution then - great!

Pardon the lengthy explain - but I wanted to cover some questions I anticipated being volleyed.

Roderick E. Stevens II
Director -o- Photography "just a squirrel, tryin' to catch a jumbo jack"
www.restevens.com
12on/12off

Roderick E. Stevens II wrote:

>>In this case - an F/X guy is saying shoot 30fps and the D.P. knows this >will cost more money in film stock, processing and telecine.

Telecine will cost exactly the same thing either way, because telecine charges are based on either running time or an hourly rate, not on footage or frame rate. The only difference in cost is in film and lab (i.e., stock and development).

Mike Most
VFX Supervisor
IATSE Local 600
Los Angeles

Mike Most wrote :

>>Telecine will cost exactly the same thing either way, because telecine >charges are based on either running time or an hourly rate, not on >footage or frame rate.

Yep - of course - I knew that when I typed it - but forgot to correct it. Thanks. You get the point though.

Roderick E. Stevens II (out of practice posting to email groups these days)
Director -o- Photography
12on/12off

- At the end of the day 30 @ 30 WILL only help in compositing and Roto situations. The eliminating of pulldowns will ultimately achieve possible superior mattes and keys. Which in the end will save the compositor time finessing mattes, painting edges feathering matte edges, removing pulldown frames, putting them back in etc. With that said, 24 fps compositing is getting to be the norm and a proper post producer should alot time for finessing in night sessions etc.

- When compositing CG into Motion picture, their really is no reason for it. Unless there are mattes to be pulled. It really is just MORE rendering time and framestore.

At the heart of the matter really, is if WE are shooting a spot that will rely heavily on post compositing and design and it will be the primary selling tool of the spot, then it is our responsibility to execute and respect that. I think sometimes production gets caught into thinking that anything is possible in post so to save their day and their overages they irresponsibly discount the fact that it will add to post time and post overages (POST has a budget to stick to too). Let me add that this isn’t the majority. Ultimately, the production company is getting paid, the crew (including the VFX supervisor) are getting paid to expose film that will handshake into post as smoothly as possible. The value of an extra day of compositing fussing around with stuff that wasn’t shot properly is wrong will certainly be equal to or more to the extra couple hours OT or extra film stock. (Dylan your 8 day shoot is an exception and smartly should be treat that way.)

YES, most anything can be done in post, but like in production with time and money. I am always considering the production and I would never sacrifice their day or monopolize time with silly requests. Although I cant imagine anyone arguing the fact that "they'll fix it in post" is probably the most commonly used term in modern day film production crunch time history. No one has ever heard a VFX supervisor say to an AD that they "don’t give a shit about the sun setting and your money shot, I need that green screen bracketed!!!"

Having said all this, being a VFX supervisor who also shoots frequently, I will say that I will never nor have I ever asked for something I didn’t need, or felt would be for the betterment of the project through all its stages. Really besides the agency it is only the VFX supervisor who sees the board from pre pro, into production then into online, but it is these questions that will bring the two elements closer and be better for everyone. Dylan, on the couple of occasions working with you, you’ve always shown me nothing but respect, and this shows why with your quest for knowledge and lack of production selfishness.

Chris Sargent

Chris Sargent wrote :

>>The eliminating of pulldowns will ultimately achieve possible superior >mattes and keys.

I'm sorry, but 3:2 pulldown is not now, and has not been for many years, any problem whatsoever. It is easily removed in any compositing program, usually automatically, and is simply a non-issue.

Now, if one were to say that exposing at a frame rate of 30 fps produces cleaner mattes because of less motion blur, THAT would be a reasonably accurate statement.

Mike Most
VFX Supervisor
IATSE Local 600
Los Angeles

>>In this case - an F/X guy is saying shoot 30fps and the D.P. knows this >will cost more money in film stock, processing and telecine.

Rod...you knocked it on the head.

I am really unsure of this Vfx supervisors skill. I have never questioned his request in the past but as Chris said, I believe it is valid in this case if it can save some money (which I will rapidly turn around and spend on fun toys like cranes and things...just kidding).

Hey Chris...thank you for the kind words.

I guess...in the end, I am trying to measure something in an absolute way. I know what 30@30 costs from my end. from reading the above responses I see that it is not quite as easy to quantify the costs 24@24 in post. that is...finessing mattes, painting edges, etc., are all different depending on the nature of the particular shots.

Thanks for the input and I'll let you know if we ultimately go 24 or 30...the suspense is killing me.

Dylan Macleod
Toronto, Canada

Dylan Macleod writes :

>> I am really unsure of this Vfx supervisors skill.

That's a horrible place to find yourself.

Sometimes they're just being safe or making their life easy and
sometimes, like the job I'm on at the moment, they really should get another job.

Happily the 24/30 issue is about the only one I don't come up against living in a 25 world!

Cheers

Geoff Boyle FBKS
Director of Photography
EU Based
www.cinematography.net

Sometimes they're just being safe or making their life easy and sometimes, like the job I'm on at the moment, they really should get another job...and every once in a while...very rarely, mind you, but every once in a long while, "they" are asking for something because they REALLY need it...

I make no absolutely no judgement about this situation, which I haven't really been following, but we sure do get a lot of, "Can't we just..." or "well on the last show, they said I could..."

This is where one has to start explaining the difference between rotoring a black glove and leather-jacketed arm off of a gray building and rotoring a head full of motion-blurred blonde fly-away hair off of a row of out of focus rose bushes.

Granted I spend most of my time working on stuff that will be projected - I can't hide between the scan lines of SD, but there ya go.

Mark "can you shoot it this way? Sure...but I won't be able to use it." Weingartner
LA based
VFX

>>Happily the 24/30 issue is about the only one I don't come up against >living in a 25 world!

I wondered why you Brits were keeping so quiet in this discussion!

Lucky you.

>>and every once in a while...very rarely, mind you, but every once in a long >while, "they" are asking for something because they REALLY need it...

Yes...I really am trying not to second guess here. I totally respect the needs of the Vfx supervisor.

My original post was trying to compare the cost of dealing with 24fps transferred at 24fps in post, versus the cost of shooting 20-25% more film stock by shooting and transferring at 30. On a job where you will shoot 10k-20k feet of film a day I thought it was reasonable to ask the producer to ask the Vfx guy why he needs 30@30.

Also factor in the idea that myself and the director actually don't want the look that 30@30 gives.

Dylan Macleod,csc
Toronto, Canada

For anyone who is still interested...

We shot 30fps and transferred 30fps (cha-ching!).

The irony is...the Vfx supervisor was not on set because...wait for it... they couldn't afford to bring him out!

As a result I was put to the test of having to shoot close to 100 product shots over the course of 10 days (on top of our regular schedule of shots with talent) and make all of the calls myself. glass bottle??? Okay, we'll shoot against white. mirror silver ring. macro shot...we'll shoot against black, etc.

My hunch about the invisible Vfx "supervisor" was confirmed when we found ourselves shooting locked off turntable shots...full rotations...and we'd be asked to shoot them rotating in both directions...oh boy.

Anyhow...glad to be working and the shoot was, despite all, fun!

Dylan Macleod, csc
Toronto, Canada

>>in the end he got everything he needed and cost the production at least >30k more as a result.

That may be so, but it also may have saved the project $50k or more in post roto work.

Back in the day (not so long ago), when there was one person who had overall responsibility for a project's budget from start to finish, it was always a consideration that not spending money in production would increase the post costs, more often than not by a lot more than the money saved while shooting.

Now it's almost always separate producers and budgets for production and post, and I can't tell you the number of times I've seen projects where production blew through the effects shots and left post with a steaming pile on their hands that cost a lot more to fix than anyone had anticipated.

Bob Kertesz
BlueScreen LLC

>>I've seen projects where production blew through the effects shots and >left post with a steaming pile on their hands

Just as bad are sets which just don't want to deal with VFX, and magnanimously leave us 15 minutes at the end of the day, when everything's being wrapped into the trucks, thinking that leaving no time or equipment's going to get it done faster. What happens is that VFX being a time-consuming PIA becomes a self-fulfilling prophesy.

I was on a movie last year where they built a beautiful bluescreen for us on scaffold across the whole width of the forecourt at the La Verne water treatment plant for a matte painting reverse looking out from the steps, then would only schedule the shots so late that the sun was on the other side, and it was basically too big to light. What's the point of throwing away all that rigging work? It ended up 100% roto.

Tim Sassoon
SFD Vfx & creative post
Santa Monica, CA

>>That may be so, but it also may have saved the project $50k or more in >post roto work.

Remember (read earlier post...started back in November) the debate was 24@24 versus 30@30.

Are you saying that if we shot 24@24 it would have cost an extra 50K in post roto work?

How so?

My other point is that it is important to have the Vfx supervisor on set so that s/he and I can discuss such things. weigh the pros and cons. I've often had Vfx supervisor say "don't worry I can take care of that easy enough" or conversely "no please give me a deeper stop so I can get a clean cut".

It was the absence of Vfx supervisor that cost the production money as well as (I still believe) they denied that all Vfx shots be shot and transferred at 30fps.

Dylan Macleod, csc
Toronto, Canada

>>That may be so, but it also may have saved the project $50k or more in >post roto work.
>>Remember (read earlier post...star [truncated, sorry]