scale model and red 2k 120

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EL_STUPIDO

Active member
hey all,

wow this cam thread gets more interesting every day. That still... I want to part with large sums of someone elses money that's for sure.

I have this great book on the history and technique of special FX which has a math equation in it to help you work out the frame rate to shoot a scale model. Most of the pros will know what I mean but for people stupid like me briefly: you shoot a scale model of a car at 24 fps and when you play it back it looks like a toy car. Shoot it at a higher frame rate and play the slo mo version of that back and suddenly the toy car has the right sort of gravity behind it. There's more to it than that of course but I want to be brief.

The equation is:

[Square Root of (D/d)] x 24 = FPS

where D = dimensions of full-scale object (in feet) & d = dimensions of model object (in feet). FPS = correct speed for filming.

The example the book uses is:

[Sqaure Root of (30/3)] x 24 = 76 FPS approx).

A truck 30 ft in length is represented by a model truck 3ft in length (1:10 scale minuture) needs to be shot at 76 fps to achieve the right Gravity.

So.... I am no good at maths at all. If the Red can shoot 120 FPS (max at 2k ] what scale minuture ratio would you build???

[square root of (D/d)] x 24 = 120 FPS

and what ratio would you have to build for 60 FPS

[square root of (D/d)] x 24 = 60 FPS

thanks for everyone's help. I really sucked at maths but I know someone will rise to the challenge.

El Stupido
 
according to your formula...

(D/d)=(FPS/24)^2,

So for 120 FPS the ratio would be 25. If you had a 30ft truck the size of the model would be 1.2 ft.

For 60 FPS the ratio would be 6.25. If you had a 30ft truck the size of the model would be 4.8 ft.

I knew algebra would come in handy someday.
 
Wow... that was quick... and good! Thankyou

so 1:25 for 120 fps & 1:6.25 for 60 fps

that'd be allright for doing scale model stuff then too then eh? this camera?

that's sick

El Stupido
 
update: just did some math myself... based on those scale ratios you still aint going to be shooting sweeping shots of Minas Tirith or the Death Star with this camera... even at 120 fps they would have to be pretty big bigatures... even for Peter Jackson!
 
yeah motion control sure is cool. Being able to repeat a camera move over and over... the mind boggles as does the wallet.

I still wonder what frame rate they used for those sweeping shots in lord of the rings, of say for instance 'the black gate' or minas tirith. I've seen the docos - they were minatures albeit large ones. Bigatures.

I am interested at what frame rate you'd have to shoot for a flashpot explosion to look massive.

However it's great to know that the Red can shoot scale model trucks and that kind of thing - a 1:10 scale and with the right lens, a bit of smoke it'll look convincing.

El Stupido
 
EL_STUPIDO said:
yeah motion control sure is cool. Being able to repeat a camera move over and over... the mind boggles as does the wallet.
Click to expand...
We're aiming to change that - Our system can be set up in less than a minute and is no more complicated than your web browser to operate. Cost is typically the big issue on moco products, ours is less than the cost of a Red camera body. :)

I can't wait to do some composite shots with our Red one.. its gonna be crazy.
 
Can't wait to see your MoCo system CVB - give General Lift a run for its money - please!!! Most of my MoCo experience is with the Milo, which is a *$@%^$% tank.

El_Stupido, keep in mind that calculating fps is only half the battle. The biggest hurdle with miniatures is faking the correct DOF of a full size prop (spaceship, car, etc.) This (along with detailing) is the largest reason for the trend towards bigatures (think Cameron and Independence Day, pre-Jackson). If you can't make really big miniatures, generally you have to pump a lot of light on your set to fake the deep DOF - on Alien 3 they reportedly melted models, black-wrap, and even barn doors because of the insane amount of light they used! For this reason a lot of MoCo miniature productions shoot at 3-6 fps to allow more light into the gate, and hence get a deeper DOF.
 
CVB said:
Lucky for me I have a motion control company :)
Click to expand...

Then you'll want to push, as I do, for easy connectivity of RED to your MOCO system... I'm hoping for both electronic/programmable (via USB) and physical (a literal "contact" connector) for shutter triggering.

Hopefully some thought by the RED team is given in this important area.

Regards,
 
Yeah, we're working on that Jim.. Our system is all TCP/IP and serial communication based and we'll have a full SDK for it as well. Jim J. said he's interested in third party integration so I'm sure it will be just a matter of time before we'll have stop frame animations and timelapse shots.
 
CVB said:
Jim J. said he's interested in third party integration so I'm sure it will be just a matter of time before we'll have stop frame animations and timelapse shots.
Click to expand...

Great, I'm hoping for sooner rather than later... I have to admit that usable timelapse and stop frame functionality is one of two deciding factors that pushed me over on buying the HVX.

With the RED, being able to tie into triggering an exposure and controlling shutter via signals is very important to all the guys wanting to put these things on MOCO rigs. Of course, we NEED great DOF at times, so slow shutter is a must, And with the extreme mobility that the small physical size gives (compared to, say, a Fries Mitchell convert), the RED will go gangbusters in this world.

You know, putting it a different way, anything I can do with my 90+ year old 35mm pin-registered B&H 2709 I want to be able to do with the RED...

Regards,
 
CVB just checked your site. Like the pic, wish we could see more about it and look forward to seeing it all when you're ready to show us.

Boothba that's great info re: mo control and frame rates down 3-4 and DOF. Yeah I know the DOF thing is difficult supposedly. I didn't know about aliens but I did watch the making ofs for T2 & ID4 which I found fascinating.

ES

Still reeling from the break in. The world is turning to sludge. What a damn shame.
 
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