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class="Paragraph" Miniature Formula

Published : 7th March 2004


Someone asked for the miniature formula recently but unfortunately I deleted the post.

Here's what I found from research and the very helpful responses I received from the CML. (Many thanks...)

The formula is as follows : 24 x square root /D/d = fps

What this all means is that the frame rate for a scaled miniature is found by taking the square root of the scale size D/d and multiplying that by 24. I recently worked in 1/48 scale and the frame rate ended up being 166fps.

This was found by 24 x square root of 48/1 = fps
or 24 x 6.9 = 166fps

I hope this makes some semblance of sense.

But the best thing to do is test, test and test because it all depends on what you're shooting in regards to speed of the action and content.

Jim Sofranko
NY/DP



Jim Sofranko writes :

>The formula is as follows : 24 x square root /D/d = fps

My God! that makes it complicated

Normal speed multiplied by the square root of the scale of the model is it in English

Works every time.

Cheers

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



>Normal speed multiplied by the square root of the scale of the model is >it in English

There's a reciprocal in there somewhere, isn't there? Square root of the reciprocal of the scale times normal film speed?

Art Adams, DP
Mountain View, California - "Silicon Valley"
http://www.artadams.net/



Art Adams writes :

>There's a reciprocal in there somewhere, isn't there? Square root of the >reciprocal of the scale times normal film speed?

Picky, Picky, Picky

OK, scale is 36:1 or 1/36th then you run at 6 * normal.

Just run at the square root of the biggest number in the scale.

Cheers

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



Geoff Boyle wrote :

>Picky, Picky, Picky
>OK, scale is 36:1 or 1/36th then you run at 6 * normal


Well, the square root, 6, of the biggest number, 36, multiplied by 24, sooooo it's 144fps. It took me a few attempts with the language and math to realize it is much simpler than it appears.

Reciprocal, we don't need no stinkin' reciprocal. I took 4 years of Math in high school...math 1. Over and over again.

Jim Sofranko
NY/DP



>Reciprocal, we don't need no stinkin' reciprocal. I took 4 years of Math in >high school...math 1. Over and over again.

We deal with them all the time, Jim...Reciprocity Law.

Double the light, halve the exposure, triple light, exposure is
1/3.

Now the reason it doesn't work directly with f/stops is they are function of Pi. I'll take Apple, please.

Happy New Year, All,
Don Canfield