Letterboxes Made Easy -- was 2.35 matte

[Ryan Collier <rcollier(at)postcentral.com>]

Here's an easy formula you can use for ANY PROJECT. (I'd underline,  
but no V8 yet.)

Matte = Original Vertical Picture Area - [(Horizontal Resolution) /  
((Aspect Ratio Sought) * (Pixel Ratio))]

As written:

Take the HORIZONTAL RESOLUTION of your picture and DIVIDE by [(ASPECT  
RATIO YOU ARE TRYING TO FIGURE) * (PIXEL RATIO)] this gives your NEW  
VERTICAL PICTURE AREA

Subtract the NEW VERTICAL PICTURE AREA from the ORIGINAL VERTICAL  
PICTURE AREA; this is your MATTE

Divide your MATTE by 2 and set your top and bottom crop accordingly.

For non-square pixels, the pixel ratio is (10/9)
For square pixels, the pixel ratio is 1 -- or 10/10 if you prefer :)

Works for any combination of aspect ratios and pixel ratios!!

Cheers,

Ryan Collier
Avid|DS Artist

~ The Past is Prologue ~

######################################################################## 
#########

Go on, try it!!

MATTE size for full-frame aspect 4/3, in a D1 project:

Matte = 486 - [(720) / ((4/3) * (10/9))]
Matte = 486 - [720 / (40/27)]
Matte = 486 - (720 / 1.48148148)
Matte = 486 - 486
Matte = 0
Duh.

MATTE size for 16/9 aspect, in a D1 project:

Matte = 486 - [(720) / ((16/9) * (10/9))]
Matte = 486 - [720 / (160/81)]
Matte = 486 - (720 / 1.9753086)
Matte = 486 - 364.5
Matte = 121.1 ≈ 121, set top and bottom to 105

MATTE size for 2.35/1 aspect, in an 1080i/59.94 project:

Matte = 1080 - [(1920) / ((2.35/1) * (10/10)] <--HD, so we use SQUARE  
PIXEL RATIO
Matte = 1080 - [1920 / (2.35/1)]
Matte = 1080 - (1920 / 2.35)
Matte = 1080 - 817
Matte = 263, set top to 130, bottom to 131

---
Subscribe? E-mail Majordomo(at)Softimage.COM with the following text in body: subscribe ds
Unsubscribe? E-Mail Majordomo(at)Softimage.COM with the following text in body: unsubscribe ds