CINEMASCOPE FORMAT

Cinemascope is not something exclusive to the Cinema, you can have this in your very own home.

This page has been setup to show you how it can be achieved and why you won't ever go back to 16:9 format again.

Be gone with those black bars forever! See www.anamorphiclens.com.au for more info.

In this section I will explain why Cinemascope screens are the better choice when choosing a screen format. 
The reason 16:9 screens are still being made and sold is because Projectors are native 16:9 panels (There are
also too many retailers who don't like change, but we won't go into that) When a Scope dvd comes out at your 
local Blockbuster store those dreaded Black Bars (grey bars) are put at the top and bottom to fill out the 16:9 shape. 
You cannot remove the black bars on a TV, which means the Cinemascope film, which is meant to be bigger and wider
is now smaller than the 6 o'clock news! You can however remove the black bars with a projector!

We can now emulate what is done at the cinema by using an Anamorphic Lens, like the Aussiemorphic MK3 lens 
and a Cinemascope screen. This is exactly how it's meant to be presented to us. Deluxe widescreen in all it's 
glory.

UNDERSTANDING CIH, It’s limiations and benefits.

SCREEN SIZE

The size of the screen is best found by dividing the room's length by 4.5. The actual number you use can be anything 
between 3.68 and 5.18 and where 4.5 is somewhere in the middle of that.
 
Dividing the room's length by the chosen number gives you an ideal screen height for that room that allows you to 
work out both Seating Distances and Throw Ratio. 

EG 1: Room length of 6000mm / 4.5 = Screen height of 1330mm (135 inch 2.37:1 screen)

If you want a larger screen than the math allows, then the best way to test this is to set the projector up at the back of
the room and measure the height of the light at the minimum zoom [smallest image size]. This is handy for also
checking the image height when an AT screen is to be used as these usually require the screen to be built out from
the wall.

ASPECT RATIO

The aspect ratio is simply the width in relation to the height to denote the shape of the screen. 35mm film
CinemaScope has an Aspect Ratio of 2.39:1 meaning the projected image is 2.39 times wide as it is high. As it turns
out, our Home Theatre equivalent is 2.37:1. This is because TV's evolution to wide screen has been based on 1.33x
steps where SD is 1.33, HD is 1.78:1 [1.33 x 1.33] and Scope is 1.78 x 1.33. The actual math requires the decimal
point to be taken to at least 7 places .

1.3333333 x 1.3333333 = 1.7777777 and 1.7777777 x 1.3333333 = 2.3703702.

EG 2: Screen Height of 1200mm x Aspect Ratio of 2.37 = Scope Screen Width of 2844mm

SEATING DISTANCES

With 1080 projectors, you can sit as close as 2x the image height but should not sit further back than 4x. These are
based on SMPTE recommendations and SMPTE's preferred distance is 3x the image height and the THX 36 degree
rule is 3.68x the image height.

EG 3:
Screen Height of 1330mm x 2.00 = 2660mm [closest seating distance]
Screen Height of 1330mm x 3.00 = 3990mm [SMPTE Preferred]
Screen Height of 1330mm x 3.68 = 4890mm [THX furthest seating distance]

Note that in the 6000mm deep room, this means that you are off the back wall, so allowing for Back Surround
speakers to be placed behind the seating location[s].

THROW RATIOS

The diagram shows that the beam angles become wider when using a Horizontal Expansion Anamorphic Lens.
To ensure the best results, the TR really needs to be as long as possible. We recommend a TR of not less than 2.0
[or greater] be used with the Aussiemorphic Lens MK3 for most HT projectors. There will be some cases that require
the projector to be mounted way further back than the calculated TR of 2.0:1 gives.

The easiest way to find the Throw Ratio and or Projector Mounting distance is to use the following math.

Scope Screen Width x 0.75 x TR [in this case 2.2 = distance of projectors lens from screen.

EG 4: Scope Screen Width of 2844mm x 0.75 x 2.2 = 4692mm which is a TR of just under 2.2:1. Again, this page
is an example and your individual projector may need to be mounted further back in order to reduce the
width of the light beam. If the projector can not be mounted back far enough, the screen height may need to
be reduced. Please see the following page for a visual explanation of vignetting.

Our showroom is 6 metres deep. The current screen is a 135 inch Scope screen - 1330 X 3156. This works out to dividing the room into 4.51 (6 / 4.51 = 1.330. So not far off the 4.5 formula. This really does work, try it yourself and see what sizes you come up with. This also works well for this room because I can have 2 rows of seats, one at 3.5 metres and the other at 4.9 metres from the screen. Contact us and we'll get that perfect screen size sorted out for you with no hassles.
8 to 9 out of every 10 blockbuster DVDS that you will hire or purchase are in Cinemascope format. Why then would you want to use a 16:9 screen to begin with? Unlike LCD and Plasma you can remove the black bars with a projection system. The result is a deluxe widescreen Scope image - The Way the Director Intended! Oz Theatre Screens can accommodate any cinemascope screen size up to 2.1 metres high and in some fabrics 2.5 metres high. For your own interest, we suggest you check out your video store's range of DVDS and have a look at the back covers. They will either state 2.35:1, 2.40:1, Anamorphic 16:9 or Letterbox 16:9. The Scope format was widened to 2.40:1 in the 1980’s to include both 2.35 and 2.40, but is in fact 2.39:1 at the Cinema and 2.37:1 on DVD for home theatre.	Check out the Aussiemorphic MK3 lens at www.anamorphiclens.com.au

Copyright © 2002-2009 Oz Theatre Screens. All rights reserved.

www.oztheatre.com.au www.ozts.com.au www.projectorscreens.com.au www.anamorphiclens.com.au