This is topic 3-D Aspect Ratio in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.


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Posted by Michael Coate (Member # 757) on 02-27-2005, 02:15 AM:
 
Question about the aspect ratio of "over/under" 3-D formats used during the 1980s (StereoVision, ArriVision, Marks-III Depix, etc.).

What is the intended projection aspect ratio? Is there an SMPTE spec? Is it 2.35:1? 2.39:1? Other?

Anyone have the BKSTS wall charts? I believe one of them included some frame samples from over/under 3-D and may have listed the aperture dimensions. If anyone has these posters, will you please post the aperture dimensions here?
 

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Posted by Stephen Furley (Member # 1277) on 02-27-2005, 03:25 AM:
 
I don't have the wallcharts here, but they do show various examples; I can't remember if they give dimensions.

The examples shown clearly varied in size, and I don't think there were any standards, it varied from one equipment manufacturer to another, and from film to film.
 

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Posted by Hugh McCullough (Member # 1542) on 02-27-2005, 04:37 AM:
 
According to my copy of the BKSTS wall chart the ratio for left over right 3D was 2.35:1
 

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Posted by Pete Lawrence (Member # 130) on 02-27-2005, 07:54 AM:
 
Here is a scan from Starchaser. Got your calipers?

The Paramount mirror box instructions states use their aperture plates or none at all and mask the spillage on the port. How was their plate different?
 

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Posted by Mark Lensenmayer (Member # 134) on 02-27-2005, 08:53 AM:
 
I have a document from Stereovision International dated 1983 "Principles of Quality 3D Motion Picture Projection" that mentions 2.35 throughout.
 

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Posted by Gordon McLeod (Member # 33) on 02-27-2005, 10:15 AM:
 
Each film had its own standard as the division septum was different from camera lens system to system as was the optical centerline
each film had its own alignment film with corner marks for the masking to be brought into
 

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Posted by Darryl Spicer (Member # 711) on 02-27-2005, 12:41 PM:
 
I do know that when Friday the 13th part 3 played at the local drive-in it was showen in cinemascope. So I am assuming that the 2.35 was the intended ratio.
 

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Posted by Jeffry L. Johnson (Member # 453) on 02-27-2005, 03:27 PM:
 
"Principles of Quality 3D Motion Picture Projection" by Chris Condon,
©1983, StereoVision International, Inc.:

3-D FILM INFORMATION SHEET
(For choosing the correct lens setting)

The STEREOFLEX "HI-LITE"(tm) and STEREOSTAR(tm) adjustable 3-D
projection units will project all of the following films. (Contact us
for matching alignment test films.) Compact STEREOVISION(tm) split
barrel non-adjustable 3-D lenses can also be supplied for _any_ of these
films. Please specify.

35mm 3-D RELEASE PRINTS
ABOVE/BELOW TYPES

ALIGNMENT FILM OPTICAL CENTER SPACING
A/B TYPE .359
"The 3-D Movie" *in production June 1983

A/B TYPE .366
"Jaws 3-D"
"Amityville 3-D" *in production June 1983

A/B TYPE .370-.375
"Comin' At Ya"

A/B TYPE .374
(SAME AS STEREOVISION WIDE SCREEN)
"Swordkill" *in production June 1983
"Hot Heir" *in production June 1983
"Metalstorm" *in production June 1983
"Parasite"
"Rottweiler"
"Revenge of the 13" (Shogun Maidens)
"The Winners" (short)
"Magnificent Guardsmen"
"Emanuelle-4" *in production June 1983
"3-D on Parade" (short)
"Dynasty"
"Wild Ride" (short)
"Hit the Road Running" *in production June 1983
"Rah Rah You're Dead" *in production June 1983
"Pensionatte"
"99 Women" *in production June 1983
"Tales of the Third Dimension" *in production June 1983
"Return of the Living Dead" *in production June 1983
"The Legend of Venus" *in production June 1983
"Dark Zone" *in production June 1983

A/B TYPE .380
"Warhol's Frankenstein"
"Fantastic Invasion" (The Bubble)
"Attack of the Giant Gorilla" (A*P*E)
"Artigato"
"Rock and Roll Hotel" *in production June 1983

A/B TYPE .383
"Love in 3-D"
"Tickled Pink" (What the Butler Saw)
"North and South Chivalry"

A/B TYPE .387
"Spacehunter"
"The Man Who Wasn't There" (Under Pressure) *in production June 1983
"Prison Girls"
"Friday the 13th--Part III"
"Treasure of the Four Crowns"

A/B TYPE .404
"Tiger Man"

CONTACT STEREOVISION INTERNATIONAL, INC. FOR ALIGHMENT LOOPS FOR ANY OF
THE ABOVE FILMS. $10.00 EACH WITH CONTAINER. 100 ft. LENGTHS $35.00
(ON PLASTIC CORE).
 

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Posted by Gordon McLeod (Member # 33) on 02-27-2005, 10:51 PM:
 
Daryl said "I do know that when Friday the 13th part 3 played at the local drive-in it was showen in cinemascope. So I am assuming that the 2.35 was the intended ratio."
the 3d prints were about 2.5:1 with the width of the marks stereo septum
 

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Posted by Frank Angel (Member # 248) on 02-28-2005, 07:09 AM:
 
I understand that the septum might vary, but why would the centerline?
 

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Posted by John Pytlak (Member # 331) on 02-28-2005, 10:18 AM:
 
Standard SMPTE 257-1998 "Stereoscopic Prints with
Vertically Positioned Subframes —
Projectable Image Areas" says:

quote:

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1 Scope
This standard specifies the maximum dimensions of
the film image area intended for projection from a
35-mm motion-picture film using vertically positioned
subframes for stereoscopic projection, and the placement
of this area relative to the perforations and the
reference edge of the film.

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