[comp.graphics] synthetic -> hologram

rick@hanauma (Richard Ottolini) (08/24/89)

Plate #22 in Upstill's RenderMan companions is the "shattered globe" image
that recently appeared as a National Geographic cover hologram.
Could someone explain how this synthetic image was converted into a hologram?
Thanks.

chuck@melmac.harris-atd.com (Chuck Musciano) (08/24/89)

In article <4791@portia.Stanford.EDU> rick@hanauma (Richard Ottolini) writes:
>
>Plate #22 in Upstill's RenderMan companions is the "shattered globe" image
>that recently appeared as a National Geographic cover hologram.
>Could someone explain how this synthetic image was converted into a hologram?
>Thanks.

     As I recall, that is not a synthetic image.  According to the article in
the Geographic, they set up the standard holographic photograph stuff
(reference laser, image laser, I'm sort of fuzzy on this stuff) and an
elaborate trip mechanism to fire the camera (or whatever) as a ball bearing
was fired through a real crystal globe.  They had some neat pictures of the
whole setup.

Chuck Musciano				ARPA  : chuck@trantor.harris-atd.com
Harris Corporation 			Usenet: ...!uunet!x102a!trantor!chuck
PO Box 37, MS 3A/1912			AT&T  : (407) 727-6131
Melbourne, FL 32902			FAX   : (407) 727-{5118,5227,4004}

Gee, Beaver, everything that's fun can get you in trouble.  Haven't you
learned that yet? --Gilbert

ray@hydroplane.cis.ohio-state.edu (william c ray) (08/24/89)

In article <4791@portia.Stanford.EDU> rick@hanauma (Richard Ottolini) writes:
>
>Plate #22 in Upstill's RenderMan companions is the "shattered globe" image
>that recently appeared as a National Geographic cover hologram.
>Could someone explain how this synthetic image was converted into a hologram?
>Thanks.

Relatively 'easily'...

The technique is described rather clearly in 'Holography Handbook', by
Unterseher.  decent all around holography handbook for practical holography
from beginner to advanced level.

Anyway, the method is to render successive views of the object from different
directions,  (the same method was used for making the 'Leslie' hologram, if
anyone remembers her), and then using an cylindrical lens, the images are
projected onto vertical slats of the hologram film, (obviously along with a
reference beam, or else we'd just have black lines on the film), typically
in the range of .5-1mm wide.  Each frame/image is projected in this manner,
onto successive slats of the film.  Once finished, process as usual, and make
contacts, or whatever.

When viewing, the trick is that each eye sees a different hologram because
of the difference in the eye-image angle for right and left eyes.

(disclaimer... this is VERY basic, and not intended to be a recipe for do-it
yourself computer holograms...  
Do Not Try This At Home Children... This trick is being performed by TRAINED
professionals, and is VERY dangerous... etc etc etc)

hope that helps
Will Ray

talent@dover.sps.mot.com (Steve Talent) (08/24/89)

In article <4791@portia.Stanford.EDU> rick@hanauma (Richard Ottolini) writes:
>
>Plate #22 in Upstill's RenderMan companions is the "shattered globe" image
>that recently appeared as a National Geographic cover hologram.
>Could someone explain how this synthetic image was converted into a hologram?
>Thanks.

The issue of National Geographic with the hologram on the cover uses a real
hologram.  There's an explanation of how the hologram was created on the 
inside back cover of that issue.

The image is actually a double exposed hologram - one image of the globe in
freefall exposed by a pulsed laser, the second image was taken while the 
globe was being shattered from the impact of a BB fired from an air rifle.

Check it out!  It's fascinating... and expensive to produce.
-- 
Steve Talent, Motorola Semiconductor Products Sector CAD
Mesa, AZ  602-994-6801,  ...!{oakhill, sun!sunburn, uunet}!dover!talent

efo@pixar.uucp (efo) (08/28/89)

>>Plate #22 in Upstill's RenderMan companions is the "shattered globe" image
>>that recently appeared as a National Geographic cover hologram.
>>Could someone explain how this synthetic image was converted into a hologram?
>>Thanks.
As many have pointed out, the December cover hologram was live-action,
made by exploding a real glass sphere.  Our computer-generated shattered
earth was made independently, although also for the Geographic.
The idea was to create an image that was evocative of a shattered glass
globe -- perhaps more evocative than an actual photograph.
We produced a short sequence of the earth "exploding;" this was shown
in the marketing film presentation at Pixar's Siggraph booth.

We have produced holograms from our images, however.  The image on the 
cover of the July 1988 IEEE CG+A was a hologram of the baby and toy
in "Tin Toy".  We supplied ABN with a sequence of high-resolution
images of the scene rotating about its center; through expensive
magic, ABN turns these into a single hologram.

aaa@pixar.UUCP (Tony Apodaca) (08/29/89)

In article <6490@pixar.UUCP> efo@pixar.uucp (efo) writes:
>cover of the July 1988 IEEE CG+A was a hologram of the baby and toy
>in "Tin Toy".  We supplied ABN with a sequence of high-resolution
>images of the scene rotating about its center; through expensive
>magic, ABN turns these into a single hologram.

Before anyone asks, ABN == American Bank Note.
This is the company which makes the two holograms that every
man and woman in America has in their pocket (or equivalent)
this very moment...  the VISA and MasterCard emblems.

"If I had a penny for every credit card in America...."
-- 
UUCP:		{sun,ucbvax}!pixar!aaa		Tony Apodaca
ARPA,BITNET:	aaa%pixar.uucp@sun.com		Pixar, San Rafael, CA, USA