THE SMA FORUM ARCHIVE
Posted by mojo (Guest), on 2001-03-17 12:10:16
NOTE: the following messages have been transferred from the original SMA.com Message Board
User ID: 1718124 Nov 6th 8:47 PM
Hello all. I was wondering if anyone had any techniques for creating the illusion of infinite landscape (stretching off into the distance). I'm hoping to film an aerial shot at roughly a 45 degree angle, but I can't create the impression of rolling landscapes in the distance with my backdrops. At this point I'm thinking of just cutting to a lower angle, but I was really hoping that this aerial shot would look good. Any suggestions?
mojo aka "the Dude"
User ID: 1718124 Nov 6th 8:53 PM
I'm new to these boards, and just noticed there was another mojo. From now on I shall be known as the dude.
User ID: 8562343 Nov 6th 10:17 PM
Forced Perspecitve is the best way to reproduce distance in miniatures. Basically, forced perspective is creating an illusion by using size to imitate distance. By placing smaller scale objects further back, an illusion of distance is obtained. If you have a large fir tree on your set, and you place another fir, but say half the size, in the background, and view it at a particular angle, the fir tree that is half the size will seem to be almost twice the distance than it actually is in the background. By using smaller and smaller items and placing them further back even more of an illusion is created. A great example of forced perspective is in "The Empire Strikes Back". Since you mentioned that you will be creating an aerial P.O.V., check out the Giant Snow Walker attack on Hoth. The landscape is almost completely miniature and forced perspective is used very impressively. Once you have your "horizon" finalized in the back ground the tiniest prop should be used, or, to enhance reality, nothing at all. It would be where the "sky touches the ground". Hope this helped.
User ID: 0512724 Nov 7th 11:16 AM
Here are some basic helpful hints for
doing a forced perspective miniature.
Since you are working with an aerial
view the placement of your horizon line,
("the apparent junction of earth and sky")
will be all the more important in
creating a realistic illusion.
Whatever height your camera is will
also be the height of your horizon.
The FG miniature should slope gently
up toward this raised horizon. When
viewed from the side your forced
perspective miniature set should
appear to be on a ramp with the
horizon and camera at the same height.
Say that your camera should seem to
be 100 ft in the air, about as high
as a ten story building. This would
dictate that no matter what distance
you might put something 100 ft tall
(a building, hill, Godzilla) you would
want to have your camera even with its
top. This should give you an idea of
how large something should be at any
given distance from the camera.
Anything taller than this (a mountain)
would extend above your camera height.
If you look at a copy of "Evil Dead 2"
in the shot where an arm comes up out
of the ground and in the distance we
see the cabin down in the valley that's
a good example of a forced perspective
miniature. The arm was full size
(stop motion animated be Doug
Beswick) and the rest of the set
was in forced perspective (built
by Jim Belohovek).
The cabin was about 20 inches wide,
built in perspective, and only about
8 ft away from the camera. The sand
worm sequence in "Beetlejuice" had
some very simple forced perspective sets
(worked with Jim Belohovek on
that one too).
One more hint. Build your set to
camera. Since the field of view
widens the further away you get
you will need much less set up close
than you do in the distance.
Viewed from above the set would
be shaped like a pie wedge.
Also, though it contains no
stop motion, GO GET "Darby O'Gill
and the Little People". BEST trick
perspective work EVER and a very fine
Sorry about being so longwinded,
but I do love trick perspective.
By the way, these tricks work in
CG too if the camera doesn't move
User ID: 0701364 Nov 7th 5:53 PM
Jim's the expert in this, but I'll add my low budget 2 cents worth as well. With natural landscapes you can track your camera, because trees exist in different sizes, as well as being different distances - theres a degree of ambiguity, so you don't really give it away. But for a shot looking down a street where you know buildings are made of right angles and the lines of perspective converge, and you know how big everything should be, it doesn't take much movement to make it look wrong. A little atmospheric perspective - soft blue fill light on the more "distant" parts of the set, to simulate the effect of haze (smoke is great for live or high speed but a real problem for stop motion shots) - helps the sense of depth too. I made a wide desert landscape as a series of ramps, the nearest to camera almost level (to animate on), the middle one a little steeper, and the back piece at about 45 degrees, so it caught the light more like the vertical backcloth behind it. The back edge of each piece had hill shapes to avoid a straight line, and concealed a gap for the animator to gain access. My total studio depth is 3.9 metres (about 13 feet) and the set took up 2.7 metres (9 ft) of that. I didn't go for as high a camera angle as the 45 degrees you were aiming for, since the more you look straight down to the ground the less perspective you get. Just by cheating the perspective a lot you're telling the brain that you're not looking down as steeply. (that's what happens in a perspective painting - you're looking flat on at the canvas, but the landscape depicted has an apparent angle which is different.) A 10 or 12mm lens (for 16mm camera) exaggerates the perspective as well, and gives you the deep depth of field you need.
User ID: 8562343 Nov 7th 7:30 PM
Another interesting point about forced perspective is the way things move perpendicular to the camera. If you were to do a tracking shot in stop motion, these different planes mentioned by Jim and Nick would also move at different speeds. The closer moving fastest, the middle slightly slower, and the furthest back hardly moving at all. This is actually a great test to film, if you have the time. Try to fool your eye to believe that these different planes are moving in conjunction with the camera tracking.
the dude (mojo)
User ID: 0087674 Nov 9th 10:07 AM
Some interesting ideas to play around with. I like the idea of using three seperate planes, but I have one question. With a high angle aerial, it would be hard to create distance and perspective with my 10 inch puppets. I was hoping to do a full zoom in on a charachter, but it sounds as if I'm going to have to use a scaled puppet for the shot. Is this true?
-thanks alot for the input guys.
User ID: 9022063 Nov 9th 7:17 PM
From what I understand, in stopmotion, sometimes different scale size puppets are made for particular scenes. Per the making-of Chicken Run and Nightmare before x-mas books, they used this method. Couldn't you use very small puppets for long shots, then, if you do post production on a computer, as you're zooming in closer to the puppet, somehow do a gradual morph into the 10 inch puppet? You can use an overlay of fog or aerial haze effect to kind of hide the transition. You may not get the exact shot you want but maybe can redesign scene to suggest (through editing).
User ID: 0512724 Nov 9th 8:09 PM
In the old (pre CG) days effects artists
would zoom, or dolly, into a matte painting
that would have a small section of live
action rear projected into the shot. They
would time their move so that on the frame
that the rear projection filled the camera
view at 1:1 the matte camera would lock off
but then the move would continue as part
of the pre filmed projected element. In this
way you could seem to enter the matte
painting and move around in the live action
world. It wouldn't be too hard to join up
two elements like this in After Effects
and move in on a larger animated character
in a forced projected landscape. It would
take away from some of the pure fun of
just doing it in the camera but you could
get the shot. I can't think of a good
example just now but the RKO matte dept.
used it all the time. I recall seeing
many examples on Linwood Dunn's reel.