it's not easy...
Creating panoramic images is more than just pasting a few images
The human eye sees the world projected onto a sphere that wraps
around your body. The center of this sphere (or two slightly overlapping
spheres, really) is in the middle of each eye.
Photographs are small pieces of that world sphere that you see,
that have been squashed flat for printing on paper.
When you try to put these flat pieces of paper back together
again, they never really line up properly. If you have ever tried
to build something round with flat stuff, you'll know the problem.
The problem gets worse when you add the different exposures for
each photo. Modern cameras with auto exposure will determine the
best exposure for each shot. However what is "best"
for one shot will probably be a bit different for the next shot.
What you end up with is a series of lighter or darker images
so that the composite panoramic image looks striped with dark
and light vertical bands.
If you try a full 360 degree panorama outdoors, at least one
of your shots will be into the sun and one will be directly away
from the sun. This will result in a large exposure variation acrcoss
the shots, and a very banded image.
so how do you solve these problems...
This is where our panospace™ technology comes in.
If we are trying to do a 'humpty dumpty' and re-create a sphere
from a bunch of pieces, then we need to bend these flat pieces
into round spherical pieces.
It turns out that the radius of the sphere is related to the
focal length of the lens that the image was taken with. A wide
angle lens creates a tighter sphere with a smaller radius, a telephoto
lens with a longer focal length will create a larger sphere with
a longer radius.
You also need more longer focal length shots to cover the same
amount of area as fewer wide angle shots - sorta logical isn't
This is where the computer comes in handy.
Digital photographs are just an array of pretty coloured dots
arranged in rows and columns across a flat page. With some fancy
cartesian to polar coordinate mapping mathematics is is possible
to distort the flat array of coloured dots into a partly spherical
array of coloured dots - ready for joining with other similary
distorted images to form a panoramic image.
Daltech, my software company has developed our own panospace™
software for image distortion and stitching. This software takes
camera settings such as focal length, exposure data and sun bearings
for outdoor shots and uses it to adjust spherical distortion,
exposure values and light polarisation to create seamless, consistent
exposure images that make you really feel like you are part of
We use several cameras depending on the situation.
Nikon Coolpix 850 - A little 4 megapixel camera
that is absolutely bullet proof. It's relatively low cost makes
it ideal for extreme situations. Most of the aerial shots have
been taken with the Coolpix mounted to a glider or powered plane
wing or tail. Shots are either taken with the built in timer,
or triggered by a very long home made remote shutter release gaffa
taped to the plane.
Minolta Dimage 7I - A very versatile piece of
kit that copes with anything except low-light focussing. The lens
on the Minolta is a gem - wide angle (28mm) to telephoto (200mm)
allows it to capture and frame just about anything. 5 megapixels
is enough detail for most outdoor shots, the ccd has relatively
low noise and the colour reproduction (especially blue skies and
water) is amazing.
Konica Minolta A2 - This is basically a Dimage
7I with an 8 megapixel sensor and a 1.1 megapixel electronic view
finder. The anti-shake mechanism is very useful for low-light
hand held situations (such as panoramics of exotic car dashboard
or engine bay shots).
Nikon D100 - Is the implement of choice for
all indoor shots and action shots. Very fast auto focus, great
flexibility with shutter and aperture settings, crystal clear
lens, but doesn't seem to capture the great outdoors as well as
Tripod Mount - To minimise problems with spherical
distortion and image stitching, we have built our own panoramic
tripod mounts specifically for each camera. Theoretically, the
center of our sphere of view is in the middle of each eye - so
too with the camera.
The 'hyper-focal point' is the point where the light converges
to a single point within the lens. By rotating the camera around
the hyper-focal point the center of the sphere of view is always
Since the hyperfocal point is inside the lens (and that will
move with different focal lengths in zoom lenses) a special camera
specific tripod mount needs to be made. We make ours out of 12
mm perspex sheet that is folded to form a bracket to hold the
camera at the appropriate point over the tripod swivel point.