I shjould fix these numbers, they were hastily written when half asleep
maybe you want to put it that it's about angle of view.. so say a 50 mm
lens will show around 50 degrees, a 100 about 15 degrees, a 500mm about 2
degrees and a 1000mm about 1 degree on a 35mm lens. roughly..
Now ask them to imagine from their left to their right is 180 degrees
(show them a fisheye pic) then ask them to imagine 180th of that, one
degree - that's all that will be encompassed in a 1000mm shot.
It'll still be the same size image as the wide angle shotyou showed them,
just ateeny portion of it made bigger
for 35mm format 24x36mm sensor the focal length and angles are:
28mm = 75 degrees
50mm = 43 degrees
100mm = 25 degrees
250mm = 10 degrees
500 mm = 5 degrees
1000 mm = 2.5 degrees
