Another method is to make a large hole in the cardboard, and paste over it a piece of tinfoil and make the pinhole in this.
Mark this with a pinhole at top and bottom, turn the cardboard over and draw a line from pinhole to pinhole; then score it on this line that the door may open properly outward.
Make a pinhole at each end of the two lines forming top and bottom of the front of the room A and B, then turn the paper over and draw a top line and a bottom line across on the wrong side of the paper from pin-point to pin-point.
In a pinhole camera the cones are so small that they cannot overlap, so there is no one place where the image is better than elsewhere; in other words, there is no necessity of focusing.
Perfect pictures can be taken with a pinhole camera wherever long exposures are possible, or wherever the object shines brightly enough.
There is one thing about the way in which light is brought to a point by a lens that makes the formation of images by this method troublesome in comparison with their formation in pinhole cameras.
Even pinhole snapshots are possible where the light is abundant, with a ten to fifteen second exposure.
It was the pinhole photograph, a little blurry, but quite convincing.
This," he explained, "is what is known as a pinhole photograph.
Put the solution in a long, slender bottle, closed at the top with a piece of bladder' containing a pinhole to admit air, says Metal Worker.
Trim the edges of the cardboard to match the shape of the disk, and make a pinhole in the center.
I thought I knew, and, seizing a powerful magnifying glass from the litter of my pocket-pouch, I applied myself to a careful examination of the marble immediately about the pinhole in the door.
As nothing special, neither paper, glass negative, nor developer, was used, this process of pinhole photography deserves special mention.
The injury consists ofpinhole defects in the sapwood and heartwood of felled trees, sawlogs and like material which have been left in the woods or in piles in the open for several months during the warmer seasons.
In the case above mentioned of fatal haematemesis from miliary aneurism over an hour of continuous searching was required to find the pinhole perforation in the mucous membrane in the bottom of which lay the small aneurism.
Well, I will get a picture with my pinholecamera even if I have no lens.
It's closed up all right," said Billy Manners, covering the aperture of his pinhole camera.
Billy had faith in his pinhole camera, because it was his.
That your pinhole camera is all right," said Percival, "and that this mysterious man with the white mustache is still in the neighborhood.
Did you never hear tell of a pinhole camera, my boy?
In the course of something more than an hour Jack had completed his work and showed a much larger print of Billy's pinhole photograph than was possible from the original plate, and also a print from the latter.
Well, my pinhole camera has turned out all right, hasn't it?
And she might have inserted just below the pinhole the illuminating note that, after unfastening the string, Dalton had forgotten to return it.
Jelliffe has just brought into ridicule what he terms "pinhole psychiatry;" but as I remember it, there is a technical method in psychology whereby things may be more clearly visible through a pin-hole!
On the other hand, a man who has a mind no bigger than a pinhole is too circumscribed to be capable of understanding any very broad generalization.
The aperture of any lens can be measured by focussing a distant object, then replacing the focussing screen by a sheet of cardboard with a pinhole in the middle of it.
