Argus Camera ARGUS A2 manual Optimum hole specifications for various shutter positions

pixels, and 1200 should have 75 pixels. Once you have double-checked that your scanner is properly set, scan the strips of aluminum foil and zoom in on the holes. Count the number of pixels that fit lengthwise in the hole and divide by the dpi setting. That will give you the correct diameter of your pinhole. For example, if the scanner is set to 600dpi and the hole is 9 pixels across, the diameter of the hole is 0.015 inches. (9 ÷ 600

=0.015). Table 8-2 indicates the various hole diameters that will produce the “sharpest” pictures.

	Optimum	Approx.	Approx.	Approx.
Shutter Position	Hole	Pixels at	Pixels at	Pixels at
	Diameter	300 dpi	600 dpi	1200 dpi
Shutter in storage position	0.0113 in	3.5	7	13.5
Shutter in extended position	0.0128 in	4	7.5	15.5
Variable Neck focused at 1.25 ft	0.0136 in	4	8	17

Table 8-2: Optimum hole specifications for various shutter positions

Set the Shutter to either B(ulb) or T(ime), whichever you intend to use. The shutter speed cannot be adjusted once the aluminum foil is mounted. Ensure that the aperture is set to f/4.5. Remove the cosmetic metal plate from the Shutter by undoing the two screws on the Face Plate. Only the thin metal disc that says “Argus” should come off, not the entire Face Plate. Place the aluminum foil strip, with the black side down, on top of the Shutter where the Lens Assembly would normally fit. Ensure that the pinhole is centered on the Shutter and that the strip in running directly between the two empty screw holes. Carefully replace the cosmetic plate back onto the camera; this should force the aluminum foil to tighten by the pinhole. Make certain that as the cosmetic plate returns to its original position, the screw holes line up; if they are covered by the aluminum foil, tear it away with a pin. The cosmetic plate can be secured in one of two ways: it can be screwed down or it can be taped. If the screws are continuously removed and replaced, there is a chance of damaging the threads or the head of the screw. If taped down, make certain that it is secure. If the aluminum foil has a tendency to tear around the edges when mounted, as some types do, line the outer edges of the aluminum foil with tape.

Some pinholers feel that aluminum foil is not the best pinhole medium. They prefer thicker aluminum like that found on disposable pie plates, or some other thin, opaque material. To mount any other material, you should tape it to the aluminum foil strip using the following technique. Rather than poking a pinhole through the aluminum foil, cover the center of the aluminum foil with double-stick tape (tape that is sticky on both sides). Use a hole-punch or razor to cut a hole in the middle of the double-stick tape. Now take the pinhole medium and press it onto the double-stick tape with the pinhole over the hole you just made. Then mount the aluminum foil strip normally.

Now that the camera is built, the only real problem is to determine the exposure time. Exposure information for the optimal hole diameters of the various Shutter configurations is shown in Table 8-3. The f/16 Exposure Factor is the number used to calculate an approximate exposure time on 100 ISO film. Simply take the exposure time recommended by a light meter at f/16 and multiply it by the exposure factor. For example, if the light meter says that the f/16 exposure time should be 1/100th of a second

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