Argus Camera ARGUS A2 manual Closer Two-Position Focus

working filter factor. This factor will remain the same for every mask that is similarly made.

Because of ambient dust and scratches, the mask will not last long before it needs to be removed or replaced. The light-proof ribbon will also dry and begin to sprinkle dust on the filter. Allow it to dry out completely after removing the filter to prevent the ribbon from getting moldy.

The Closer Two-Position Focus

The focusing mechanism on the Argus A and A2B is limited because it can only focus at two distances: Infinity to about 15ft, and about 15ft to 6ft. This modification allows the user to temporarily shorten these distances to take closer pictures.

Before we begin, however, we must undertake a short discussion about the two- position focus.

Focus, of course, can only be set for one distance. Depth of focus gives us a range within which the sharpness of objects is still acceptable. Unfortunately, the definition of “acceptable” has changed considerably since 1936. Adding to the confusion is Argus’ constant redefinition of the distances for the close-up focus position. This range started at 6ft to 12ft, then became 6ft to18ft, and finally settled at 6ft to 15ft.

The best action to take in order to determine the true focus distances is to test the camera for the correct distance. Use the “Ground Glass” method described earlier in this chapter to determine the distance at which the image is sharpest, and then try to take all of your pictures from this distance. Don’t forget to use the smallest practical aperture when taking pictures to increase your depth of focus.

This modification adjusts the original focusing distances into two closer ones. The only drawback is that the photographer loses the ability to focus at infinity, albeit temporarily.

Begin by unscrewing the four screws that hold the Neck and Shutter assembly to the Body. To shorten the focus distances, the distance between the negative and the lens must be increased. This can be accomplished by placing some sort of spacers between the Body and the metal plate with the Locking Lugs.

These spacers can be made of any material, so long as it is hard and of uniform thickness. Flat washers for 4-40 screws are available at any hardware store and are excellent. Thin cardboard also work well. These spacers should not be much thicker than 1/16th of an inch, however, because these screws support the Neck and a knock on the Neck may rip the screws out. If the spacers are 1/16th of an inch thick, the infinity position focusing distance drops to about 10ft and the close-up position distance drops to about 4ft.

Place the spacers on the Body and reattach the four screws. The metal plate with the Locking Lugs should now hover away from the Body. Line the outside edges of the metal plate with an opaque adhesive tape, like black vinyl electrical tape. The tape is necessary to prevent stray light from reaching the negative.

The modification is now done. The camera still has two focusing distances, but they have been shortened considerably. To determine the new focusing distances, use the “Ground Glass” method.

When you want to revert back to the original configuration, simply remove the spacers and the tape.

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