Hasselblad 1000 F, User Manual

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Aperture and Depth of Field
When you focus the Hasselblad on a given object, the image of that object will be really sharp on the film. Things nearer or farther
away wll be gradually less and less sharp, until they are noticeably blurred. The range of distances over which objects are still
acceptably sharp, before you do notice the loss of definition, is known as the depth of field.
You can control the extent of this sharp zone by the lens aperture. As you stop down the lens, the zone of sharpness grows in both
directions; as you open up the lens, its depth decreases.
You can obtain the actual zone of sharpness at various apertures and distances from tables, but in practice the most convenient way is
to use the depth of field indicator.
0n the lenses for the Hasselblad 500C and Super Wide C this consists of two red pointers above the distance scale of each lens. The
pointers are coupled to the aperture setting. They automatically close up at large apertures and move apart at small apertures. One
pointer indicates the near, the other the far limit of the depth of field for the distance and aperture the camera has been set to. For
example, on the standard lens of the Hasselblad 500C, at 25 ft. and f8, you will find the two pointers opposite 15 and 50 ft., so you
have a sharp zone from 15 to 50 ft. At f 16 the distances opposite the pointers may be 12½ ft. and infinite respectively.
Hasselblad 1600F, 1000F and Super Wide have a special scale of aperture numbers marked opposite the distance scale. There are two
sets of such numbers from the largest stop (f 2.8) to the smallest (f 22) on each side of the focusing index (the mark that indicates
the distance to which you have set the lens).
You will also notice that the depth of field is greater at far distances than at near ones.
Two more points on depth of field.
First, the depth obtained depends also on the focal length of the lens. Short focus lenses yield more depth and tele lenses less depth.
That is why the alternative lenses of the Hasselblad have their own depth of field indicator.
Secondly, the sharp zones obtained by the scale or indicator are based on a somewhat arbitrary assumption of how much blurring is
acceptable. So depth of field data to, different cameras with the same lens may not always agree, and you are also quite safe in
rounding off figures obtained from such data. And if you intend to make really big enlargements from your negatives you can use
stricter standards of sharpness by simply stopping down the lens by one stop.
Zone Focusing
With action subjects and similar occasions where you want to shoot quickly, determining sharp zones even with the depth of field
indicator wastes too much time. There you need prepared settings covering given near and medium distance ranges that you can easily
memorize and set on the camera. Then you only have to worry about keeping the subject within that zone while you shoot.
DEPTH OF FIELD
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