While tidying away one of the first copies of AP I bought (17 Sept 2005), I came across this revelation (to me at least) on page 28, from Geoffrey Crawley...
Infinity...For photographic purposes it is defined as the object distance beyond which a lens of a given focal length images all planes equally sharply, making further focus movement unnecessary...this distance is often taken as 1000x focal length. Thus for a 50mm lens it is 50m.
Can anyone help me out here? Assuming I'm photographing a landscape with a lens of 24mm focal length, should I:
A. Set the hyperfocal distance one third of the way into the scene, say on an object 500m away, and stop down for depth of field
B. Ignore the hyperfocal distance and set the focus distance to approx 24m and stop down (less) as everything further than 24m will be rendered in focus.
C. Set the hyperfocal distance one third of the way to 24m (approx 8m) and stop down (even less), ensuring that 24m is in focus (and therefore infinity) as there is less margin for error than B.
D: Note that A and B are the same. You don't actually focus beyond 24m when you render an object 500m away in focus and that's why the lens doesn't have a distance scale beyond 24m.
Apologies if this is a dumb question, but I hope you can see what I'm driving at
-------------------- There are two things to aim at in life: first, to get what you want; and after
that, to enjoy it. Only the wisest of mankind achieve the second.
Logan Pearsall Smith (1865-1946)
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Infinity closer than you think?
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