Originally Posted by Alexz
I visited the Badger Graphic website and found that the Shen HZX-IIA has a maximum bellows extension of 360mm. With a little bit of math it is easy to find that with this much bellows, one could focus a 300mm lens (of normal design) as close as about 1.8 meters.
(1/focal length) = (1/object distance) + (1/image distance)
(1/object distance) = (1/focal length) - (1/image distance)
object distance = 1 / ( (1/focal length) - (1/image distance) )
and substituting in known values, we have at once...
object distance = 1 / ((1/300) - (1/360))
= 1 / ((6/1800) - (5/1800))
= 1 / (1/1800) = 1800mm
Last edited by BradS; 12-01-2005 at 07:34 PM. Click to view previous post history.