BetterPhoto Q&A
Category: New Answers

Ben F		Hyperfocal Distance Q Okay, I understand the details of setting the camera to hyperfocal distance.. eg, shooting a pic at f16, I would line up the infinity mark against 16 on the DOF scale. HOWEVER, I have a 90mm lense which covers the same apertures as my 45mm, ie 4, 5.6, 8, 11, 16, 22. EXCEPT on the depth of field scale I only have 16, and 22... Not the whole lot like my 45mm lens. Therefore I can only set for hyperfocal distance when im shooting at f16 or f22? Is this correct? The problem is that ive noticed, is on the depth of field table ive got, the 90mm lense has not as wide DOF's as the 45mm. By that I mean the focus range does not extend as much in front of and beyond the point of critical focus. Which stinks!!!.. I have another question. If I set my 45mm lense at f16 and focus at 3 meters, I get in the range of acceptable focus 1.72m - 12.7meters. Okay, would anything beyond say 13 meters look completely out of focus, or does it get progressively worse???? so something at 15 meters could still look in focus however is not compared to the point at 10 meters??? Also, aperture affects DOF, so if im shooting a small aperture of f16 or f22, would the falloff in focus outside the focus range be more gradual than if I was using a larger aperture (Which has less DOF) say f5.6 or f8 in comparison? Hope someone understands my question????? Thanks To love this question, log in above August 14, 2005

Peter M. Wilcox		Here's a good link that explains it: http://www.luminous-landscape.com/tutorials/understanding-series/dof.shtml To love this comment, log in above August 14, 2005

Jon Close		Peter suggests a good link. In general, shorter focal length lenses give greater depth of field at each aperture than longer focal length lenses. For a 90mm lens the DoF is too compressed for it to be practical to print the DoF scale for any by f/16 and 22. At any aperture there is only a single plane of sharp, critical focus. Objects closer or farther than this distance will gradually be more out of focus. To love this comment, log in above August 14, 2005

Michael H. Cothran		Often there are marks for other f-stops, but not enough room for the manufacturer to engrave the actual f-stop. Nikon has a "color" system with their MF lenses, so different color lines would match the f-stop of the same color. If your lens has other markings, then these are probably for other f-stops. Michael H. Cothran www.mhcphoto.net To love this comment, log in above August 15, 2005

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