Posted 09 May 2007 - 11:51 PM
Posted 10 May 2007 - 12:09 AM
The hyperfocal distance is the distance where, at a certain f-stop and with a certain focal length, you get the most depth of field possible, usually to infinity although there are some exceptions. A general rule of thumb is when at the HFD, 1/2 the distance from the HFD to infinity will be in focus. Something else to remember is that the HFD is not the figure you set your lens barrel to. HFD's corrospond to certain distances.
Hope this helps.
Posted 10 May 2007 - 01:02 AM
Posted 10 May 2007 - 01:55 AM
You can be a DP and go an entire shoot without looking through the eyepiece if you have video assist and a good operator with reliable AC's.
As far as hyperfocal distance...that's almost the same as Depth of Field which can always be calculated mathematically or assumed by consulting DoF charts. So long as your lens is accurate as evidenced by focus tests, and it's set for critical focus on your main subject, you should be fine. Otherwise, go Gillliam and use only wide-angle lenses where hyperfocal distance is almost always evidenced.
Edited by Jonathan Bowerbank, 10 May 2007 - 01:58 AM.
Posted 10 May 2007 - 10:16 PM
At any given apature you have a depth of field. all within that depth of field will be "aceptably sharp" at least to the folks who calculated the depth of field tables..
How does hyperfocal distance work? Thanks!
If you take a small appature, like f-11 and set your lens so that the infinity mark is on the edge of the depth of field, the closet object that will be in focus whould be at half the distance you are focued at. To take a typical example, you may find that a 10 ft setting will put infinity at the f-11 mark on one side, and 5 ft at the mark on the other. SO everything from 5 feet out to infinity would be "in focus"
Problem is of course that often you _don't want_ everthing to be in focus, you want to direct the viewers eye. that is why you see folks squinting through those 85N9 filters so that they can open up the lens to get a small depth of field.
This is why the seting is often done by seting the lens scale insted of looking through the lens. The shot may have two or more Changes in focus as the action moves from forground to background.