Soft Focus Back grounds (Shallow DOF)
Posted 06 September 2007 - 03:09 AM
Any Suggestions would be welcomed!
Posted 06 September 2007 - 10:44 AM
Edited by Robert Hughes, 06 September 2007 - 10:45 AM.
Posted 06 September 2007 - 12:55 PM
...I ve asked the focus puller to roll the focus forward on the lens as well.
A. Any suggestions on what I should try?
B. Should you be able to see this effect in the viewfinder?
If you set the focus just a little in front of your subject (but still have the depth-of-field so he/she is in focus), then that could help you in softening the background a bit more.
A: Shoot at wider apertures with longer lenses, and make sure there's enough room for you to move the camera back far enough. I was on a shoot once (shooting SD on a Panasonic DVX) where I was in an 8' x 10' room. The director wanted a wide shot of the actress but still wanted the shallow depth of field, even though I was only 4' from her...it was impossible under those conditions. So keep that in mind when scouting locations.
B: When looking through the viewfinder, you can't really trust your eye when working in shallow DoF's. Check your measurements, check the DoF chart and make sure you know what is and isn't in focus.
Posted 06 September 2007 - 01:03 PM
Posted 06 September 2007 - 01:35 PM
Posted 06 September 2007 - 03:52 PM
Depth of Field is directly related to focal length. Wide angle lenses such as 20mm lenses inherently have a very wide depth of field.
No, DOF is not directly related to focal length.
It is directly related to f stop and image reproduction ration.
The image reproduction ratio is a function of film area, distance to subject and field of view. Wide angle lenses have a larger DOF because they reproduce a smaller image on film than a longer focal length would. The same happens when you move closer to your subject. DOF decreases because the subject is reproduced on film at a larger scale. That is why e.g. in macro photography DOF is so extremely small, many times only a fraction of a millimeter is in acceptable focus.
The whole concept of DOF is prone to causing confusion, I hope that clears things up a bit.
Read the article on wikipedia: DOF.