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sampei
09-05-2010, 02:44 AM
hi, I was recently doing some tests with the depth of field settings, I had a look at the manual but there's still a couple of things I'm not sure about. Basically the focal distance is the distance between the camera and the point where the focus will be 100%, and the FSTOP determines the range (or radius) that will encompass the focused area. How do I calculate the range ? I've found that multiplying the focal distance times the FSTOP might give me the result I'm looking for: for example if my focal distance is 4m and my FSTOP is 2.0 therefore 4 * 2 = 8m. So 8m would be the range of my focus with its centre being 4m from the lens. I've done some tests and this could be true, but I don't understand how the focus' falloff is calculated from outside the range.
Also can somebody explain the "diaphragm sides" and "diaphgram rotation" fields ? thanks in advance ;)

Lightwolf
09-05-2010, 03:04 AM
You can apply the Depth of Field Custom object to a Null and parent that to the camera (at 0,0,0) and it will show you the effect of the F-stop and other settings in the OpenGL views.

The sides and rotation control the shape of the blur in the out of focus area - also called Bokeh (you can google that).

Cheers,
Mike

sampei
09-05-2010, 03:29 AM
cool, thanks for the pointers Mike...the scene I'm working at the moment is quite heavy so Im using the bounding box option in the camera view, but Ill give that custom object a try. Ok, lets see what this bokeh is :thumsbup:

Lightwolf
09-05-2010, 03:41 AM
cool, thanks for the pointers Mike...the scene I'm working at the moment is quite heavy so Im using the bounding box option in the camera view, but Ill give that custom object a try.
That's perfectly fine. The custom object basically draws a (slanted) box around the space in your scene what will be in focus.

Cheers,
Mike

sampei
09-05-2010, 03:51 AM
sweet, that sounds quite helpfull.
I'm reading about the "bokeh" thing, interesting stuff. Actually I just received a powershot g11 and im waiting for a couple of books on photography from amazon, so Im eager to start digging into the subject :D

dwburman
09-10-2010, 01:58 PM
Also, if you're in LW9.6, you can turn on DOF/MBlur Preview in your camera's viewport to see the effect in your viewport. It can be slow though so try it in Bounding Box mode first.