I know it can be difficult when shooting in a very small room to achieve a very shallow depth of field and throw the background out of focus. Will shooting into a mirror effectively double the distance to the subject allowing to the use of a more telephoto lens setting (thereby achieving less DOF)?
Re: Depth of Field by John Sharaf on Nov 4, 2002 at 7:28:38 pm
Todd,
That's an interesting concept, but to be certain of the effect you should check the depth of field charts in the Cinematographer's Manual or other source, using the actual distances and focal lengths involved. In liue of the charts, an actual observation should suffice. Of course, you'll have to flip the image in post to preserve the accuracy of the facial features.
Remember that even though the distance to the subject would be about twice as far in the mirror, the distance to the back wall might not be twice as far! If it were, it would mean that you've staged your subject against the wall minimizing the difference.
The real difference will be revealed by the change in the focal lengths of the lens to effect a similar frameing. If you have to zoom in considerably on the mirror (more telephoto) to match your intended frame size, you probably will accomplish your objective.
Another alternative is to cast an out of focus pattern, either with a Leko type light or other form of gobo shaddow maker that will enhance the illusion of out-of-focus depth.
Re: Depth of Field by Shooter on Nov 5, 2002 at 3:00:02 am
You must use a front surface mirror. Regular mirrors have the silver on the BACK side of the glass. You are shooting through the glass to the mirrored surface and you will get a ghost image. Special effects guys sometimes use mirrors for optical effects and they use front surface mirrors. Sorry, can't tell you where to get them.
