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Hello, I am capturing high-speed videos of water droplets using a PhotonFocus TrackCam (C-mount), capable of 1000+ fps. The lens I was using was a Computar 18-108mm/f2.5-16, that was lying around. I was able to have decent focus for one droplet (diameter of ~1 mm), but was having trouble getting a DOF for multiple droplets close together, shot from a little over a foot away. What lens would you recommend to use in order to have ~5mm DOF with a magnification of 1-2X? The lenses I have found so far online are either capable of doing one or the other (DOF/magnification), but not both. {I am already lighting the scene for 1000+ fps} Any help would be appreciated, Josh

I'm really interested in the ways cinematographers are using differential focus today. For several years now, I've been seeing more and more sequences on film and TV where very shallow DOF is used and, almost inevitably, the actor's movements will take him/her in and out of the plane of sharpest focus during the scene. Increasing use of steadicam and handheld seems to add to this. In the past, in general, I think shots like that would call for a retake or an edit to cover what was once considered a mistake -- but now it seems that DPs (or directors?) are making an aesthetic out of this. I'm just wondering if someone here might be able to point me to any technical, industry, or even academic discussions of this issue -- how DPs go about it, when is a shot a keeper and when not, etc.? Apologies if this seems like a naive question, but I just haven't been able to find anything searching on my own. Thanks for any input.

I'm attempting to film a practical of a company leader and need some help with calculating the size of the various layers. What we're trying to accomplish is this: a camera will track a half moon/crescent shape. In front of it are about four layers that when combined make up our logo. As the camera moves from the side/start position to the middle/end position the layers line up and form the end image. my question is this: since the layers are different lengths away from the camera/lens how do I calculate how large to print each layer. I assume the layers closest to the camera have to be proportionally smaller than the back layers, correct? any help would be appreciated. Thanks!