.....so shooting film in motion picture cameras means when you start rolling you see the effect of the film passing in front of the gate and you get a 'motion blur' images in your viewfinder (for want of a better technical term!)....if you have your eye in the viewfinder that is.....one-man band mode of course
.....so does this mean camera movements are always pre-planned or should you just practice focusing the 'blurred' viewfinder image cos with time you get used to it and you can flow with the scene better???
thanks for your time everyone....look forward to getting some good tips
Hi Stephen, there are two separate issues in your question:
First, is about strobing when panning the camera. As the film standard is 24 frames/sec, if you pan too fast you get jumping in the image. If you pan really fast, it's all just one big blur, which is usually ok. If you pan with a moving object (car, actor, etc) it works out fine and one doesn't notice the strobe effect in the background. This is true shooting film or digital at 24 fames / sec.
BTW, the blur is not caused by the film moving through the camera. When the shutter is open, the film is static. It only moves when the shutter is closed.
The second issue is about seeing focus through the viewfinder. In all "modern" reflex movie cameras, the viewfinder blacks out while the film is being exposed and the image is visible only while the shutter is closed and the film is moving through the gate. This causes a distinctive flicker in the viewfinder. Seeing focus through the viewfinder ground glass is not easy even when the camera is not rolling. It's not like an SLR where you view focus with a wide open aperture. So it can be quite dark when shooting ISO 400/500 film. And when the camera rolls, and the flicker starts, it can be quite tough to see critical focus. It takes quite a bit of practice to see the focus on a rolling movie camera, and even then, one can be unsure when the focus is close, but not quite critically sharp.
To solve this, one uses a crew member, or "focus puller" to change the focus according to the distance to the subject using the distance scale on the the lens barrel. This is a challenging job that takes years to get really good at.
If you don't mind a bit of "out of focus" documentary film style, you can change the focus by eye while you shoot. If you need the critical focus demanded by narrative cinema, then, yes, rehearsal, focus marks (marks on the floor to get actors in the light, and in focus), and a good focus puller are required. A good focus puller can sometimes just "wing it", depending on the lens, aperture, distances involved. If they are really good, they will tell you when "winging it" is beyond their ability. But often, they just complain and do their best!
Happy shooting Stephen and enjoy your filmmaking adventure!!!!