Week 5

The ideal shutter should
Expose each part of the film/sensor equally and simutanlesly
Be silent inopertaion
Be vibration free
Little effort to set in motion
Take minimal time to open and close
Effective exposure should be repeatable

Focal plane (FP) shutter
Flash should only operate when shutter is fully open
Flash synchronisation is therefore limited
In order to achieve very fast speed the 2nd curtain is released soon after the first to follow it across the shutter window or “gate” as a “slit”

Between the lens or leaf shutter
Operates between lens elements
Must be “cocked” during lens attachment/removal
Maximum speed of 500th sec due to mechanical limitations.
Synchronises with electronic flash at all speeds
Most medium format cameras
Accuracy is affected at high shutter speeds and when wide aperture are combined with high shutter speeds eg: 1/500th sec
At 500 a greater proportion of the time is used to open and close the shutter so exposure is actually less than expected.
Often 400 is used, inefficiency reduces exposure closer to that ideal 500th sec
Shutter opens and closes at the same rate regardless of shutter speed chosen
Shorter time to uncover a small aperture
Motion and shutter speed

Depth of field
The region of acceptably sharp focus around a subject position, extending toward the camera and away from it, from the plane of sharpest focus
The boundaries of dof are referred to as the near limit (d1) and the far (d2).

Subject distance(u)
Controlling- aperture, lens, shutter speed
Increased- smaller apertures, using larger subject distances, using wider angle lenses