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Old February 23rd 06, 01:12 AM posted to
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Default Why do digital cameras need shutters?

On Wed, 22 Feb 2006 19:57:54 +0000, (Tony Hall)

Måns Rullgård wrote:

"Steve" writes:

I hope this isn't a silly question. Is it impossible or too
expensive to turn the sensor on and off or something instead of a
mechanical shutter? Just wondering.

It's possible, but slow and inaccurate. It is found on some cheap
(phone) cameras.

Not quite true. The Canon EOS1D used its CCD to control exposure while
the shutter was reduced to protecting the imager and keeping dust off,
it also meant you could use a 1/500th sec flash sync.

The MkII which replaced it (and MkIIN) use a CMOS imager so it's back to
using the shutter for controlling exposure, and sadly back to 1/250th
sec flash sync.


Flash synch, 1/4000th of a second. Not a DSLR.