DSLR's use the Live View feed to produce the movies. They are not actually pulling a full-resolution feed from the sensor and the shutter is functioning as if doing a long exposure, there is also an increased noise penalty from doing this (partially from heat, partially from not resetting the sensor between frames which requires the shutter to close). Additionally the only exposure controls are aperture and ISO in this mode, there is nothing analogous to shutter speed, unlike with film (where fps controlled the defacto shutetr speed, video is shot with fixed framerates)
Running the sensor in full-resolution mode works differently, the only way to control shutter speed is with the mechanical shutter which is linked to the mirror at a minimum. So you have to fire the shutter with each exposure when taking stills. -Adam On Tue, May 18, 2010 at 5:00 PM, Joseph McAllister <pentax...@mac.com> wrote: > Makes it a miracle that the Pentax and other DSLRs can take 24 - 30 fps > movies then, doesn't it? Yet how quietly the shutter operates at that speed. > > On May 12, 2010, at 10:20 , David Parsons wrote: > >> Mirror, shutter, and aperture control are not mechanically linked in >> modern dSLRs. They are separately actuated using servos. >> >> They are most likely setup that way because the timing chain is >> already setup and it's much easier to tell the camera to actuate 3 >> times, than to reprogram the timing chain to lift the mirror, close >> the aperture, and open-close the shutter x times. >> >> On Wed, May 12, 2010 at 12:13 PM, Godfrey DiGiorgi <gdigio...@gmail.com> >> wrote: >>> >>> Of course it needs to operate the shutter ... all electronic shutters >>> as yet do not have the control and resolution possible with a >>> mechanical shutter. And like with most SLRs, the shutter regulation, >>> aperture control and mirror are a linked mechanical operation so >>> there's no good way to cycle the shutter without also cycling the >>> others. >>> >>> On Olympus bodies, the auto-bracket feature and the "capture three on >>> one shutter press" are implemented separately: you have to turn on >>> auto-bracket AND drive mode to achieve this automation. I find this >>> very useful in some situations (say when using a flash unit to allow >>> time for recycling). >>> >>> If a camera has independently, electronically controlled shutter, >>> mirror and aperture operation, then an option to do auto-bracketing on >>> one press cycling only the shutter as quickly as possible would be a >>> nice feature for use when appropriate. I don't believe it's possible >>> with the design of today's Pentax (or any other) SLR bodies. >>> >>> On Wed, May 12, 2010 at 8:10 AM, Larry Colen <l...@red4est.com> wrote: >>>> >>>> On Monday night I was photographing a dance and was having a really >>>> rough >>>> time with exposure. I was shooting in manual mode, I'd take a picture, >>>> then >>>> the next time I shot, the exposure was way off. Or it would change. It >>>> took me a while to realize that I had left the shutter in "bracket". > > Joseph McAllister > pentax...@mac.com > > http://gallery.me.com/jomac > http://web.me.com/jomac/show.me/Blog/Blog.html > > > > > > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
