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While testing my new Nikon P7800 i came across the fact, that it cannot shoot at 1/4000 s through its entire aperture range, which is f2 - f8 @ 24mm (full frame equivalent).

At f2 i can only go down to 1/2000 s, which increases step by step with higher apertures (f2.8 allowing 1/2500 s, f3.5 @ 1/3200). Only at all apertures higher than f4.5 it allows the full 1/4000, which i was expecting to be the standard the whole time, like it is with a DSLR.

I cannot think of a reason myself and found nothing by googling the question.

mattdm
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user2664856
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    If your camera has a leaf shutter, it could be a mechanical limitation of the design. See http://photo.stackexchange.com/q/45705/15871 Although the discussion is about a different camera, the concept is the same. – Michael C Mar 29 '14 at 16:10

1 Answers1

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The is uncommon yet occurs with several camera models. The smaller the aperture, the less distance the shutter needs to travel and so the faster it can go. This is most common with leaf shutters and cameras which use the aperture as shutter, meaning there is only one mechanism.

Itai
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  • Single mechanism.. I know how it goes with a rangefinder, but how does a digital camera operate a single mechanism aperture-shutter? My guess is the aperture is first fully open, to let light reach sensor for LiveView display. Then apertureblades close fully -> camera clears sensor -> aperture works the role of a shutter to let light in -> aperture closes fully to end the exposure -> aperture opens fully to let LiveView see the light again. Or what is the sequence? – Esa Paulasto Mar 30 '14 at 11:44
  • That sounds about right. Indeed the part about closing the aperture to clear the shutter first is crucial is it always is being exposed for Live-View. Sometimes the end-cycle is done with an electronic shutter. – Itai Mar 30 '14 at 15:14