Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-05-2009, 07:35 PM   #31
Veteran Member




Join Date: Nov 2006
Location: Hong Kong
Posts: 1,934
QuoteOriginally posted by alohadave Quote
Interesting. I just picked a Ricoh Singlex from the early '60s that uses a similar shutter from Copal.
Copal has been making those vertical run electronic shutters for all brands for decades. Another maker is Sekio but their shutters are minority.

04-05-2009, 07:37 PM   #32
Veteran Member




Join Date: Nov 2006
Location: Hong Kong
Posts: 1,934
QuoteOriginally posted by Jonson PL Quote
The Nikon D1 had Single-blade mechanical shutter. And the D1x had Charge-coupled electronic and mechanical shutter. They could go up to 1/16,000 sec. With flash sychronization up to 1/500 sec
I don't think there is any "single blade" mechanical shutter on Earth for use in any DSLR/SLR.
04-05-2009, 08:05 PM   #33
Veteran Member
OregonJim's Avatar

Join Date: Mar 2009
Location: Willamette Valley, Oregon
Posts: 1,327
QuoteOriginally posted by denisv Quote
I always thought it had to do with the sensor heating up or something, but with the release of the 5DII and D90 that shoot video by keeping the shutter open and sampling, I've come up with the question why do DLSRs still have mechanical shutters?

Why not just flip up the mirror and sample the sensor electronically on exposure? It'd allow lighter, smaller, quieter, more reliable cameras and faster "shutter speeds" (1/250000 anyone?).
There are several reasons, but the most important one (to me) is:

Electronic shutters generate switching noise, which raises the noise floor even higher as ISO increases. Mechanical shutters do not contribute to sensor noise.
04-06-2009, 12:00 AM   #34
Veteran Member




Join Date: Mar 2009
Location: Perth Australia
Photos: Albums
Posts: 1,514
You cant prevent a light sensitive device from generating electricity unless you block out the light. Without a mechanical shutter the sensor would be generating a signal constantly....

Could use that to charge the battery maybe

04-06-2009, 12:55 AM   #35
Veteran Member




Join Date: Nov 2006
Location: Hong Kong
Posts: 1,934
QuoteOriginally posted by WerTicus Quote
You cant prevent a light sensitive device from generating electricity unless you block out the light. Without a mechanical shutter the sensor would be generating a signal constantly....
Not really.

We can prevent a light sensitive device from generating electricity when the power supplied to it is cut !

As such, switching on and off the power supply to the imager can do the electronic shutter, but of course there are side effects and limitations, too.

QuoteQuote:
Could use that to charge the battery maybe
Ricoh had a SLR called XR-S which used solar energy to power the light meter. But since the solar generates only weak power, it can by no means drive a power hungry monster like a DSLR. XR-S is a mechanical SLR, IIRC, there is even no electronic controlled shutter.
04-06-2009, 05:06 AM   #36
Veteran Member




Join Date: Dec 2006
Location: Copenhagen
Photos: Gallery
Posts: 1,842
QuoteOriginally posted by RiceHigh Quote
I don't think there is any "single blade" mechanical shutter on Earth for use in any DSLR/SLR.
It is stated so, in the DPr specs sheet.

And Nikon themselves say :
"Single-blade mechanical shutter provided for smear prevention"
The Nikon D1

But if it is a typo, and it really acts more like the D1x, it doesn't matter much to me
04-06-2009, 05:34 AM   #37
Veteran Member




Join Date: Nov 2006
Location: Hong Kong
Posts: 1,934
QuoteOriginally posted by Jonson PL Quote
It is stated so, in the DPr specs sheet.

And Nikon themselves say :
"Single-blade mechanical shutter provided for smear prevention"
The Nikon D1

But if it is a typo, and it really acts more like the D1x, it doesn't matter much to me
There are at least two blades for a mechanical shutter to work: one in front and the other behind.

04-06-2009, 07:52 AM   #38
Veteran Member
OregonJim's Avatar

Join Date: Mar 2009
Location: Willamette Valley, Oregon
Posts: 1,327
QuoteOriginally posted by RiceHigh Quote
There are at least two blades for a mechanical shutter to work: one in front and the other behind.
Unless the shutter is circular...
04-06-2009, 09:27 AM   #39
Veteran Member




Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,482
I wonder if I could stand that OP's question on its head and ask, how is it that high-end compact, fixed-lens cameras manage to take such good photos WITHOUT a mechanical shutter?

Will
04-06-2009, 11:34 AM   #40
Veteran Member
alohadave's Avatar

Join Date: Jan 2008
Location: Quincy, MA
Photos: Gallery | Albums
Posts: 2,024
QuoteOriginally posted by WMBP Quote
I wonder if I could stand that OP's question on its head and ask, how is it that high-end compact, fixed-lens cameras manage to take such good photos WITHOUT a mechanical shutter?

Will
They most likely are using a leaf shutter.
04-06-2009, 03:39 PM   #41
Moderator
Site Supporter
Blue's Avatar

Join Date: Jun 2008
Location: Florida Hill Country
Photos: Gallery | Albums
Posts: 17,377
QuoteOriginally posted by WMBP Quote
I wonder if I could stand that OP's question on its head and ask, how is it that high-end compact, fixed-lens cameras manage to take such good photos WITHOUT a mechanical shutter?

Will
Those that lack a shutter do have shortcomings when it comes to objects moving at them or perpendicular to them which results in a slow response times.
04-06-2009, 09:16 PM   #42
PDL
Pentaxian




Join Date: Oct 2006
Location: PNW USA
Photos: Gallery
Posts: 2,128
In P&S cameras with "Live View" the sequence is:
When the shutter button is depressed partway the image is collected via the sensor (shutter is wide open) and the image is shown on the LCD.
When the camera is told (shutter is activated) to take the picture, focus and exposure are calculated, the shutter (usually a leaf shutter - just like in the old days) closes and the image sensor is "charged". The shutter is opened and the image is sent off to the buffer.

Hence "shutter lag" - yet another reason to dislike "Live View". However, with a SLR - makes not difference whether film or digital - if you see the "perfect" image in the viewfinder - you missed the shot, because the image is captured when the mirror is up and you can't "see" anything.

The Elitist - formerly known as PDL
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, dslr, photography, sensor, shutter

Similar Threads
Thread Thread Starter Forum Replies Last Post
People Mechanical Bull r0ckstarr Post Your Photos! 2 09-23-2010 03:24 PM
Mechanical Support interested_observer Pentax Camera and Field Accessories 2 07-02-2010 11:30 AM
List of Pentax DLSRs equipped with Sony sensor? ducdao Pentax DSLR Discussion 36 07-02-2010 04:19 AM
Why do DSLRs have mechanical shutters? Spock Pentax DSLR Discussion 9 09-18-2009 10:14 AM
Consistency of Mechanical Shutters? zx-m Film SLRs and Compact Film Cameras 3 06-06-2008 02:10 PM



All times are GMT -7. The time now is 07:10 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top