Why mechanical shutter on dslr?

[Garbz]

Not familiar with Nikon.. why did they stop doing that?

There are several downsides to having an electronic shutter. One was mentioned above and that is that readout occurs across the sensor called a rolling shutter. In extreme cases this could make the results of the picture look like the slow focal plane shutters of the 60s distorting moving images. This one can be worked around through the use of a global shutter, but the last CMOS sensor I saw implementing a global shutter without sacrificing performance cost just upwards for $10k. CCDs on the other hand could very easily be read out globally as the name implies, "Charge Coupled" meaning the image is not read out from the same part which records the light. Their issue though is when the the charge is transferred and light still falls on the sensor you end up with horrendous smear or blooming.

So in either technologies a mechanical device we have more than 60 years experience with does the trick.

I was just thinking why DSLRs use mechanical shutter and are limited to shutter sync speed for flash photography. Can't they just turn the sensor on and off to whatever shutter speed you want? I apologize if this is a stupid question.

Isn't that just what P&S cameras do? I thought the main problem with an electronic "sensor on/off" system was shutter lag.

Lag is introduced on CMOS cameras. Many P&S have CCDs. The lag was just the result of outright ****ty performance. For the most part many P&S have very little actual shutter lag but were horrendously slow at powering on, focusing, readout, displaying the image, not to mention that they needed to first close the shutter and turn off liveview. Also ever notice that many P&S cameras suffered bloom in liveview but not in the final image? You'd be amazed how many of them actually had rudimentary mechanical shutters if for nothing else than to read out the data from the sensor. See D70, D40, Canon 1D for examples of cameras which used electronic shutters but negligible lag. But see above for a reason why it's bad.

Nikon d70 is old but will give you unlimited sync speed due to it's electronic shutter

Not quite unlimited. They limit it to 1/500th or 1/1000th from what I remember due to efficiency reasons. In theory the sensor can read out at a shutter speed faster than the time a flash bulb is on when fired at full power, so if you go above 1/1000th you start getting bizarre power characteristics from your flash.

 

[Destin]

There are several downsides to having an electronic shutter. One was mentioned above and that is that readout occurs across the sensor called a rolling shutter. In extreme cases this could make the results of the picture look like the slow focal plane shutters of the 60s distorting moving images. This one can be worked around through the use of a global shutter, but the last CMOS sensor I saw implementing a global shutter without sacrificing performance cost just upwards for $10k. CCDs on the other hand could very easily be read out globally as the name implies, "Charge Coupled" meaning the image is not read out from the same part which records the light. Their issue though is when the the charge is transferred and light still falls on the sensor you end up with horrendous smear or blooming.

So in either technologies a mechanical device we have more than 60 years experience with does the trick.

Lag is introduced on CMOS cameras. Many P&S have CCDs. The lag was just the result of outright ****ty performance. For the most part many P&S have very little actual shutter lag but were horrendously slow at powering on, focusing, readout, displaying the image, not to mention that they needed to first close the shutter and turn off liveview. Also ever notice that many P&S cameras suffered bloom in liveview but not in the final image? You'd be amazed how many of them actually had rudimentary mechanical shutters if for nothing else than to read out the data from the sensor. See D70, D40, Canon 1D for examples of cameras which used electronic shutters but negligible lag. But see above for a reason why it's bad.

Not quite unlimited. They limit it to 1/500th or 1/1000th from what I remember due to efficiency reasons. In theory the sensor can read out at a shutter speed faster than the time a flash bulb is on when fired at full power, so if you go above 1/1000th you start getting bizarre power characteristics from your flash.

Unless, as mentioned, you have dumb speedlights. I use lots of manual OCF, and therefore was able to use shutter speeds up to 1/4000th of a second alot of the time with my old d70. I'm thinking about picking up another d70 (they're DIRT cheap) just to have for situations like that.

 

[table1349]

Electronic isn't always better. The common electro/mechanical shutter is easy to build, easy to install, easy to adjust, easy to repair and easy to replace at a lower cost than a sensor. Lose a electro/mechanical shutter and have it replaced you have the same sensor producing the same results. Replace the sensor and it's rendition of color may be off from what you are used too.

It's kind of like a car. You tires are worn out. Do you really need to replace the entire drive train, or just the tires?

 

[Crollo]

Teribly sorry to be that guy that just has to bump that old thread, but... Are there people seriously arguing the advantages of OVF vs EVF over the SHUTTER? We're discussing the SHUTTER TYPE, not the mirror.

 

[Sw1tchFX]

Because when you have electronic shutters, this happens:

Also, unless you want to use CCD's again, CMOS sensors can't do global shutters because they read the sensor from the top-down instead of all at once like a CCD.

 

[gsgary]

Not familiar with Nikon.. why did they stop doing that?

My 1Dmk1 will sinc at 1/500 and so will my Mamiya

 

[kassad]

I can understand the arguments of ccd vs cmos, but why can't they make specialty lenses with a leaf shutter like are available in medium formats? I would think if they offered a portrait lens with a leaf shutter option there would be enough demand to justify development.

 

[Overread14 2]

The problem might be that introducing the leaf shutter into their lenses would increase lens development, design and production costs and, as a result, drive the lens prices higher still than they already are. What with the recession hitting many of their target market and rises in prices of raw materials (to say nothing of the disaster in Japan) they might feel that further rising of the price of their lenses would not be suitable for their primary target market.

 

[kassad]

The problem might be that introducing the leaf shutter into their lenses would increase lens development, design and production costs and, as a result, drive the lens prices higher still than they already are. What with the recession hitting many of their target market and rises in prices of raw materials (to say nothing of the disaster in Japan) they might feel that further rising of the price of their lenses would not be suitable for their primary target market.

I hear what your saying but Canon didn't hesitate in bumping the price of the 24-70 2.8 almost $1000. That's not even a new type of lens that's an upgrade to an existing lens. If Mamiya can sell a 80mm 2.8 leaf shutter lens for $2500 to a tiny specialised market I would think Canon could sell and similar lens to a much larger market at either a lower price or faster aperture. Heck they would be able to sell it with the same specs and price and it wouldn't compete with the 85mm F1.2 which is retailing for only $300 less.

 

[gsgary]

Phase One with right will sinc with right lens at 1/1600 or it cold be 1/16000 will have to check

 

[Overread14 2]

I'd think 1/1600 - 1/16000 sounds insane for a sync speed and closer to what I'd be expecting from specialist gear (of course saying that Phase One IS specialist gear - just not the kind I'd expect to see such a speed from).

 

[table1349]

I can understand the arguments of ccd vs cmos, but why can't they make specialty lenses with a leaf shutter like are available in medium formats? I would think if they offered a portrait lens with a leaf shutter option there would be enough demand to justify development.

Simple answer, they can. Reality, no reason to reinvent the wheel. Not enough gain for the costs.

 

[gsgary]

I'd think 1/1600 - 1/16000 sounds insane for a sync speed and closer to what I'd be expecting from specialist gear (of course saying that Phase One IS specialist gear - just not the kind I'd expect to see such a speed from).

Checked 1/1600