is the mirror in the DSLR there just so that you can use the viewfinder?

[BlahBlahYouToo]

if so, and you did not need/want the viewfinder, you technically could engineer a camera of comparable image quality (due to the higher quality and sized sensor) to not need the mirror mechanism, correct?

just use the LCD to frame the image, snap the shot and expose the image directly to the sensor?
or is there another function for the mirror?

<--- does not own a DSLR yet

 

[twistedlogic]

Yeah, they are called mirrorless cameras.

Canon/Nikon have yet to introduce one.

 

[JohnnyRebel]

if so, and you did not need/want the viewfinder, you technically could engineer a camera of comparable image quality (due to the higher quality and sized sensor) to not need the mirror mechanism, correct?

just use the LCD to frame the image, snap the shot and expose the image directly to the sensor?
or is there another function for the mirror?

<--- does not own a DSLR yet

The Mirror lets you see thru the lens you are using in real time. Rangefinders do not look thru the lens. Using the LCD image to shoot puts you slighty behind the actual shot.

JR

 

[BlahBlahYouToo]

The Mirror lets you see thru the lens you are using in real time. Rangefinders do not look thru the lens. Using the LCD image to shoot puts you slighty behind the actual shot.

JR

so what you're saying is latency the reason to use the mirror over an LCD system.

 

[Sp12]

It's one of them. There are advantages and disadvantages to both, and you could probably find articles and articles about it from the forum drama that came up when camera makers introduced live-view for DSLRs.

 

[AkumaX]

It's one of them. There are advantages and disadvantages to both, and you could probably find articles and articles about it from the forum drama that came up when camera makers introduced live-view for DSLRs.

And why Sony's implementation is quite unique.

P.S. OP is banned?

 

[BlahBlahYouToo]

And why Sony's implementation is quite unique.

P.S. OP is banned?

yeah, but i hacked my way back in.
mods got nothing on me.

 

[bobdole369]

Look up Live View. The tech needed to process and display 10-15MP of information is not trivial. Its simpler to add in a mirror and viewfinder to give you an actual "what you see is what you get" through the lens.

 

[ElFenix]

the mirror is integral to the auto focus system on SLRs. behind that mirror you can see is another mirror that bounces light into the focus system on the floor of the chamber.

 

[RampantAndroid]

the mirror is integral to the auto focus system on SLRs. behind that mirror you can see is another mirror that bounces light into the focus system on the floor of the chamber.

Yes, this - flip the mirror up slowly and you will see the second mirror.

I don't WANT an LCD to use as the viewfinder...I prefer straight up optics. Only delay I want to see is one caused by the speed of light

Also...LCDs with a high enough pixel pitch to display what you see at any size are pretty expensive. A mirror system I imagine helps keep the cost down. Moving a mirror up when the shutter opens is far less painful than attaching an LCD (and also, adding an LCD means further drain on the battery.)

 

[Griffinhart]

if so, and you did not need/want the viewfinder, you technically could engineer a camera of comparable image quality (due to the higher quality and sized sensor) to not need the mirror mechanism, correct?

just use the LCD to frame the image, snap the shot and expose the image directly to the sensor?
or is there another function for the mirror?

<--- does not own a DSLR yet

My Nikon D90 has a live view feature like this. I can frame the shot on the LCD.

That said, I rarely use that feature. It really drops battery life significantly and I find that in lower light situations, it's much easier to steady the camera the traditional way as I can keep my arms close to my body. I also find it easier to quickly frame and shoot through the viewfinder than I do through the LCD.

It is handy to have from time to time though, when you have to hold the camera above your eye level or above someones head to catch a shot you would otherwise miss.

 

[Cattykit]

By LCD, I assume you're referring to the LCD screen that sits on the backside of a camera. I, too, do not like using that LCD to frame shots but EVF is a different story. I think EVF has a great potential and since I started shooting video, I'm all for EVF. The only problem is that there's no decent EVF solution yet. Rumor has it upcoming Sony A77 will use 3MP OLED EVF. I have high hopes for that one.

 

[corkyg]

No, the mirror is not there just so you can use the viewfinder. Take the "D" out of the acronym and you have SLR. That is, Single Lens Reflex. The primary purpose of the mirror is to enable the photographer to frame and focus through the actual lens of the camera. The "D" simply adds a digital sensor in place of film.

My first 35mm SLR was about 1962 - a Minolta. It replaced a rangefinder 35mm.

It is good to know the history of the SLR in order to appreciate the DSLR.

http://en.wikipedia.org/wiki/History_of_the_single-lens_reflex_camera

I have now had 4 DSLR cameras, current one, a Canon EOS 5D. I only use the rear LCD screen to show someone a picture. The "Live View" feature is nice, but as a photographer, I prefer looking through the lens optically. The mirror system, well described by El Fenix, makes it work just as it has for about 50 years!