Why do modern DSLR cameras need a mirror?
Discussion
Am hoping this isn't too dumb a question, but why do modern DSLR cameras actually need a mirror. I appreciate that in the 1980s and 1990s it enabled the photographer to view the image through the viewfinder, but nowadays with the advent of digital technology surely an electronic viewfinder could display what the lens sees, so why continue with the mirror?
I ask this because on a number of occasions each year I take photographs in the local concert hall or theatre, when you can literally hear a pin drop, so the clatter of the mirror moving out of the way when using a DSLR sounds deafening, so I generally wait will till the end of the performance when the audience start applauding. If taking the photo was silent it would make life so much easier. Using my previous S100 and my current RX100 with the sound options switched off is so much easier.
So once again. why do current generation DSLR cameras have a mirror when an electronic viewfinder would solve the problem.
I ask this because on a number of occasions each year I take photographs in the local concert hall or theatre, when you can literally hear a pin drop, so the clatter of the mirror moving out of the way when using a DSLR sounds deafening, so I generally wait will till the end of the performance when the audience start applauding. If taking the photo was silent it would make life so much easier. Using my previous S100 and my current RX100 with the sound options switched off is so much easier.
So once again. why do current generation DSLR cameras have a mirror when an electronic viewfinder would solve the problem.
GravelBen said:
Simpo Two said:
Personally I like to see through the lens, not look at a TV.
+1Most SLRs do have a 'quiet' shutter mode now, which dampens the noise of the mirror. Its still not silent though.
Surely at this point the DSLR is using raw digital data for transferring to the SD card, with the optical viewfinder kept on for namesake rather than for practical reasons.
Perhaps the mirror will indeed be deleted in the next generation of DSLR cameras.
rich888 said:
Surely at this point the DSLR is using raw digital data for transferring to the SD card, with the optical viewfinder kept on for namesake rather than for practical reasons.
Perhaps the mirror will indeed be deleted in the next generation of DSLR cameras.
They won't be DSLRs then! You can if course have an optical VF that doesn't look through the lens - but that method is much older than reflex cameras, so would be going backwards. Perhaps the mirror will indeed be deleted in the next generation of DSLR cameras.
Simpo Two said:
rich888 said:
Surely at this point the DSLR is using raw digital data for transferring to the SD card, with the optical viewfinder kept on for namesake rather than for practical reasons.
Perhaps the mirror will indeed be deleted in the next generation of DSLR cameras.
They won't be DSLRs then! You can if course have an optical VF that doesn't look through the lens - but that method is much older than reflex cameras, so would be going backwards. Perhaps the mirror will indeed be deleted in the next generation of DSLR cameras.
I think the term SLR and DSLR has been retained by manufacturers due to their fear if they do pull the plug on the mirror.
Perhaps the next generation of mirror-less digital cameras is about to be unveiled...
rich888 said:
Yes many manufacturers provide a 'quiet' shutter mode for the mirror, but it's not the mirror in modern day cameras that is collecting the image data, it is the image sensor.
The mirror has never collected image data.If you go back to the days of film there were plenty of mirrorless cameras around. Most did not show you what the lens would record just an approximation. No problems if you got a camera with good parallax compensation except close up. Then you had to be careful to frame the image to the right markings in the viewfinder (if it has any.
If you used other cameras (Like the RollieFlex or RollieCord twin lens systems for example - one lens to view, the other to record the image) the images were inverted. No problem if you got used to it but disconcerting for some - hence the development of the SLR with mirror and prism to provide the user with a image that was easy to relate to.
Go back 10 years to the early EVF implementations and they were pretty dire for anything other than static shots. Things have, reportedly, improved dramatically in the past 2 or 3 years but not without introducing other compromises and using valuable battery power.
Would the theatre allow you to shoot 4K video? That might be the way forward. Alternatively you can get (expensive) sound proofing cases for cameras. Probably a bit OTT for your needs and I'm not sure how readily available they might be these days.
I much prefer to see directly through my relatively high resolution eye rather than a relatively low resolution screen where small details that might influence the choice of critical moment could easily be lost.
rich888 said:
Why is that when DSLR stands for digital single-lens reflex camera and has nothing to do with the mirror because for the vast majority of camera users, the term DSLR is regarded as the best of the best.
The reflex part of DSLR is the mirror though surely? Hence why mirrorless cameras exactly as you describe are simply referred to as 'mirrorless' rather than SLR's. Sony, Olympus and Fuji's line ups all labour heavily on mirrorless cameras in DSLR form with integrated EVF's,
The way technology has progressed, the EVF's are now at a standard where I think few people would say that that element is an issue in itself. Arguably they're now better than an optical view finder.
The one area where mirrorless still seems to fall short is tracking auto focus. I don't know the complexities of how the systems work but obviously SLR's cannot use the sensor for AF when the mirror is down, so they have an additional AF system. Mirrorless cameras use the sensor just as live view would on a DSLR. Focus acquisition is lightning fast on some recent mirrorless cameras but I'm yet to use one that can track moving subjects with anything like the accuracy of a good (or even average) DSLR. I think once that last box is ticked, I'll make the jump.
rich888 said:
I ask this because on a number of occasions each year I take photographs in the local concert hall or theatre, when you can literally hear a pin drop, so the clatter of the mirror moving out of the way when using a DSLR sounds deafening, so I generally wait will till the end of the performance when the audience start applauding. If taking the photo was silent it would make life so much easier.
.
rich888 said:
Why is that when DSLR stands for digital single-lens reflex camera and has nothing to do with the mirror...
Note what the 'R' in DSLR stands for, and what it refers to:http://en.wikipedia.org/wiki/Digital_single-lens_r...
I'm not following the need to use an SLR (D, or otherwise) in the setup the OP describes.
It sounds like the perfect job for a mirrorless camera. For Canon users, something like the Canon EOS-M would let you use all the normal glass you currently use, with a sensor the same as the 7D.
Ok, you have to look at screen rather than through a viewfinder and you have the obvious compromises with AF etc but if you must be silent, what other options do you have?
I was recently in a stage production and the photog came on the dress rehearsal night and I have to say I found it massively off putting hearing the AF beep followed by the "CH-CKKK" of the shot being taken and was very aware of it onstage.
Accepting that a DSLR by definition will have a mirror, why not use a mirrorless OP?
It sounds like the perfect job for a mirrorless camera. For Canon users, something like the Canon EOS-M would let you use all the normal glass you currently use, with a sensor the same as the 7D.
Ok, you have to look at screen rather than through a viewfinder and you have the obvious compromises with AF etc but if you must be silent, what other options do you have?
I was recently in a stage production and the photog came on the dress rehearsal night and I have to say I found it massively off putting hearing the AF beep followed by the "CH-CKKK" of the shot being taken and was very aware of it onstage.
Accepting that a DSLR by definition will have a mirror, why not use a mirrorless OP?
Personally I'm old fashioned and prefer taking photos using the optical view finder than any electric viewfinder or the LCD screen.
More practically the mirror is also needed to divert the image onto the Auto Focusing 'Chip' for Phase Detection AF. This means the camera can focus very quickly and exactly on the subject in question, so that when you hit the trigger your capture what you see.
Most 'mirror-less' cameras use Contrast Detection AF, which is slow and not as reliable, though Cannon's new hybrid sensor can do both without needing a Auto Focusing chip, but am not-sure how quick the Phase detection AF in live view is compared to using the optical view finder. It will be interesting to see how live view performs in the new 7D mark II, given its major selling point is it's amazing AF system, which I persume you loss if you use it in live view all the time?
The annoying 'bleep' can be easily turned off, as for the shutter noises, personally I love it, but than again I'm old fashioned when it comes to cameras, and still remember the days of having to process film, and rewind the film with your self
More practically the mirror is also needed to divert the image onto the Auto Focusing 'Chip' for Phase Detection AF. This means the camera can focus very quickly and exactly on the subject in question, so that when you hit the trigger your capture what you see.
Most 'mirror-less' cameras use Contrast Detection AF, which is slow and not as reliable, though Cannon's new hybrid sensor can do both without needing a Auto Focusing chip, but am not-sure how quick the Phase detection AF in live view is compared to using the optical view finder. It will be interesting to see how live view performs in the new 7D mark II, given its major selling point is it's amazing AF system, which I persume you loss if you use it in live view all the time?
The annoying 'bleep' can be easily turned off, as for the shutter noises, personally I love it, but than again I'm old fashioned when it comes to cameras, and still remember the days of having to process film, and rewind the film with your self
Edited by gangzoom on Monday 17th November 13:44
Firstly, mirrorless cameras do exist and not just at the cheap end of the market. You can spend £1500+ on a Sony A7R which will match or beat the top end DSLRs for image quality.
The reasons that DSLRs still dominate the professional market are mainly down to the compromises that removing the mirror entail; Having to run the sensor continuously drains the battery MUCH faster, light can no-longer be diverted to separate auto-focus systems and electronic viewfinders can struggle in certain situations such as low-light or fast action.
If you switch a DSLR to live-view it essentially achieves many of the same advantages. Completely silent shutter, live image preview and contrast detection autofocus are all available at the flick of a switch. The only things they can't match mirrorless cameras on are size/weight and the ability to use non-native lenses; things which are not very relevant in a professional context.
The reasons that DSLRs still dominate the professional market are mainly down to the compromises that removing the mirror entail; Having to run the sensor continuously drains the battery MUCH faster, light can no-longer be diverted to separate auto-focus systems and electronic viewfinders can struggle in certain situations such as low-light or fast action.
If you switch a DSLR to live-view it essentially achieves many of the same advantages. Completely silent shutter, live image preview and contrast detection autofocus are all available at the flick of a switch. The only things they can't match mirrorless cameras on are size/weight and the ability to use non-native lenses; things which are not very relevant in a professional context.
I'm prepared to be convinced otherwise, but there's very little that beats the Mk.1 eyeball for resolution or dynamic range. An optical through the lens viewfinder allows you to use that eyeball to calibrate what you're seeing - and what you want to be able to see in the exposed image. An electronic viewfinder dramatically reduces your ability to do that.
How many times have you taken a photo that looks great on the camera screen only to find that when you look at it on a monitor it's just a little bit out?
How many times have you taken a photo that looks great on the camera screen only to find that when you look at it on a monitor it's just a little bit out?
Tuna said:
I'm prepared to be convinced otherwise, but there's very little that beats the Mk.1 eyeball for resolution or dynamic range. An optical through the lens viewfinder allows you to use that eyeball to calibrate what you're seeing - and what you want to be able to see in the exposed image. An electronic viewfinder dramatically reduces your ability to do that.
How many times have you taken a photo that looks great on the camera screen only to find that when you look at it on a monitor it's just a little bit out?
There are two opposing views on that. Some people want to see the scene in front of them, others prefer to see a preview of the finished image. The first group prefer optical finders, the latter prefer LCD screens (either EVF or on the back of the camera).How many times have you taken a photo that looks great on the camera screen only to find that when you look at it on a monitor it's just a little bit out?
Mr Will said:
There are two opposing views on that. Some people want to see the scene in front of them, others prefer to see a preview of the finished image. The first group prefer optical finders, the latter prefer LCD screens (either EVF or on the back of the camera).
The "finished image" approach implies (not necessarily correctly) that people are shooting to jpg. Great if you have good light and "bright" locations - i.e. colourful, balanced dynamic range in play, etc. Not so good if you don't and will need to work on the image later.That sais I don't think this is an either/or situation. There is no reason to restrict oneself to a single choice especially in an age when lenses (an expense of significant proportions in anyone's view) can often be shared across lens mounts using adapters thus reducing the costs of working wiht different systems.
Mr Will said:
There are two opposing views on that. Some people want to see the scene in front of them, others prefer to see a preview of the finished image. The first group prefer optical finders, the latter prefer LCD screens (either EVF or on the back of the camera).
The "finished image" approach implies (not necessarily correctly) that people are shooting to jpg. Great if you have good light and "bright" locations - i.e. colourful, balanced dynamic range in play, etc. Not so good if you don't and will need to work on the image later.That said I don't think this is an either/or situation. There is no reason to restrict oneself to a single choice especially in an age when lenses (an expense of significant proportions in anyone's view) can often be shared across lens mounts using adapters thus reducing the costs of working with different systems.
Gassing Station | Photography & Video | Top of Page | What's New | My Stuff