The increasing popularity of Compact System Cameras or CSCs is understandable; they are usually cheaper, smaller, lighter, fully featured, adaptable and generally easier to use all round, so why is the DSLR still relevant to enthusiast photographers?
More specifically, CSCs are indeed on the whole not only considerably smaller than the equivalent DSLR camera, but they also enjoy distinct advantages from having an electronic viewfinder (EVF), as opposed to the more traditional optical viewfinder found in bulkier DSLR cameras.
The EVF however, may not be everyone’s favourite way of viewing the world, (and more on that later), but it does allow such things as information to overlay the viewfinder image. This can include for example: exposure histogram, peaking indicators and image zoom for easier manual focus and zebras which are so useful for showing the highlight limits in video work.
Since there is no mirror to lock up in live view like a DSLR, it also means that the viewfinder is always showing a live feed so unlike a DSLR where you have to use the LCD screen on the back of the camera when in live view or shooting video for example, with the CSC, you can hold the camera to your eye as you shoot video, which is far more natural in run-and-gun video situations. It also means you can shoot video while looking to observers as though you are just shooting stills, which can be very handy in candid or covert situations.
An EVF also means there is no mirror to move at exposure, hence a quieter, (sometimes silent) camera that also suffers from far less vibration; useful in long exposure photography where the slightest shake can spoil the shot.
Fast frame rates are often another advantage of not having a mirror that needs to be moved up and down and CSC cameras, because they have no mirror box, can allow the back of the lens to be closer to the sensor, which in turn can enable a wide range of lenses from other manufacturers to be used via lens/body adaptors.
Mixing and matching different lenses to one camera body can be a lot of fun, as well as being incredibly useful. If for example, you have a range of old lenses from film SLR days that you would like to use on a digital camera, a CSC can make this possible assuming a suitable adaptor can be found.
Alternatively you might have a line of quality lenses from a rangefinder camera that you’d like to use with a through-the-lens focussing camera and a lot of people are doing just that with their Leica M, Voigtlander and Zeiss rangefinder lenses, adapted to fit on modern mirror less cameras, with great success.
So far it’s not looking too good for the DSLR is it! However as mentioned right at the start of this article, the electronic viewfinder is not everyone’s favourite way of viewing the world and in some cases, the optical viewfinder still enjoys some fundamental advantages.
Good as electronic viewfinders are, even the best current EVFs cannot quite match the full range of colours and tones, the true highlights and the deepest shadow details, that one can see with the naked eye through an optical viewfinder. In tricky light situations with extreme highlights or shadows, the EVF is often far from satisfactory.
At this point we probably ought to remind ourselves that DSLR stands for Digital Single-Lens Reflex camera. The ‘Reflex’ part of this equation is what we are interested in because it is the ‘Reflex’ design that by using a mirror to bend light up into our pentaprism viewfinder, which allows light, in all its natural glory, to travel through the lens to our eye; so we see what the lens and sensor will see.
When we view the scene, the mirror sends the image to our viewfinder with all the glorious nuances of real life; no pixels or interpolation involved here, just pure, natural light! In comparison to an EVF, this way of experiencing the world around us, as we compose our masterpiece, is far more intuitive.
The optical viewfinder gives us a magnificent, big, bright and very real view of the world, that cannot be underestimated. For many it is a vital component of a satisfying photographic experience. We are seeing the world as it is, with nothing electronic between us and the scene.
For those that revel in being at one with the surroundings or subject and enjoy the whole compositional process, surely this is central to the real art of photography and here the optical viewfinder is king!
When we make the exposure, the mirror flips up, momentarily blacking out the viewfinder, while the light forming our image is sent to the image sensor, which records the scene. It may sound like a disadvantage, but thanks to the way our eye and brain work in coordination, this blackout effect is neutralised.
In most exposure situations where we are trying to capture life without blur, the time the mirror is up blocking the viewfinder image is miniscule; measured literally in fractions of a second. It is largely imperceptible to the human eye and our brains effectively ignore the tiny interruptions. In effect, we see a completely uninterrupted view of the scene, even while making a sequence of exposures, unless very slow shutter speeds are used.
Here we hit the core of the advantage of the optical viewfinder and hence one of the main reasons why the DSLR is not yet dead! That wonderful optical view is for the most part uninterrupted, which is very important for good reason.
When we are shooting multiple frames at fast shutter speeds following an active wildlife subject or sports for example, we can see and anticipate where the subject is heading without taking our eye from the viewfinder. This is key. When we pan the DSLR, we can follow our subject and (depending on our skills!), keep it centred under the active focus points while the subject may be moving at considerable speed.
This is not the case with every EVF equipped, mirror less CSC that I have reviewed to date. All of them, even the outstanding Samsung NX1 with its vaunted 15 frames per second, interrupt the view of the subject with a series of consecutive briefly frozen still frames.
Even though these frames are displayed very rapidly, it is still not fast enough to keep up with say a bird in flight, where after several still frames, no matter how rapid, you have usually lost the subject out of the frame of view while you were distracted by the last frozen image.
Quite what the technical limitations are for the manufacturers/designers in curing this problem, I can’t quite fathom out. When shooting video, one sees an uninterrupted live view stream, so that surely ought to be possible in stills mode as well, one would think. When I shoot a high speed sequence with my conventional DSLR, I don’t want to view the captured images until I have finished shooting anyway, when I will preview the images on the rear LCD.
Why therefor would anyone want to be previewing shots in a similar high speed sequence with an EVF equipped camera? For my part, I just want the uninterrupted live view stream, I know I am shooting a sequence and the only cue I need is the sound of the shutter operating sequentially. I will preview the images later once the action is over and the images are safely ‘in the can’ as it were.
Still, for whatever reason, that currently doesn’t seem to be possible with any of the EVF equipped cameras I have tried. They all provide a stream of momentarily frozen stills when shooting high frame rates, even when image preview is switched off, which is very confusing for the hand/eye coordinaion required to pan with a fast subject.
For this reason, I’ll stick with the trusty DSLR at the moment, particularly for sport and wildlife action sequences, where that uninterrupted optical view can be the difference between getting the shot, or losing a vital moment of the subject, out of frame, possibly never to be repeated!
So what are the alternatives, if any? Well, there is one camera that I have tried and love very much that might give an inkling of a possible way ahead and that’s the Fujifilm X100T. Like the Fuji Xpro before it, it is the only camera I am aware of that currently pulls off the trick of combining a beautiful optical viewfinder, with an electronic overlay. The X100T also manages to correct the optical view for parallax – amazing! The trouble is, this is a rangefinder style camera with an optical window in the body of the camera which makes life much easier for the designer.
Combining an electronic overlay with an optical path in a reflex camera is going to prove more of a challenge, but it surely isn’t beyond the wit and ingenuity of man in 2015! Perhaps the semi transparent, pellicle mirror, which Sony have been using in the Sony Alpha SLT cameras may offer a potential solution?
I recently tested and reviewed the Sony A77 II SLT, (Single-Lens Translucent), equipped camera which is extremely impressive all round. The primary use of the pellicle mirror in this camera however, has primarily been to provide continuous phase and contrast-detection focusing. The A77 II still has an electronic viewfinder rather than optical one, which seems to almost defeat the main point of having a mirror!
Currently, in many ways however, we are very spoilt for choice. We have some great CSCs with ever increasing capabilities and manufacturers like Canon, Nikon, Sony, Pentax/Ricoh and others are also still producing excellent DSLR cameras, often borrowing useful features from CSCs, like Wi Fi, Tilt and touch screens etc.
For the future? Well who knows, but I suspect that perhaps in the same way that ultra thin materials like graphene are being developed, a light transmitting mirror material could be just around the corner that would be thin enough to allow an uninterrupted light path to the sensor to facilitate a live view overlay in the viewfinder, whilst also providing enough light up into the pentaprism for a true optical viewfinder as the main compositional aid. Now that really would be magic!
Here are a few recent CSC and DSLR reviews I have written that relate to this article: