Eyes in the dark
Darkness is a common failure of LCDs and EVFs. This seems obvious because night-photography requires exposures of several seconds or even minutes. Since a camera's sensor is read every fraction of a second to produce the view on the LCD, it does not have time to accumulate sufficient light to produce a comfortable preview. Sadly this is the case of most LCDs and EVFs on cameras available today.
To allow the use of LCDs and EVFs in the dark, a few companies have implemented a system which amplifies the sensor's output to produce a brighter preview. The one company that has managed this far better than all others is Konica-Minolta. Several of its prosumer digital cameras amplify the brightness of their displays and, in very low light, turn the previewed image into a monochrome image (black and white images have higher contrast than color images). This corresponds well to the behavior of the human eye in low-light because low-light sensors in our eyes are achromatic (they don't see colors).
As for optical viewfinders, they are ideal for low-light photography because our eyes adapt well to low levels of lighting. This is done in part by using sensors which are very sensitive to light but not sensitive to colors.
Of all the types of viewfinders, the LCD is the only one which is positioned differently. While it may not seem important, those who have frequently used an LCD for composing a picture will disagree. Precisely framing a picture using an LCD is more difficult than with any other type of viewfinder. This occurs because when using other viewfinders the photographer is looking from (or close to) the point of view of the camera. It is easy to frame this way because we are almost seeing the picture. When using an LCD, what we see is an LCD which is showing a picture. Most people who frame using an LCD complain about having difficulty keeping the horizon horizontal. Some digital cameras optionally overlay a grid to help keeping the camera level. Most LCDs exhibit another problem: difficulty to see in bright light. Since LCDs are open to ambient light, they can reflect light which makes the image almost impossible to make out. An anti-reflective coating on an LCD can diminish that problem. Some LCDs reflect ambient light from behind the display which greatly diminishes the problem. Such LCDs are called transreflective displays. Only a few camera models have trasreflective LCDs.
The position and size of LCD displays provide a unique advantage among viewfinders: an LCD can be seen without having the camera right against our eye. Although it was mentioned earlier that this makes framing more difficult, some shots may not be possible to frame using any other type of viewfinder. Indeed poor framing is better than no framing. After a picture is taken its framing can be possibly improved by cropping. Rotational corrections however damage the quality of digital pictures, so it is most important to keep shots level. Many cameras are equipped with LCDs which can be moved and rotated in various ways which augment framing possibilities: overhead shots, ground level shots, self portraits, etc.
The length alone of this article demonstrates that issues surrounding viewfinders are numerous. Each type of viewfinder has its advantages and each type has its disadvantages. For those who have been keeping score, it seems that EVFs and SLR viewfinders have the most advantages. The principal trade-off between the two is exposure preview versus precision. Most photographers will prefer SLR viewfinders because that is what they are used to. Photographers from the film days have all gotten used to not being able to preview exposure.
Choosing a viewfinder can't be done without choosing a camera. This is where choice becomes compromise. Digital SLR cameras all have SLR viewfinders, by definition. They also have an LCD but not for preview. Long zoom (6X or more) fixed lens digital cameras all have EVFs, so do very wide angle fixed lens cameras. There was a fixed lens digital SLR by HP, but it has been long discontinued. In the end, the needs of a photographer will dictate the type of camera he uses. This choice will then dictate the types of viewfinders available. Only then will knowing how each type of viewfinder works help a photographer choose a specific camera. For a photographer the experience given by a viewfinder is important, unfortunately the choice is not completely up to him.
Neocamera Blog is a medium for expressing ideas related to digital cameras and photography. Read about digital cameras in the context of technology, media, art and the world. Latest posts links:
Nikon D5 XQD Review
Nikon flagship professional DSLR with 20 megapixels Full-Frame CMOS sensor. All-new 153-point Phase-Detect AF sensitive to -4 EV. ISO 50 to unprecedented 3,276,800! 12 FPS Drive for 200 JPEGs or 180 RAW. First Nikon DSLR with 4K Ultra HD video.
Olympus Professional Lens Roundup
Roundup of Olympus Professional and Premium lenses: M.Zuiko 7-14mm F/2.8 PRO, M.Zuiko 12-40mm F/2.8 PRO, M.Zuiko 40-150mm F/2.8 PRO, M.Zuiko 12mm F/2, M.Zuiko 60mm F/2.8 Macro.
Olympus OM-D E-M10 Mark II Review
Olympus second generation base OM-D with an anti-alias-filter-free 16 MP Four-Thirds CMOS sensor mounted on a 5-axis in-body stabilization system. Speedy 8.5 FPS drive, full HD @ 60 FPS and a wealth of features in a compact and lightweight body. Offers a 2.4 MP 0.45" EVF with 0.62X magnification and 100% coverage, plus dual control-dials and a highly customizable interface.
Fuji X-Pro2 Review
Fuji flagship XF-mount mirrorless with 24 MP APS-C X-Trans CMOS III sensor. 273-Point AF with 169 Phase-Detect points. 8 FPS Drive, 1080p video. Dual control-dials, direct dials and a hybrid viewfinder in a weather-sealed freezeproof body.
Panasonic Lumix DMC-ZS100 Review
The only premium travel-zoom! 20 megapixels 1" high-speed CMOS sensor paired with a stabilized 25-250mm F/2.8-5.9 optical zoom. 50 FPS Drive, 4K Ultra-HD video, 1/16000-60s Hybrid Shutter, Post-Shot Focus, 4K Live-Cropping, Time-Lapse Video and more. Dual control-dials plus a built-in EVF with Eye-Start sensor.
Canon EOS Rebel T6s Review
Newly designed Rebel with dual control-dials and top status LCD. 24 MP APS-C sensor, Hybrid AF III with 19 all-cross points and on-sensor Phase-Detect AF. 5 FPS Drive and full 1080p HD video capture.
Canon Powershot G3 X Review
Ultra-zoom with a 25X optical zoom lens and large 20 MP 1" CMOS sensor in a weather-sealed body with dual control-dials, a lens ring and efficient controls. Captures full 1080p HD video at 60 FPS with internal or external stereo sound.
Best Digital Cameras of 2015
The best new digital cameras of 2015. Plus, find out which ones of 2014 still lead their category. Compact, Premium Cameras, Ultra-Zooms, Mirrorless and DSLR are all covered.
Panasonic Lumix DMC-G7 Review
16 megapixels Micro Four-Thirds mirrorless. 2.4 MP 0.5" EVF with Eye-Start sensor plus dual control-dials. 4K Ultra-HD video, 8 FPS continuous-drive, hybrid shutter with 1/16000-60s shutter-speeds, ISO 100-25600 and Contrast-Detect DFD autofocus system sensitive to -4 EV.
Nikkor AF-S 200-500mm F/5.6E ED VR Review
Nikon constant-aperture super-telephoto zoom with 200-500mm range and the latest Vibration-Reduction effective to 4.5 stops. Built-in super-sonic AF in a sturdy weatherproof body.