Live preview
Encyclopedia
Digital camera
A digital camera is a camera that takes video or still photographs, or both, digitally by recording images via an electronic image sensor. It is the main device used in the field of digital photography...
display screen to be used as a viewfinder
Viewfinder
In photography, a viewfinder is what the photographer looks through to compose, and in many cases to focus, the picture. Most viewfinders are separate, and suffer parallax, while the single-lens reflex camera lets the viewfinder use the main optical system. Viewfinders are used in many cameras of...
. This provides a means of previewing framing and other exposure before taking the photograph
Digital photography
Digital photography is a form of photography that uses an array of light sensitive sensors to capture the image focused by the lens, as opposed to an exposure on light sensitive film...
. In most such cameras, the preview is generated by means of continuously and directly projecting the image formed by the lens onto the main image sensor
Image sensor
An image sensor is a device that converts an optical image into an electronic signal. It is used mostly in digital cameras and other imaging devices...
. This in turn feeds the electronic screen with the live preview image. The electronic screen can be either a liquid crystal display (LCD)
Liquid crystal display
A liquid crystal display is a flat panel display, electronic visual display, or video display that uses the light modulating properties of liquid crystals . LCs do not emit light directly....
or an electronic viewfinder (EVF)
Electronic viewfinder
An electronic viewfinder or EVF is a viewfinder where the image captured by the lens is projected electronically onto a miniature display. The image on this display is used to assist in aiming the camera at the scene to be photographed.-Operation:...
.
Background
The concept for cameras with live preview largely derives from electronic (videoVideo
Video is the technology of electronically capturing, recording, processing, storing, transmitting, and reconstructing a sequence of still images representing scenes in motion.- History :...
) TV cameras
Professional video camera
A professional video camera is a high-end device for creating electronic moving images...
. Until 1995 most digital cameras did not have live preview, and it was more than ten years after this that the higher end digital single-lens reflex cameras (DSLR)
Digital single-lens reflex camera
Most digital single-lens reflex cameras are digital cameras that use a mechanical mirror system and pentaprism to direct light from the lens to an optical viewfinder on the back of the camera....
adopted this feature, as it is fundamentally incompatible with the swinging-mirror single-lens reflex mechanism.
The first digital still cameras with an LCD display and live preview were the Casio
Casio
is a multinational electronic devices manufacturing company founded in 1946, with its headquarters in Shibuya, Tokyo, Japan. Casio is best known for its electronic products, such as calculators, audio equipment, PDAs, cameras, musical instruments, and watches...
QV-10 and Ricoh
Ricoh
or Ricoh, is a Japanese company that was established in 1936 on February 6th, as , a company in the RIKEN zaibatsu. Its headquarters is located in Ricoh Building in Chūō, Tokyo....
RDC-1 in 1995. The first prosumer
Prosumer
Prosumer is a portmanteau formed by contracting either the word professional or less often, producer with the word consumer. For example, a prosumer grade digital camera is a "cross" between consumer grade and professional grade...
camera to use live view for both exposure control and preview framing was the fixed-lens Canon PowerShot G1 from 2000, although this was still in the line of compact cameras.
The first DSLR to use live view for framing preview only was the fixed-lens Olympus E-10
Olympus E-10
The Olympus E-10 is a digital single-lens reflex with a 4.0 megapixel CCD image sensor that was introduced in 2000. Unlike most digital SLRs the camera is not a system camera – its lens is fixed to the body. It has a TTL optical viewfinder, and a 4× optical zoom lens with lens aperture f/2–2.4...
from 2000. The first interchangeable-lens DSLR to use a live preview was the Fujifilm FinePix S3 Pro
FinePix S3 Pro
The Fujifilm FinePix S3 Pro is an interchangeable lens digital single-lens reflex camera introduced in February 2004. Its successor, the Finepix S5 Pro, was released on 25 September 2006...
, which was launched in October 2004. Its "Live Image" mode could display a live, black-and-white preview of the subject that could be magnified for manual focusing purposes, although the preview was limited to a duration of thirty seconds. It was followed in early 2005 by the Canon EOS 20Da, a special version of the Canon EOS 20D
Canon EOS 20D
The Canon EOS 20D is an 8.2-megapixel semi-professional digital single-lens reflex camera, initially announced on August 19, 2004 at a recommended retail price of US$1,499. It is the successor of the EOS 10D, and was succeeded by the EOS 30D in August 2006...
with modifications for astrophotography
Astrophotography
Astrophotography is a specialized type of photography that entails recording images of astronomical objects and large areas of the night sky. The first photographs of an astronomical object were taken in the 1840s, but it was not until the late 19th century that advances in technology allowed for...
, which included a similar focus preview feature. The first general-use interchangeable-lens DSLR with live view for framing preview only was the Olympus E-330
Olympus E-330
The Olympus E-330 is a DSLR launched on 30 January 2006, using the Four Thirds System lens mount standard. Its main feature is its live image preview functionality, permitting an image to be previewed on the LCD screen. While live image preview is not new in compact digital cameras, the E-330 is...
of 2006. The first general-use interchangeable-lens DSLRs with live view for both exposure simulated preview and framing preview were the Canon EOS 1Ds Mark III and Canon EOS 40D
Canon EOS 40D
The Canon EOS 40D is a 10.1-megapixel semi-professional digital single-lens reflex camera. It was initially announced on August 20, 2007 and was released at the end of that month. It is the successor of the Canon EOS 30D, and is succeeded by the EOS 50D. It can accept EF and EF-S lenses...
of 2007.
Types
There are two distinct modes of live-preview, with only a few manufacturers offering both in their digital cameras.The first is a more rudimentary type of live preview that displays the overall framing on an electronic display and allows a preview of what the camera's sensor will detect before the photograph
Photograph
A photograph is an image created by light falling on a light-sensitive surface, usually photographic film or an electronic imager such as a CCD or a CMOS chip. Most photographs are created using a camera, which uses a lens to focus the scene's visible wavelengths of light into a reproduction of...
is taken. This can be particularly helpful when the lighting conditions are too dark for an optical viewfinder. This type of live preview is the autogain/framing live view type (or framing priority display). This requires traditional means of exposure
Exposure (photography)
In photography, exposure is the total amount of light allowed to fall on the photographic medium during the process of taking a photograph. Exposure is measured in lux seconds, and can be computed from exposure value and scene luminance over a specified area.In photographic jargon, an exposure...
determination requiring metering of the light coming through the lens, and interpreting the light intensity
Light intensity
Several measures of light are commonly known as intensity. These are obtained by dividing either a power or a luminous flux by a solid angle, a planar area, or a combination of the two...
indication on an automatic light meter
Light meter
A light meter is a device used to measure the amount of light. In photography, a light meter is often used to determine the proper exposure for a photograph...
, and then adjusting exposure parameters for a desired effect.
The second is a more sophisticated type of live preview that displays the exact exposure 'look' on an electronic display and allows the photographer to alter the exposure look via adjustments to parameters such as shutter speed
Shutter speed
In photography, shutter speed is a common term used to discuss exposure time, the effective length of time a camera's shutter is open....
, film speed or ISO
Film speed
Film speed is the measure of a photographic film's sensitivity to light, determined by sensitometry and measured on various numerical scales, the most recent being the ISO system....
, and aperture
Aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...
, before the photograph is taken. This second type of live preview is the exposure simulation live preview type (or exposure priority display). This type of live preview eliminates reliance on traditional light metering usage.
Many modern bridge and compact cameras with movie mode have only an automatic exposure and limited exposure compensation
Exposure compensation
Exposure compensation is a technique for adjusting the exposure indicated by a photographic exposure meter, in consideration of factors that may cause the indicated exposure to result in a less-than-optimal image. Factors considered may include unusual lighting distribution, variations within a...
control, and live view that is primarily for framing only.
Live preview only cameras
Live-preview-only cameras, that is cameras without an optical viewfinderViewfinder
In photography, a viewfinder is what the photographer looks through to compose, and in many cases to focus, the picture. Most viewfinders are separate, and suffer parallax, while the single-lens reflex camera lets the viewfinder use the main optical system. Viewfinders are used in many cameras of...
, include three different categories: Compact digital cameras, bridge digital camera
Bridge digital camera
Bridge cameras are cameras which fill the niche between the single-lens reflex cameras and the Point-and-shoot camera. They are often comparable in size and weight to the smallest Digital SLRs , but almost all digital bridge cameras lack an optical viewfinder system...
s, and the newer mirrorless interchangeable lens camera
Mirrorless interchangeable lens camera
A mirrorless interchangeable-lens camera is an emerging class of digital system cameras, intermediate between compact digital cameras and digital single-lens reflex cameras . They are characterized by a no-mirror design and an interchangeable lens mount...
s.
Bridge cameras in general are higher-end, that is they contain more advanced features, better build quality, larger size, and are more expensive than compacts, but retain a small digital sensor. Mirrorless cameras feature a larger sensor and interchangeable lenses, like DSLRs, but sacrifice the SLR mirror mechanism and viewfinder to save size and cost, and hence only offer live preview.
Digital SLRs
Live preview in DSLRs does not typically serve as their principal means of framing and previewing before taking a photograph, with this function still being mainly performed with optical viewfinder. The first DSLR to feature live preview was the 2004 FujifilmFujifilm
is a multinational photography and imaging company headquartered in Tokyo, Japan.Fujifilm's principal activities are the development, production, sale and servicing of color photographic film, digital cameras, photofinishing equipment, color paper, photofinishing chemicals, medical imaging...
FinePix S3 Pro
FinePix S3 Pro
The Fujifilm FinePix S3 Pro is an interchangeable lens digital single-lens reflex camera introduced in February 2004. Its successor, the Finepix S5 Pro, was released on 25 September 2006...
.
While initially largely a novelty feature, live-preview functionality has become more common on DSLR cameras, and almost all new DSLRs have had the feature since mid-2008. This is particularly the case since the advent of movie mode features on these cameras.
The following is a partial list of DSLRs with live preview:
- Canon: 20Da, 40DCanon EOS 40DThe Canon EOS 40D is a 10.1-megapixel semi-professional digital single-lens reflex camera. It was initially announced on August 20, 2007 and was released at the end of that month. It is the successor of the Canon EOS 30D, and is succeeded by the EOS 50D. It can accept EF and EF-S lenses...
, 50DCanon EOS 50DThe Canon EOS 50D is a 15.1-megapixel digital single-lens reflex camera. It is part of the Canon EOS line of cameras and succeeds the EOS 40D. In turn, it has been succeeded by the EOS 60D....
, 450DCanon EOS 450DThe EOS 450D is a 12.2-megapixel digital single-lens reflex camera that is part of the Canon EOS line of cameras. It is the successor to the EOS 400D/Digital Rebel XTi. It was announced on the 23 January 2008 and released in March 2008 and April 2008 in North America...
, 500DCanon EOS 500DThe Canon EOS 500D is a 15.1 megapixel digital single-lens reflex camera, announced by Canon on 25 March, 2009. It was released in May 2009. It is known as the EOS Kiss X3 in Japan, and as the EOS Rebel T1i in North America...
, 550DCanon EOS 550DThe Canon EOS 550D is an 18.0 megapixel digital single-lens reflex camera, announced by Canon on February 8, 2010. It was made available starting February 24, 2010 and to US dealers starting early March. It is known as the EOS Kiss X4 in Japan, and as the EOS Rebel T2i in North America...
, 600DCanon EOS 600DThe Canon EOS 600D is an 18.0 megapixel digital single-lens reflex camera, released by Canon on February 7, 2011. It is known as the EOS Kiss X5 in Japan and the EOS Rebel T3i in the United States and Canada...
, 1000DCanon EOS 1000DCanon EOS 1000D is a 10.1-megapixel digital single-lens reflex camera announced by Canon on June 10, 2008 and started shipping in mid August of 2008. It is known as the EOS Kiss F in Japan and the EOS Rebel XS in the United States and Canada...
, 1100DCanon EOS 1100DCanon EOS 1100D is a 12.2-megapixel digital single-lens reflex camera announced by Canon on February 7, 2011. It is known as the EOS Kiss X50 in Japan and the EOS Rebel T3 in the United States and Canada. The 1100D is an entry-level DSLR that introduces movie mode to Canon's entry level DSLRs and...
, 1D Mark III, 1Ds Mark III, 5D Mark IICanon EOS 5D Mark IIThe Canon EOS 5D Mark II is a 21.1-megapixel full-frame CMOS digital single-lens reflex camera made by Canon. It succeeds the EOS 5D and was announced on September 17, 2008.-Improvements compared to original EOS 5D:...
, 7DCanon EOS 7DThe Canon EOS 7D is an 18.0 effective megapixel APS-C crop CMOS digital single-lens reflex camera made by Canon. It was announced on September 1, 2009...
, 60DCanon EOS 60DThe Canon EOS 60D is a digital single-lens reflex camera from Canon. It is part of the Canon EOS line of cameras and succeeds the EOS 50D. It was publicly announced on August 26, 2010....
, 1D Mark IV - FujifilmFujifilmis a multinational photography and imaging company headquartered in Tokyo, Japan.Fujifilm's principal activities are the development, production, sale and servicing of color photographic film, digital cameras, photofinishing equipment, color paper, photofinishing chemicals, medical imaging...
: FinePix S3 ProFinePix S3 ProThe Fujifilm FinePix S3 Pro is an interchangeable lens digital single-lens reflex camera introduced in February 2004. Its successor, the Finepix S5 Pro, was released on 25 September 2006...
, FinePix S5 ProFinepix S5 ProThe FinePix S5 Pro is a digital single lens reflex camera introduced by Fujifilm on25 September 2006 and since discontinued. It replaces the previous FinePix S3 Pro and keeps the Nikon F mount compatibility, including DX size lenses. It is based on the Nikon D200 body, and benefits from its...
, FinePix IS ProFinePix IS ProThe FinePix IS Pro is a digital single lens reflex camera introduced by Fujifilm in 2007. It is based on a FinePix S5 Pro, which is in turn based on the Nikon D200. It has a Nikon F lens mount and can use most lenses made for 35 mm Nikon SLR cameras. It replaces the Fujifilm FinePix S3 Pro... - Leica: Digilux 3Leica Digilux 3The Digilux 3 is a digital single-lens reflex camera introduced by Leica on 14 September 2006. The Digilux 3 and the Panasonic Lumix DMC-L1 are identical cameras, using the Four Thirds standard lens mount and featuring a 7.5 Megapixels live view N-MOS sensor, but the Digilux 3 has improved firmware...
- NikonNikon, also known as just Nikon, is a multinational corporation headquartered in Tokyo, Japan, specializing in optics and imaging. Its products include cameras, binoculars, microscopes, measurement instruments, and the steppers used in the photolithography steps of semiconductor fabrication, of which...
: D90Nikon D90The Nikon D90 is a 12.3 megapixel digital single-lens reflex camera model announced by Nikon on August 27, 2008. It is a prosumer model that replaces the Nikon D80, fitting between the company's entry-level and professional DSLR models. Nikon gives the D90's Estimated Selling Price in the U.S...
, D300Nikon D300The Nikon D300 is a 12.3-megapixel professional DX format digital single-lens reflex camera that Nikon Corporation announced on 23 August 2007 along with the Nikon D3 FX format camera. It replaced the D200 as Nikon's DX format flagship DSLR...
, D300sNikon D300SThe Nikon D300S is a 12.3 megapixel DX format digital single-lens reflex camera announced by Nikon on 30 July 2009. It replaces the D300 as Nikon's DX format flagship DSLR adding HD video recording...
, D700Nikon D700The Nikon D700 is a professional grade full-frame digital single-lens reflex camera introduced by the Nikon Corporation in July 2008 and manufactured in Japan. It uses the same 12.1 megapixel "FX" CMOS image sensor as the Nikon D3, and is Nikon's second full-frame digital SLR camera...
, D5000Nikon D5000The D5000 is a 12.3 megapixel DX format DSLR Nikon F-mount camera, announced by Nikon on 14 April 2009, and rumored to have been discontinued in November 2010. Although it is listed as discontinued on the Nikon Japan website, it is still available in other regions as of April 2011. The D5000 has...
, D5100Nikon D5100The Nikon D5100 is a 16.2 megapixel DX format DSLR F-mount camera announced by Nikon on April 5, 2011. It features the same 16.2-megapixel CMOS sensor as the D7000 with 14-bit resolution, while delivering Full HD 1080p video mode with up to 30fps...
, D3100Nikon D3100The Nikon D3100 is a 14.2 megapixel DX format DSLR Nikon F-mount camera announced by Nikon on August 19, 2010. It replaces the D3000 as Nikon's entry level DSLR. It introduces Nikon's new EXPEED 2 image processor and is the first Nikon DSLR featuring full high definition video recording with full...
, D3Nikon D3The Nikon D3 is a 12.1 megapixel professional grade full frame digital single lens reflex camera announced by the Nikon Corporation on 23 August 2007 along with the Nikon D300 DX format camera. The D3, along with the Nikon D3X, was a flagship model in Nikon's line of DSLRs, superseding the D2Hs...
, D3xNikon D3XThe Nikon D3X is a 24.5 megapixel professional-grade full frame digital single-lens reflex camera announced by the Nikon Corporation on 1 December 2008. The D3X is the third camera in Nikon's line to offer a full frame sensor, following the D3 and D700...
, D7000Nikon D7000The Nikon D7000 is a 16.2 megapixel digital single-lens reflex camera model announced by Nikon on September 15, 2010. It is a new class of camera placed between the professional D300S and the 'midrange' D90... - OlympusOlympus Corporationis a Japan-based manufacturer of optics and reprography products. Olympus was established on 12 October 1919, initially specializing in microscope and thermometer businesses. Its global headquarters are in Shinjuku, Tokyo, Japan, while its USA operations are based in Center Valley, Pennsylvania,...
: E-10Olympus E-10The Olympus E-10 is a digital single-lens reflex with a 4.0 megapixel CCD image sensor that was introduced in 2000. Unlike most digital SLRs the camera is not a system camera – its lens is fixed to the body. It has a TTL optical viewfinder, and a 4× optical zoom lens with lens aperture f/2–2.4...
, E-20Olympus E-20The Olympus E-20 is a 5-megapixel non-interchangeable lens DSLR manufactured by Olympus of Japan, as a successor to its E-10 model....
, E-330Olympus E-330The Olympus E-330 is a DSLR launched on 30 January 2006, using the Four Thirds System lens mount standard. Its main feature is its live image preview functionality, permitting an image to be previewed on the LCD screen. While live image preview is not new in compact digital cameras, the E-330 is...
, E-410Olympus E-410The Olympus E-410 is a 10 megapixel digital single-lens reflex camera intended be the smallest and lightest DSLR on the market...
, E-420Olympus E-420The Olympus E-420 is a 10 megapixel digital single-lens reflex camera made by Olympus. The camera conforms to the Four Thirds System standard, and together with its siblings in the E-4XX series it is marketed as the smallest DSLR in the world.-Features:As with the E-400 and E-410 before it, the...
, E-450Olympus E-450The Olympus E-450 is a 10 megapixel digital single-lens reflex camera made by Olympus and conforming to the Four Thirds System standard. E-450 was announced in March 2009, and shipping started in May the same year...
, E-510Olympus E-510The Olympus E-510 is a 10 megapixel digital single-lens reflex camera oriented to the "prosumer" or "hobbyist" market. Announced in March 2007 to succeed the E-500, it represents the first use of the new Panasonic MOS sensors instead of the Kodak CCD sensors that Olympus had used previously...
, E-520Olympus E-520The Olympus E-520 is a 10 megapixel digital single-lens reflex camera. Announced in May 2008 to succeed the E-510, it adds face detection technology, auto focus Live preview, wireless flash capability and shadow adjustment technology...
, E-620Olympus E-620The Olympus E-620 is a Four Thirds digital single-lens reflex camera from Olympus announced February 24, 2009. It combines features of the E-420 , E-520 , and E-30 .-Features:The camera is marketed by Olympus as the world's smallest DSLR with built-in image stabilization...
, E-30Olympus E-30The Olympus E-30 is a Four Thirds System camera, sitting between the Olympus E-520 and the E-3 cameras in terms of size, weight, capabilities and price. It is sold in a kit with the Zuiko Digital ED 14–54mm f2.8–3.5 II lens....
, E-3Olympus E-3The Olympus E-3 was until 2011 Olympus Corporation's previous flagship camera, positioned as a professional DSLR camera. It is the successor to the Olympus E-1, which was launched in November 2003. The E-3, originally codenamed Olympus E-P1, was announced on 17 October 2007. The E-3, like the other...
, E-5Olympus E-5The Olympus E-5 is Olympus Corporation's flagship camera, positioned as a professional DSLR camera. It is the successor to the Olympus E-3, which was launched on October 17, 2007. The E-5 was announced on September 14, 2010... - PanasonicPanasonicPanasonic is an international brand name for Japanese electric products manufacturer Panasonic Corporation, which was formerly known as Matsushita Electric Industrial Co., Ltd...
: DMC-L1Panasonic Lumix DMC-L1The Lumix DMC-L1 was Panasonic's first digital single-lens reflex camera, and was announced in February 2006. This camera adheres to the Four Thirds System lens mount standard, making it the first non-Olympus Four Thirds camera, and thus confirming that the Four Thirds System is a semi-open...
, DMC-L10Panasonic Lumix DMC-L10The Lumix DMC-L10 is Panasonic's second digital single-lens reflex camera , a follow-up to the previous Lumix DMC-L1 model. It was announced in August 2007, and, like the Lumix DMC-L1, this model uses the Four Thirds System lens mount standard and contains some basic parts provided by Olympus... - Sony: A300, A330, A350, A380, A500, and A550
- PentaxPentaxPentax is a brand name used by Hoya Corporation for its medical-related products & services and Pentax Ricoh Imaging Company for cameras, sport optics , etc. Hoya purchased and merged with the Japanese optics company on March 31, 2008. Hoya's Pentax imaging business was sold to Ricoh Company, Ltd...
: K20DPentax K20DThe Pentax K20D and its clone, the Samsung GX-20, were 14.6 megapixel digital single-lens reflex cameras manufactured by Pentax that were announced on January 23, 2008. The K20D was available in the U.S...
, K-7Pentax K-7The Pentax K-7 is a 14.6-megapixel digital single-lens reflex camera, announced on 20 May 2009. This is the first new flagship model released by Pentax since its merger with Hoya Corporation on 31 March 2008.- Features :...
, K-xPentax K-xThe Pentax K-x is a 12.4 megapixel digital single-lens reflex camera, announced on September 16, 2009. Pentax K-x uses an Exmor, Sony-made sensor . In some cases it even approaches the quality produced by full-frame DSLRs like the Nikon D700 and the Canon 5DMkII, both with larger sensors...
, K-rPentax K-rThe Pentax K-r is a 12.4-megapixel digital single-lens reflex camera, announced on September 9, 2010. The K-r is available in 3 body colors in North America, with other colors available only in the Japanese market. The K-r introduces a new SAFOX IX autofocus system and has a 3-inch...
, K-5Pentax K-5The Pentax K-5 is a 16.3-megapixel digital single-lens reflex camera, announced on 20 September 2010. It began shipping in mid-October 2010.Externally, the camera body is almost unchanged from the Pentax K-7... - SamsungSamsungThe Samsung Group is a South Korean multinational conglomerate corporation headquartered in Samsung Town, Seoul, South Korea...
: GX-20
The principal function of live preview on Canon DSLRs from the 20Da onwards has been allow, via LCD viewing, rapid acquisition of consistent and predictable exposure selection before taking a photograph via its 'exposure simulation' (ExpSim) enabled mode, or exposure priority display. This mode replaces the shortcomings of traditional estimation involved in the through-the-lens (TTL) metering
Through-the-lens metering
Through-the-lens metering is a photographic term describing a feature of cameras capable of measuring light levels in a scene through their taking lenses, as opposed to a separate metering window...
techniques of the older framing type live view DSLRs with autogain/framing only, DSLRs without live view, as well as the shortcomings of optical viewfinders when ambient lighting
Available light
In photography and cinematography, available light or ambient light refers to any source of light that is not explicitly supplied by the photographer for the purpose of taking photos. The term usually refers to sources of light that are already available naturally or artificial light already being...
becomes too low.
Real time exposure simulation live preview (or exposure priority display) had been available in many prosumer cameras, such as the Canon PowerShot G series, before being available to in live view DSLRs. Some manufacturers of compact cameras, including prosumer models, still lack this exposure simulation live view feature, instead relying on the more rudimentary autogain/framing only live view, where slow focus and slow exposure estimation via TTL metering techniques are relied upon. Real time exposure simulation capable live preview digital cameras make achieving the desired exposures, especially in manual modes, more quickly available for both still and video photography.
Among the DSLRs that do manage to focus using the standard phase-detection sensors used by DSLRs, unlike some compact digital cameras none has managed to show 100% frame coverage. This removes one of the key advantages of live preview over optical viewfinders, especially on more budget cameras. Additionally, 100% coverage optical viewfinders have recently become more common and affordable with the appearance of the Canon EOS 7D
Canon EOS 7D
The Canon EOS 7D is an 18.0 effective megapixel APS-C crop CMOS digital single-lens reflex camera made by Canon. It was announced on September 1, 2009...
, Nikon D300, Olympus E-3 and the Pentax K-7.
Some real time exposure simulated capable live preview digital cameras also offer live histogram
Histogram
In statistics, a histogram is a graphical representation showing a visual impression of the distribution of data. It is an estimate of the probability distribution of a continuous variable and was first introduced by Karl Pearson...
graphs for tonal balance
Image histogram
An image histogram is a type of histogram that acts as a graphical representation of the tonal distribution in a digital image. It plots the number of pixels for each tonal value. By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a...
or color
Color histogram
In image processing and photography, a color histogram is a representation of the distribution of colors in an image. For digital images, a color histogram represents the number of pixels that have colors in each of a fixed list of color ranges, that span the image's color space, the set of all...
, where the graph changes instantaneously as exposure adjustments are made.
Other features include live depth of field (DOF)
Depth of field
In optics, particularly as it relates to film and photography, depth of field is the distance between the nearest and farthest objects in a scene that appear acceptably sharp in an image...
preview, and live indication of overexposed
Exposure (photography)
In photography, exposure is the total amount of light allowed to fall on the photographic medium during the process of taking a photograph. Exposure is measured in lux seconds, and can be computed from exposure value and scene luminance over a specified area.In photographic jargon, an exposure...
areas of the image
Almost all modern bridge and compact cameras have a movie mode, while this feature only became available on DSLRs during 2008. The Nikon D90
Nikon D90
The Nikon D90 is a 12.3 megapixel digital single-lens reflex camera model announced by Nikon on August 27, 2008. It is a prosumer model that replaces the Nikon D80, fitting between the company's entry-level and professional DSLR models. Nikon gives the D90's Estimated Selling Price in the U.S...
with 720p
720p
720p is the shorthand name for 1280x720, a category of High-definition television video modes having a resolution of 1080 or 720p and a progressive scan...
video was announced in August 2008, and the Canon EOS 5D Mark II
Canon EOS 5D Mark II
The Canon EOS 5D Mark II is a 21.1-megapixel full-frame CMOS digital single-lens reflex camera made by Canon. It succeeds the EOS 5D and was announced on September 17, 2008.-Improvements compared to original EOS 5D:...
with 1080p
1080p
1080p is the shorthand identification for a set of HDTV high-definition video modes that are characterized by 1080 horizontal lines of resolution and progressive scan, meaning the image is not interlaced as is the case with the 1080i display standard....
video was announced in September 2008. The Canon EOS 5D Mark II
Canon EOS 5D Mark II
The Canon EOS 5D Mark II is a 21.1-megapixel full-frame CMOS digital single-lens reflex camera made by Canon. It succeeds the EOS 5D and was announced on September 17, 2008.-Improvements compared to original EOS 5D:...
was the first DSLR to offer full control over its real time exposure simulation live preview for video, rather than just autogain/framing only live preview.