DSLR Cameras

DSLR cameras represent what are often considered the preeminent digital capture technology available today through their meshing of the highest image quality, speed, intuitiveness, and modular capabilities to suit nearly any type of photography imaginable. Being the first step toward serious photography for many, or simply additional tools or upgrades for the veteran, DSLRs cover a broad expanse of capabilities and are often designed to meet specific goals while still retaining the overall imaging benefits that are suitable to many.


From their beginning, DSLRs were designed to reflect the most popular type of film camera, the SLR. This single lens reflex design traditionally incorporates an optical viewfinder, reflex mirror, and single taking-and-viewing lens to function properly. While digital cameras are not constrained to the same physical limitations as film SLRs were, they still revolve around the basic premise of design that includes a viewfinder, a reflex mirror (with some recent notable exceptions) and an interchangeable-lens system. When searching for a DSLR, there is a range of options to consider regarding what type will best suit one’s own personal needs. Not all photographers need to have the ability to record still photographs at an impressive 36.3MP, nor do all photographers need to rely on compact and lightweight solutions, since the greater emphasis might be tripod-based work or other shooting styles where a larger and faster body is most beneficial.




Lenses

One of the most important characteristics to consider when choosing your ideal DSLR is its compatible system of lenses. Lenses are, somewhat arguably, the most important tools for elevating the actual quality of imagery and can be the deciding factor between professionally rendered photographs and average snapshots. Since the choice of a DSLR directly affects the type of lenses being used, this is the first crucial step. Take into consideration any currently owned lenses and if they are compatible with different DSLRs of interest. Lenses often end up being the constant investment over time in regard to photography equipment, with the camera bodies fluctuating more quickly.

DSLR Types and Sensor Size

Currently, the two main sizes of image sensors in DSLRs—full frame and APS-C—have their own benefits as well as some drawbacks. APS-C-sized sensors, also called DX format or cropped sensors, are the most common sensor size found in most entry level, mid-range, and even some professional-grade DSLRs. This sensor size is slightly smaller than a full-frame sensor, which is based on the traditional 35mm film-frame area: about 36 x 24mm. APS-C sensors 
measure approximately 23.5 x 15.6mm, with some variance, depending on manufacturers. This smaller sensor size gives a narrower apparent field of view when shooting with the same focal-length lens, since the sensor is essentially a predefined crop of the image circle that is represented in 35mm/full-frame terms, hence the term crop sensor. The effective "crop factor" that can be used with APS-C sensors is approximately 1.5x for most brands and 1.6x for Canon, for determining a representative focal-length equivalent for lenses. Since the field of view is narrower with an APS-C sensor than a full-frame sensor, a 50mm focal length on an APS-C camera will provide approximately the same field of view as a 75mm lens. This added sense of reach offered by an APS-C-sized sensor is conducive to shooting wildlife, sports, and in other situations where longer focal lengths are the norm.

A full-frame sensor, on the other hand, offers greater image quality and detail simply due to the larger physical size of the sensor—there is physically more room on the sensor for information. Similar to comparing medium format film with 35mm film, a full-frame sensor compared to an APS-C sensor is typically able to acquire greater tonal fluency and color gradations as well as improved low-light performance—higher ISO ranges and lessened image noise—because the size of the actual pixels is larger, as well. Since there is no crop factor associated with a full-frame camera, too, there is a greater array of prime wide-angle lenses available.

The physical size of the camera is also derivative of the sensor size; APS-C cameras tend to be smaller and lighter weight compared to their full-frame counterparts. When coupled with longer, or more, lenses plus accessories, an APS-C camera is often the ideal companion for traveling or at times when portability is an asset.


Other Form-Factor Considerations

Besides the size of the sensor, other factors determine the overall physical size and weight of a DSLR. Other elements like the viewfinder type, LCD screen size, integrated battery grip, and other features can all affect how large and heavy a camera is (none of which are necessarily contingent on the size of the sensor alone). One of the most considerable factors in weight is the material used to construct the body: typically some kind of a metal chassis, an all-polycarbonate design, or a hybrid of the two. All metal, often magnesium-alloy body designs, such as the Nikon D4, provide the greatest durability and innate weather protection, but at the cost of extra weight.


These metal-body designs also possess more tactility due to their heft; they often have a greater feeling of presence compared to more compact, lighter-weight options. An all-polycarbonate body, like the Canon EOS Rebel SL1, is often reserved for more value-intended bodies or lightweight, entry-level models. The lack of metal in the frame does offer less rigidity than a metal chassis, but does significantly lessen the overall load. Many bodies throughout the true entry-level to true professional range have different ratios of both metal and plastic to straddle the line between durability, weather sealing, and lightweight portability.




Different Grades of DSLRs

Entry-Level

An entry-level DSLR is the most affordable type of DSLR and typically stands to be either a photographer's entry point into interchangeable-lens cameras, or can function equally as well as a backup camera for a working professional, or a traveling camera for an enthusiast. The designation “entry-level” simply refers to a mixture of attributes and features that render the camera especially friendly and functional to use, as a good starting point, and as something to progress from once a greater understanding of camera and exposure controls is understood. The imaging quality of these cameras is by no means diminished, but rather the range of options for how to control the DSLR tends to lean more towards automated options and a variety of preset effects for achieving a certain look without the rigorous know-how needed if you were to use an entirely manual camera.
Entry-level cameras will most often feature an APS-C-sized sensor and polycarbonate construction, to make them compact and lightweight. Since its goal is to serve as an apt bridge from a point-and-shoot or similar camera, it is not alienating in its stature when compared to larger, professional-targeted models. Other nods toward a more compact size include the incorporation of a pentamirror viewfinder, as opposed to a pentaprism, and a smaller array of physical dials and buttons on the top and rear plates of the body. This is still to say, though, that a DSLR’s main asset, aside from improved image quality and speed, is its range of configurability.

This regard is not lost on entry-level bodies, since all still include the ability to adjust exposure settings using program, aperture priority, shutter priority, and manual exposure modes, but complements these conventional modes with the inclusion of intelligent, automated shooting modes, creative-effect modes, scene modes, and panoramic modes. These intuitive auto and creative modes strive to lessen the burden of post-production and increase the efficiency of producing a share-worthy image directly in-camera. Additionally, many entry-level DSLRs also feature guide modes to help familiarize oneself with all of the controls and settings of a DSLR for a greater understanding of exactly how to produce specific types of imagery.

Intermediate

Next in line is the expansive "intermediate" category, which encompasses the greatest number of DSLRs ranging between entry and professional levels. This is one of the most constantly expanding regions of camera technologies and is often the range of cameras in which the forefront of evolution begins, such as in the case of the Canon EOS 70D, which offers redefined autofocus technology along with an enhanced feature set, compared to its predecessor. Intermediate cameras can feature either APS-C or full-frame sensors and typically utilize some blend of both polycarbonate and alloy to produce a body design that is compact, lightweight, and durable. Intermediate DSLRs stand as a common growing point for someone looking to upgrade from their first DSLR and, just like entry-level DSLRs, are valuable backup options for working shooters who need more than one body.
Intermediate DSLRs will often combine both a structure of automatic shooting options and creative modes along with an expanded set of manual controls, allowing the user to shoot in his or her preferred manner or skew the camera’s settings based on specific shooting situations. Faster AF performance, a more accurate exposure-metering system, and a larger buffer along with a quickened continuous shooting rate are also all features that begin to become more prominent when upgrading to the intermediate line of DSLRs. Each of these technical improvements leads to greater honing of one’s own personal visions, whether it be sports and nature shooting or portraiture and still life; intermediate DSLRs become the beginning point where photographers can pair a camera more to their own personal traits, and often each brand will offer several veritable options that all meet individual criteria.

Video recording is also upgraded in this realm of cameras, with most of them supporting full HD 1080i or 1080p recording with the ability to manually control exposure and audio settings while recording. They commonly feature connectivity for an external microphone to enhance audio for video and also have hot shoes for adding lights, flashes, or other mounted accessories.


Professional

Professional-grade DSLRs are typically the flagship camera of a company and are known to represent the highest quality in regard to physical build, manual control, image quality, sensitivity, and speed. Typically featuring full-frame-sized image sensors and top-of-the-line image processors, professional DSLRs separate themselves most simply in regard to attaining the most detail and clarity when shooting both still photographs and video. However, a number of APS-C cameras can still be considered professional grade, such as the Nikon D300s, which employs a fast continuous-shooting rate along with an advanced autofocus system that benefits from the crop sensor format to render it as a prized camera for sports and wildlife photography.
When moving up to a professional DSLR, photographers are typically familiar with exactly what they need from a camera and understand the controls they need in order to accomplish a specific intention. Full manual control to the utmost regard is a standard feature in professional DSLRs, with the ability to fine-tune focus-point selections, exposure compensation and bracketing settings, and manage a range of video frame rates and continuous-shooting speeds. Also common in professional DSLRs is the inclusion of dual memory card slots, either for greater storage capacity or in-camera duplication and backing up of files, as well as a greater variety of interfacing abilities and connection ports like flash-sync ports, external RAW video recording, and both a microphone and headphone jack for enhanced audio recording with videos. More physical controls and dials are also availed in order to increase efficiency and controllability while shooting.

Professional DSLRs tend to be split into two main categories, the speed and low-light category and the high-resolution category. These two categories fit the working photojournalist, sports, or reportage shooter, or the art, commercial, or portraiture shooter, respectively. At this level, the ability to pair a camera to one’s own shooting needs is more important than having an all-around solution that cannot perform at the highest level in one’s chosen area. For some, the benefits of having a full-resolution 18MP continuous shooting rate of 12 fps far outweigh the ability to produce 16 x 24” prints at 300dpi directly from the camera.


Main Technologies to Consider

Sensor and Image Processor

The image sensor and processor are the central, core elements of a DSLR and are responsible for the imaging capabilities they possess. As previously mentioned, the two common sensor sizes are APS-C and full frame, each of which has its own inherent benefits in respect to imaging quality and the field of view with paired lenses. When combined with an imaging processor, the two technologies work together to enable video recording, continuous shooting, and the range of ISO sensitivities and image quality in difficult lighting conditions. Some cameras, such as the Canon EOS 7D, utilize multiple image processors to aid in even faster performance, making them ideal for high-speed continuous shooting and video recording. While a processor facilitates faster continuous-shooting rates, it also helps to process higher resolution and RAW file types more effectively.


Autofocus

The autofocus system is another highly important feature of DSLRs to which most users should pay much attention. Autofocus systems are evolving constantly, with newer systems utilizing two different focusing methods in order to provide sharp focus that is both precise and fast. Conventionally, DSLRs use a phase-detection method for acquiring focus that employs a number of fixed AF points in order to acquire focus based on detected objects throughout the scene. The greater the number of AF points, the more precision with which the AF system can function in a timely manner, since the points will be covering a larger, and more dense area of the scene. Beyond the actual number of focus points there are also different types of points, such as cross-type points and points that are sensitive at certain apertures.Cross-type points are, as their name implies, a type of focusing point, or sensor, that is a physical cross (+) versus a standard point that is only a vertical line (|). When these standard sensors work to determine focus, they split incoming light in one dimension; cross-type sensors split incoming light in two dimensions to acquire focus more easily in a greater range of lighting scenarios. Furthermore, many cameras feature specific points, most commonly the center point, that are capable of focusing with lenses with a maximum aperture of f/5.6 or f/8. Seemingly, this doesn’t appear to be a big deal since even the slowest lenses have a maximum aperture of at least f/5.6. However, when working with longer telephotos attached to a 1.4x teleconverter, that maximum aperture is subsequently halved, making it effectively f/8. On cameras that only have a focusing point sensitive to f/5.6, these teleconverter-enabled lenses will not be able to reap the autofocusing benefits of the camera, since there is not enough light being delivered to the sensor during composition.


The second focusing method that is currently being integrated into some DSLRs is contrast-detection focusing, which up until recently has been relegated only to cameras without a mirror, such as point-and-shoots and mirrorless cameras. This type of focusing is sensor based, and thus cannot function with the reflex mirror down, since it is directing all of the light through the optical viewfinder. Contrast-detection focusing works when shooting movies or still images in live view and, in certain Sony cameras, like the Alpha SLT-A99, works all of the time due to their use of Translucent Mirror Technology. Since the A99 and other similiar cameras have a translucent mirror design, they also consequently utilize an electronic viewfinder, rather than an optical viewfinder. As previously mentioned, too, the Canon EOS 70D also employs contrast-detection focusing in a unique way via Canon’s Dual Pixel CMOS AF, which allows for highly controllable, touch-enabled live view focusing, due to its incorporation of two separate photodiodes within each pixel for an even denser network of phase-detection-gathering elements.




Image Stabilization

One of the most useful assets for many photographers is some form of image stabilization, which helps to minimize the appearance of camera shake caused by lengthy shutter speeds or longer focal lengths. There are two main types of image stabilization available: lens-shift type image stabilization and sensor-shift type image stabilization. Depending on manufacturer, some prefer to incorporate the necessary stabilization systems within the lenses whereas other manufacturers prefer to incorporate in-camera image stabilization.
The benefit of having in-camera image stabilization is that any mounted lens effectively becomes stabilized and reaps the benefits of the system for more effective hand-held shooting capabilities. On the other hand, the benefit of incorporating image stabilization within select lens designs is that it can be tailored specifically for a certain lens in order to maximize stabilization performance, and is subsequently more effective than body-based stabilization.






Monitors and Viewfinders

All current DSLRs provide both a rear monitor, for live view monitoring, image playback, and menu navigation, and a viewfinder for eye-level finding when composing imagery. With the exception of the Sony Translucent Mirror cameras, DSLRs utilize an optical viewfinder system with either a pentaprism or pentamirror design. Pentaprisms are the more traditional means for designing a viewfinder for single-lens reflex cameras and are constructed from glass to provide a bright image when viewing. This comes at the expense of slightly greater weight and size when compared to the pentamirror, which employs a system of mirrors to produce a viewable image, albeit slightly darker than that of a pentaprism. High-end cameras tend to have pentaprisms, whereas entry-level DSLRs more often use pentamirrors in order to maintain the camera’s light weight and compact appeal. One other consideration to note when comparing viewfinders is their frame coverage, which is usually within a range of 95 to 100%. 100% is the ideal choice in order to see everything within the frame during compositions, but some cameras lose a small portion of the image due to design constraints, and therefore have less than 100% frame coverage.


Rear monitors are an area of the digital camera that has seen significantly more improvements over the years than viewfinders, and are beginning to grow in size, increase in resolution, and integrate articulating capabilities to better support viewing from high and low angles. Most cameras have either a 3.0-inch or, more recently, a 3.2-inch monitor with resolutions ranging from 230k-dot to well over one million pixels. The higher the resolution, the sharper and brighter the image will be on the monitor. Many monitors also benefit from a tilting or a swiveling design that will allow the screen to be positioned in such a way that it can be used from high or low angles without your having to crawl on the ground or simply point and shoot from higher angles.Lastly, many screens now also feature a touchscreen design, which allows for both menu navigation as well as direct camera and focus controls from the screen itself. Particularly helpful for focusing and metering, with a touch-enabled system, one can pinpoint specific areas for critical focus and spot exposure metering for greater control than an average metering or focusing system. Touchscreens are also generally more intuitive to work with compared to using separate wheels, dials, or directional pads for navigating through menus and viewing photos or movies.





Video Recording

With Nikon’s announcement of the D90 in 2008, high-definition video recording has been an integral feature of DSLRs and since then has expanded into one of the most important and noteworthy technologies for a camera. DSLRs and their use in the professional and enthusiast video realms has grown incredibly quickly due to a number of benefits that DSLRs offer when compared to video cameras, including the physical size of the image sensor and the ability to utilize a much larger array of lenses.
Since the introduction of video and its increased popularity, the video quality and capabilities of a DSLR in regard to producing high-quality movies has also grown substantially. Most DSLRs, from entry level to professional, are capable of recording full HD 1920 x 1080 video for vivid playback and rich editing capabilities and, additionally, the incorporation of an HDMI output on many cameras allows direct linking of the camera to an HDTV for full-quality playback. As the look of video has been refined, the audio-recording capabilities have also been enhanced; first, through the incorporation of an external microphone jack and second, with the inclusion of a headphone jack. If recording video with a DSLR is a main focal point of its use, both of these are a definite necessity. Aside from the higher recording fidelity of an external microphone, its main benefit is the actual placement of it away from the camera in order to minimize the possibility of recording zooming, focusing, or other internal noise.
The other main aspect of which to make note when comparing different DSLRs' video abilities is the range of controls available for exposure control and audio control. It is crucial for a camera to posses a full range of exposure adjustments in order to be used for serious video applications, including aperture, shutter speed, and ISO sensitivity controls as well as audio-level manipulation and multiple, selectable frame rates. With a greater range of controls available, more filmic effects can be achieved and as such, the camera can be effectively used along with numerous HDSLR and support accessories for garnering the highest quality motion pictures possible.






Accessory Support

One of the final points to take into consideration when comparing DSLRs should be the range of supported accessories available to ensure seamless use of flashes, remotes, and more. Many DSLRs feature a built-in pop-up flash in addition to the hot shoe; the hot shoe provides the obvious support for an external flash. However, some cameras' built-in flash can actually serve as a commander for off-camera flashes to extend its capabilities well beyond that of a stereotypical on-camera flash. Numerous entry-level, intermediate, and some professional cameras also accept optional battery grips in order to provide a more comfortable hold on the camera body, additional access to controls when shooting in the vertical orientation, and extended battery life.


How to Select a DSLR

When choosing a DSLR, a large number of evaluations need to be considered in order to pair an appropriate camera to one’s skill, needs, and applicable subjects. Beginning with experience, form factor, and use, smaller, entry-level cameras are often the most practical choice as a first step into the world of DSLRs and are incredibly versatile due to their small form and value. Even though these models employ the greatest number of automated controls, they can still be used manually as an adept backup camera for the working professional. Professional-level cameras typically revolve around the highest performance, but can often lack many of the shooting modes, controls, and general support many photographers require for their needs. Unless familiar and confident with working manually, entry-level and intermediate cameras are often the most intuitive and friendly cameras for many photographers, and allow one’s ability to progress along with his or her familiarity.A DSLR should be evaluated based on some its most general and comparable specifications, including resolution, monitor size, maximum ISO sensitivity, continuous shooting speed, and movie settings. Evaluation of each of these points and the creation of a hierarchy can lead to fitting a specific body to one’s own needs. When the essential specifications have been narrowed, comparison of some of the extra features or technologies can also then be taken into consideration, such as if a camera features built-in Wi-Fi connectivity or if it supports wireless connectivity through the use of an optional accessory; if it has a range of creative scene modes that sound appealing or if a more streamlined interface is preferred; and last, but not least, the physical form of the camera: how it feels to hold, if a battery grip will become a necessary accessory, and if it is portable enough to suit one’s traveling needs. With the expansive and impressive lineup of currently available DSLRs, there is certain to be an ideal camera for all photographers, and the seeking of that specific one will aid in discovering more about one’s personal preferences and how to approach selecting the proper tools to benefit the overall image making process.

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