Digital SLR camera stands for “digital single-lens reflex camera”. They are considered top of the line professional cameras with interchangeable lens mounts, unlike more affordable camera models with static unchangeable lenses.
These DSLR cameras are known for their excellent image quality and for being closer in design to an older “film style” camera, making these cameras appealing to photographers who have learned on those older camera models. The transition to digital seems to be easier that way, and not only that but the weight and feel of the camera is similar, not to mention the picture quality is excellent, which is most important.
A digital single-lens reflex camera or DSLR camera uses a mechanical mirror systems and what’s called a pentaprism to direct light from the lens all the way to an optical viewfinder at the back of the camera. The light bounces around five times, hence the name pentaprism, coming from the Latin meaning five mirrors, or something close to that translation. The mirrors actually reflect light directly upwards at a 90 degree angle and then four more times by various mirrors to the roof of the pentaprism within the camera body.
A digital SLR camera has a super-fast acting mirror and shutter system so as to not miss any frame of a fast action photo. This is a real deal professional set up which has the ability to break down and capture images to the millisecond, depending on the quality of the set up a digital SLR camera can take roughly three to ten different images within one second. Of course, this camera set up is preferred by still photographers and action photographers alike, because of its versatility, ease of use, and the image quality is well-known throughout the industry.
On a digital SLR camera there will be a variety of interchangeable lenses that a photographer can use, most of the time these lens mounts will be made by the same manufacturer as the individual camera manufacturer to order to ensure compatibility perfection by some brands may be compatible with each other. A professional photographer realizes the increased versatility that is given by using different lens mounts depending on the light quality and the depth of field is extremely important.
Digital SLR cameras allow the photographer to preview the depth of field in order to set up a much better shot. There is often a low signal to noise ratio in the better DSLR cameras, along with larger sensors, so that the film format is closer to an original 35mm format; only the very best digital SLR cameras however will have these large sensors and full frame (35mm like) capability, and these cameras do tend to be very expensive.
Older DLSR cameras did not have a live preview feature, however beginning with the Olympus digital SLR camera model in 2008, now most of these cameras do have this important feature. Also, there is now a high definition or HDSLR camera with an HD movie-mode feature.
The Nikon D90 was the first to offer this feature, but this has also proliferated to other brands and models very quickly after it was introduced. The Nikon D90 has a 720p resolution which means it can produce high quality images in resolution of 1280 x 720 pixels, at a rate of 24 frames per second. Not bad, not bad at all, although there are most advanced models.
The first Blu-ray/DCI compliant high definition digital SLR camera is come out was the Pentax K-7 HDSLR model, in the year 2009. It’s resolution was 720 pixels, and it captures images at a very fast rate of 30 frames per second.
In order to appeal to a broader market and to keep costs lower almost all the major camera brands (Nikon, Canon, Sony, and others) have swapped out the high cost pentaprism with what’s called a penta-mirror, which is made from plastic and is much cheaper, but only on certain models. Also, on certain models, they have shrunk down the sensor size in order to keep costs down, this lessens the fullness of the frame, however the costs come down considerably.
The Cannon 1-DS Mark III, a popular digital SLR camera, for example has smaller sensors which can capture about 61% of a full frame camera. Other models have seven smaller sensors and can capture even less of a frame.
Digital SLR cameras are always evolving, they get newer and better features, and the number of models and differences within the models expand and so on and so forth. This, of course, appeals to the consumer who now gets a wide variety of options to choose from.