DSLR Photography – Basics You Should Learn
The most preferred equipment of professional photographers is a Digital SLR (DSLR) camera. DSLR cameras have also been preferred camera of amateur photographers too. But if someone wants to take up DSLR photography newly, s/he will have to learn a bit about these wonderful cameras, their working and the reason for their popularity. Here is some information, you might find useful if you want to become a professional photographer.
Single Lens Reflex
Today the title of single lens reflex (SLR) camera may seem a bit weird, but once upon a time, popularity of TLR (twin lens reflex) cameras was kissing skies and still today there are 1-2 models on sale.
The twin lenses of a TLR have similar focal length and their mechanisms of focusing are linked, but they have different purposes.
The “viewing lens” is meant for focusing when the photographer looks through the waist-level viewfinder, whereas the “taking lens” is perched in front of the film, prepared for exposure in a different chamber.
Do you know how the term “reflex” came? Both TLR and SLR cameras are equipped with a reflex mirror, typically a 45-degree mirror that reflects light coming from the lens in the viewfinder and this is where the term “reflex” comes from.
The mirror is fixed in a TLR and scene can be seen in the viewfinder all through the exposure, while the mirror flips up in a DSLR during exposure to let the light reach the sensor or film; this blanks the viewfinder during the exposure.
In DSLR cameras, there is an optical viewfinder that gets light from the same lens as the one used to capture the photo.
The light that exits the lens is reflected in a pentaprism (pentamirror) while the mirror is down and the pentaprism reflects the light around to create an image on the viewfinder screen which is the right way round.
This helps SLRs to become smaller than TLRs and solve the issue of parallax error faced with rangefinder cameras – the scene is not seen by them through the lens.
Modern viewfinders of DSLR are usually bright and delightful to use, but they cannot display the power of camera settings, unlike the electronic viewfinders occurring in several compact system cameras.
The reflex mirror raises just before an exposure to let light reach the sensor which makes the viewfinder go black at the time of exposure.
When viewfinder composes images, a dedicated AF (autofocus) sensor is used to focus the lens. Phase detection is the feature of this system which can be very fast and works between exposures while the mirror is in the down status.
When the camera is changed to Live View mode and there is the formation of image on the screen on camera’s back, the reflex mirror is elevated and the AF sensor doesn’t get light.
Most DSLR cameras make use of a contrast detection AF technique instead, that utilizes information from the imaging sensor.
It’s a plus point of DSLR cameras over a compact camera is that lens can be changed. However the lens mount is unique to the manufacturer and so, you can use only compatible lenses. Most of the times, compatible lenses are available at third party manufacturers, but it becomes essential to ensure that you have got the correct version, i.e. you should find the best lens for Canon 70D, for example, to achieve your desired quality.
Another point to remember is Canon and Nikon make DSLR cameras with two sensors of different sizes and so, it’s important to ensure that the lens you choose is designed for your camera’s sensor.
These basics should help you in the start of DSLR photography. Keep getting information and make use of it to make the most of your DSLR camera.