To date, before buying optics, many are interested in the question of how to check the lens when buying. Really, we need to take this process seriously. For every system and brand of the camera there are dozens of different variants of lenses on the market, ranging from a modest $ 50 to $ 10,000 (for example: Canon's telephoto lens). Clarifying your needs is the first step to buying lenses. You need to clearly decide what you will shoot. Ask yourself questions like the following ... - Should I shoot indoors or outdoors? - Should I take photos of fast moving objects (for example, sports)? - Do I want to take portraits or make a wedding? - Do I like to shoot wild animals and nature? - Take pictures of landscapes, interiors or architecture? These are the questions that you must ask yourself, and decide on your own budget. If you plan to purchase a digital SLR (DSLR), then, as part of the kit, you will already have a basic lens that makes pretty good photos. However, the main attraction of this type of camera is the ability to switch lenses to get the best frame in any situation. The important question: how to find the right choice for your needs?
Understanding Glass
Before you check the lens when buying, you need to understand what one lens does and how it differs from another, in the first place you need to be familiar with several basic concepts. The focal length, technically speaking, is the focal length of the lens, represented in millimeters, which is the distance between the rear lens of the lens to the focal plane, where the parallel rays of light falling on the lenses converge to a point. This is important to you, because the focal length determines the angle of view of the lens. The smaller the focal length, the wider the field of view of the camera. As the focal length increases, the field of view narrows, so you get a smaller view of objects that looks larger in relation to the environment. In the world of traditional 35 mm film, focal lengths from 16 mm to 35 mm are generally considered wide-angle. A 50mm lens is called "normal", so these lenses are very close to the perception of the human eye, and anything above 100mm is considered a tele photo. However, the focal length is a bit complicated when it comes to DSLRs. This is because the sensors of the image cameras are smaller than 35 mm film, so they cut off part of the image and give the effect of a larger focal length. To get an idea of how this discrepancy will affect the viewing angle of the lens, you need to multiply the crop of the digital camera. The Nikon D40, for example, has a crop factor of 1.5 x. As a result, the 35mm lens has a field of view equivalent to 52 mm when placed on the D40.
Diaphragm
Another key component of how to check the lens when buying is the aperture. This hole is one of the mechanisms that controls the amount of light that passes through the lens of the image sensor. The aperture is usually called in terms of F-stops, and represents a series, such as f / 2.8. The smaller the number, the larger the hole, and the more light enters the camera. The lens of the camera, which opens with a wide aperture, allows you to maintain a higher shutter speed in low light conditions. This can be significant for getting a sharp image from a hand-held camera. Wider openings also provide greater creative freedom, giving you the ability to throw the background out of focus. Before you check the lens when buying, consult well with understanding people, as store employees are not always competent in these matters. Thus you can save your time and money.