How to choose the digital camera. Elements for beginners of
to sell these or those goods, it is necessary to know some of its properties. Selling goods, you can any its property always show BENEFIT for the buyer. Properties of the digital camera are its functionality, characteristics and technologies.
is understood As functionality the fact that this chamber is able, namely: to photograph, shoot video, to write down a sound (dictophone), to reproduce melody MP3 (MP3 a player), eventually to be the store of various information as each chamber has on the board an external data carrier - a memory card on which it is possible to write down any information (in a digital form). *
* - not all chambers have the listed above functionality
characteristics are understood as the following: permission of a matrix, frequency rate of a zoom of a lens, range of focal lengths, svetosil of a lens, the physical size of a matrix, the power supply, the size and display resolution, the modes and radius of action of flash, data carrier type, permission of video, dimensions etc. of
Practically each model of the digital camera has technologies which help with process of photographing (video filming) and improves the final image which the chamber gives. Let`s list some of them: stabilization of the image (optical, due to shift of a matrix, electronic) which practically all chambers are equipped recently. Suppression of effect of “red eyes“ in the program way in the chamber, various effects (sepia, it is black - white, live colors etc.), eventually - subject programs (a portrait, a landscape, night shooting etc.) .
Knowing these properties in some measure, with confidence I can tell that it will be easier for you to sell the digital camera.
So, we will consider the main players in the market of digital cameras - it is Canon, Nikon, Olympus, Sony, Pentax, Panasonic, Samsung, Kodak. The logical question and who is better arises? Actually everything is simple, practically on each category of digital cameras producers turn out the products. To offer the buyer a certain chamber, it is necessary to find out what he expects from it. In other words to reveal requirement.
Need for a certain choice of a chamber, as well as other types of goods, we reveal by means of questions. Let`s give several examples:
1. Chamber sizes, design, color?
2. What camera used earlier? Will help to determine the level of the buyer, it needs only “automatic machine“ or the camera with manual settings.
3. Additional functions: MP3 player, dictophone, games? To ask this question provided that you on a show-window have at least one chamber which supports one of functions.
4. For whom you buy a chamber? Etc. we Will take
, for example the budgetary category, it differs from dearer fellows in material of the case (plasticity), dimensions, naturally, cheaper lenses and the sizes of matrixes, processor power, lack of additional functional and technical characteristics etc. in production. Notice, I did not mention quality of the received photo. And so, when you sell to the buyer this chamber, be sure that quality of those photos will satisfy them as for it a priority is actually not ideal quality, but memory which they receive, using this chamber.
Is natural, is not unimportant to consider at the same time that the buyer can be the adherent of a certain brand, such as Canon, Nikon, Olympus, pointing to what they proved with 20 - ykh years of the last century, working in the direction of the photo. Buying a chamber of these brands, I can be confident that they yield good result regardless of category. It is possible to add also that the buyer of this chamber will not print posters of the big sizes but only or to keep cards 10õ15 on the hard drive of the computer. For persuasiveness of the buyer I can advise to make to you at a stage of the presentation a trial picture and to show it on the chamber screen, at the same time to use digital increase for demonstration of specification, sharpness, clearness, specifying all these advantages.
Other categories which are offered by producers of digital cameras:
- stylish or image chambers (ultrathin, original design);
- chambers for creative shooting (have manual settings);
- chambers with dlinnofokusny lenses (means chambers with big frequency rate of a zoom of a lens);
- semi-professional chambers with not replaceable optics;
- reflex cameras.
Very often it is necessary to compare a film and “figure“. Here some advantages of “figure“ in comparison with a film:
1) the Photosensitive matrix (sensor) instead of a film. Advantage is in what every time when you finish a film, you buy new, and with a matrix you work throughout all life of a chamber (benefit for the buyer - economy at expendables). Addition. Sensitivity. Many amateur photographers, before doing pictures always reflect and in what conditions of illumination they should do pictures, at the same time pay attention to sensitivity of a film of ISO. Therefore when the film loaded in the camera, intended for good conditions of illumination does not come to an end, and the photoshoot did not end and you want to shoot in the evening - or insert a new film with an index “T“, or you are reconciled with inevitably dark photos. The matrix can quickly be adjusted on change of structure of a light stream, providing a natural svetoperedacha in the most different conditions.
2) the Display on which the shot to, and after shooting is visible. For the amateur photographer this, perhaps, main difference from the film camera. An opportunity to see result in the course of photographing, to reject unsuccessful shots, to make a copy - for many the most important and decisive. Some models are equipped with the rotary or rotating displays that considerably increases convenience of work - for example it is possible to crop precisely (to aim) when shooting on outstretched arms in crowd at a concert.
3) Memory cards instead of a film. Yes, again instead of a film. Digital memory on removable carriers. Advantage is that you can use a film once, and a memory card it is possible to use unlimited number of times until it has its vital resource or it does not fail in the mechanical way. Besides, the number of photos which remains on a memory card many times over exceeds quantity of frames on a film.
4) Lens. In general all also as well as in the film camera, but as the size of a matrix is significantly less than a standard shot of a film, the focal length of a lens is proportional 4 - 7 times less depending on the matrix size. Respectively there is an opportunity to do qualitative compact lenses with repeated increase. Many producers actively use this opportunity, letting out TsFK of middle class with the lenses having 6 - 10- and even 12 - a multiple zoom. It not only impresses, but also fine expands possibilities of the amateur photographer.
5) Possibility of simple realization of additional functions. For example, record of video with a sound, work in the mode of a dictophone, MP3 a
6 player) “Figure“ not only is economical, but also is unsurpassed is expeditious. The reporter receives result of shooting at once and quickly sends it to edition by means of Internet. A possibility of the printing of photos by means of the printer at once after shooting without use of the computer, thanks to the standard of the direct press PictBridge.
Important plus became a possibility of the printing of digital photos in specialized minilabs on classical photographic paper. A conclusion of digital files is slightly more expensive than the press from a film, but it is rather caused by novelty and an incomplete demand of similar services. With increase in demand and the competition in the market of the digital press of the price will surely fall.
Principle of work, design of the digital camera.
everything do Modern cameras - to receive a picture, it is enough to user to press the button only. But, all the same interestingly, on what magic the picture gets to a chamber? We will try to explain the basic principles of operation of digital cameras.
Main parts. Generally the device of the digital camera repeats a design of analog. Their main distinction - in a photosensitive element on which the image is formed: in analog cameras it is a film, digital - a matrix. Light through a lens gets on a matrix where the picture which then registers in memory is formed. Now we will investigate these processes in more detail. The chamber consists of two main parts - the case and a lens. In the case there are a matrix, a lock (mechanical or electronic, and sometimes both that and another at once), the processor and governing bodies. The lens, removable or built-in, represents group of the lenses placed in the plastic or metal case. At once for yourself note that the removable lens is present only at reflex cameras.
we will investigate these processes in more detail. The chamber consists of two main parts - the case and a lens. In the case there are a matrix, a lock (mechanical or electronic, and sometimes both that and another at once), the processor and governing bodies. The lens, removable or built-in, represents group of the lenses placed in the plastic or metal case. At once for yourself note that the removable lens is present only at reflex cameras.
Fig. The reflex camera without lens.
Where turns out the picture. A matrix - film substitute in digital cameras and camcorders (video cameras). A semiconductor photosensitive element which transfers the image created by a chamber lens to an electric signal. The matrix consists of a set of photosensitive cells - pixels which certain number forms concept permission. Also it is worth knowing that increase of megapixels of a matrix does not improve quality of pictures in itself, and matters only at increase in the size of the print (photo). And that, only in case of compliance of resolution of a matrix (in megapixels) to the physical size of a matrix (in inches on diagonal) which almost is never specified in price tags, and also the svetosil and resolution of optics. Otherwise, increase in number of megapixels makes only marketing sense. And, in any case, it is necessary to know that with other things being equal, from two matrixes having the identical geometrical sizes, the matrix having the bigger number of megapixels will give more noisy pictures (Canon A630/640: 8 and 10 megapixels respectively).
the greatest popularity was received Today by a matrix like CCD (a CCD - the device with charging communication) which is used in compact and the majority reflex cameras. The type of a matrix of CMOS (KMOP) is less popular, is used only in the zekalny Canon cameras, and the semi-professional camera with not replaceable Sony R1 optics.
was mentioned Earlier the physical size of a matrix on which quality of a picture which is very often mentioned by buyers directly depends. With increase in the size of a matrix, also quality of a picture potentially improves. If the size of a shot of a film and matrix in digital reflex cameras is measured in millimeters, specifying length and width, for example 23,7õ15,7 mm, 22,5õ15 mm, then in not reflex cameras (soap trays) parameter is measured in inches. The most applied physical sizes of matrixes (in inches) for compact digital cameras in process of their increase in a size are specified below:
1/2,7“ - are applied in chambers of the budgetary category. 1 / 2,5“ - are also applied in some chambers of the budgetary series, but in the majority a case in chambers of stylish category (ultracompact) and in chambers with dlinnofokusny lenses (means with 10 and 12kh a multiple zoom). 1 / 1,8“ and 2/3“ - are used in chambers for a creative skhemka and semi-professional chambers with not replaceable optics with the resolution of matrix not less than 5 - 7 Megapixels.
For comparison, in the majority digital amateur video cameras is used a matrix with a size of 1 / 6“, 1/5“ or 1/4,5“ which it is less even the smallest matrix in a camera 1/2,7“. At the same time here to speak about quality of pictures by itself not to have.
Directly light on a matrix gets through a lens. The lens is an optical system which consists from several lenses and more. The main property of lenses - ability to transfer images of objects. But lenses possess a number of the shortcomings which are not allowing to receive high-quality images. The distortions arising when forming the image are called aberrations. If to collect several lenses with various characteristics are consecutive, the distortions given by them together will be much less, than aberrations of each of them separately. The more lenses - the less aberration and the less light gets on a sensor. Glass whatever transparent it seemed to us does not pass the whole world - some part dissipates, something is reflected. That lenses passed as much as possible light, apply the special clarifying dusting on them. If to look at a chamber lens, it will be visible that the surface of a lens is poured by a rainbow - it is and there is a clarifying dusting.
The focal length is a distance from the optical center of a lens to a matrix (film). It is possible to determine frequency rate of a zoom of a lens by the focal length (FL), namely having divided the FR maximum value into minimum. Frequency rate is equal in our case 3kh as 23,4/7,8=3kh. Easier way of determination of frequency rate of a zoom is the inscription on the chamber case in big figures. Very often on the case of a chamber the digital zoom which is recommended to be used only in browse mode of the image when it is necessary to check in more detail the image is specified and to check the received result for quality (sharpness, specification, lack of noise). Also, depending on lens FR, its opportunities, namely viewing angle and its range change (how far it can bring closer remote object). The value of focal length is less, the viewing angle and vice versa is wider.
Depending on the purpose which is set before himself by the photographer it will apply different types of lenses. For example, the wide-angle type of a lens (the FR small value of 24 - 28 mm) is suitable for landscape pictures and shooting of interiors, apply dlinnofokusny type of a lens (great values of FR of 200 - 400 mm) to shooting of remote objects etc. For yourself note, the more value of frequency rate of a zoom of a lens, the its opportunities are wider, namely, with such lens it is possible to remove landscapes, portraits, sport, the nature and that is important - macroshooting (provided that it is a chamber with not interchangeable lens).
Apparently, at change of focal length there is a change not only a lens point of view, but also change of prospect of a picture. Increase in focal length (200 mm) does a background to larger (brings closer remote objects), “conceals“ a difference in distance to forward and back plans, does prospect of more flat. At reduction of focal length (24 mm), the place of large details on a background is taken by a panorama, and the background becomes visually farther, more small and more accurately, thereby, strengthening feeling of prospect on the image. At focal length of 50 mm prospect of the image such is as sees our eye. The fact that if we stood still the photographer, we saw the same image which is shown in the photo with focal length of 50 mm means.
Svetosila - ability of a lens to transfer image brightness. Svetosila of a lens is characterized by degree of openness of a diaphragm we Will consider on the example of 1:2,8 - 4,9 where are 2,8 and 4,9 diaphragm numbers which show the maximum degree of openness of a diaphragm, respectively on the minimum and maximum focal length (7,8 - 23,4 mm). The diaphragm is a petal mechanism in a lens of a chamber which allows the photographer to adjust brightness of the image or quantity of a light stream which gets through a lens on a matrix.
Apparently, each degree of openness of a diaphragm (still call a relative opening of a lens) is characterized by diaphragm number. The value of diaphragm number is less, the diaphragm and vice versa is open more. The less first diaphragm number (in our example this number 2,8), for example 2,6, 2,0, the high-aperture will be considered a lens. It means that in the conditions of bad illumination (relatively), it is possible to do pictures with such endurance which will not lead to vague images.
finally to understand as images turn out, we will consider several terms. The photo (from Greek: Photos - light and grapho - I write) - drawing by light. A conclusion, the image appears thanks to a light stream which has to get on a photosensitive element, at the same time a certain quantity.
The quantitative measure of light which needs to be passed on a photosensitive element (matrix) to create the image is called an exposition. The exposition, that is a certain amount of light, is regulated by a ratio of a diaphragm and endurance. Endurance - time during which light influences a matrix (film). Excerpts happen short and long. And the last, the modern digital camera thanks to the processor a chamber automatically measures an exposition (i.e. that amount of light which needs to be passed on a matrix, at the same time having established the necessary diaphragm and endurance) depending on external conditions of lighting.
View-finder. In film chambers it is possible to pack a shot only using the optical view-finder. Digital cameras allow to forget about it as in the majority of models it is for this purpose more convenient to use the display at all. In some very compact cameras of the view-finder is not present at all - just from - for the fact that there is no place for it.
the Most important in the view-finder - that through it can be seen. For example, reflex cameras so are called just from - for features of a design of the view-finder. The image through a lens by means of system of mirrors is transferred to the view-finder, and thus the photographer sees the actual area of a shot. During shooting when the lock opens, the mirror blocking it rises and passes light on a sensitive sensor. Such designs, of course, perfectly cope with the tasks, but take very many place and therefore are absolutely inapplicable in compact cameras.
In compact cameras use optical view-finders of real vision - it is a through opening in the chamber case. Such view-finder does not take a lot of place, but its review does not correspond to what “sees“ a lens that leads to effect of “parallax“. Still there are pseudo-reflex cameras with electronic view-finders. The display to which image is transferred directly from a matrix - as well as to the external display is installed in such view-finders small.
Effect of parallax - effect of discrepancy of borders of the shot observed via the view-finder and the shot formed by a lens on a film. Arises owing to discrepancy of axes of the view-finder and a lens of the camera.
Advantage of digital cameras with existence of the view-finder (benefit for future user) consists that they are more economical in energy consumption (on condition of the switched-off display), and also its use in the conditions of bright and insufficient lighting when on the display practically nothing is visible.
Flash. Flash, pulse light source, is used, as we know, for illumination where it is not enough main lighting. The built-in flashes usually not really powerful, but their impulse is enough to light the foreground. On creative and professional chambers there is still a contact for connection of much more powerful external flash, it is called “a hot boot“. Flash modes:
• AUTO - the automatic mode. In this mode the chamber itself defines when flash, and when there is no, depending on external conditions of illumination is necessary.
• Mode of compulsory flash. Regardless of illumination conditions flash is constantly included. It is used at kontrovy light for elimination of a shadow on object of shooting.
• Mode of suppression of effect of “red eyes“. The effect of “red eyes“ in a picture arises owing to flash application when the light stream from flash gets into inside eyes on his retina (the retina of an eye has red color), there is a reflection which is fixed by a chamber matrix. Apply a series of preliminary flashes before the main stream of flash to reduction of this effect owing to what the pupil of an eye is a little narrowed in the diameter, reducing this effect. The second way of elimination of effect of red eyes - program (function of a photoshop), the third - technical which sense in that to lift flash as it is possible further from a lens axis. In such chambers where flash is lifted, the reduced effect of red eyes is observed.
• The mode for shooting at night. Flash, further depending on illumination conditions some hold time for exhibiting of a background in the photo. At the same time it is necessary to consider a possibility of effect of “shevelenka“, in other words, of unsharp photos from - for tremblings of hands of the photographer at long endurance. It is recommended to use a support at this mode of shooting.
Power supply. In digital cameras AA format batteries (finger-type) or lithium - ionic accumulators are the power supply. In turn batteries of the AA format happen salt (R), alkaline (LR), Ni - Mh and Li - on. Salt finger-type batteries (AA R06) in a type of the low power in digital cameras are not used.
Advantage of finger-type batteries consists in their low cost and prevalence (benefit). As for lities - ionic accumulators, their advantage in dimensions and weight that gives you easier and compact digital camera (benefit). But this power supply (Li - on) is not recommended if you plan to use a chamber in places where there is no opportunity to recharge the accumulator for a long time of use.