Photo cameras – the basic guide

For a few years, digital photo cameras don’t represent a caprice anymore, but a gadget anyone can afford. Considering price is one of the main characteristics customers guide themselves when buying a photo camera and the producer’s offer is really vast, especially in the reduced price category, that’s why it is really important to know what parameters to look for, to make the right decision.

The parameters below are essential if you want to buy a mainstream or an entry level photo camera, these being the categories where producers hide important features and highlight the “popular” ones, which aren’t necessarily the essential ones for the camera’s performance.

Number of Megapixels

Megapixels are the characteristic of the photo sensor that will determine the image’s final resolution. For example, a 1000×1000 px picture means 1 MPx. The number of megapixels is determined by multiplying the horizontal resolution by the vertical one. The number of megapixels is one of the frequently used characteristics to compare two photo cameras, however it is also the worst way, because the image’s quality is mainly determined by the photo sensor’s size and the objective’s quality. Same as most cheap photo cameras have the same sensor dimension, means smaller and compact pixels on its surface, pixels that will share the same quantity of light that touches the sensor’s surface. A resolution bigger than 5-6 MPx is made only for professionals, so don’t get fooled by the 10 MPx offered at $100 – $120 .

The lens aperture (the objective’s opening, which determines the quantity of light that will touch the photo sensor)

Usually, for every photo camera or objective (if we’re talking about DSLR photo camera with interchangeable objectives) there are two aperture reports specified, one for the minimum focal length and another one for the maximum focal length. Reports look like f/x, x having values like 1,2, 2.8, 4, 5.6 etc. For the mainstream and entry level cameras, f/2.8 values are typical for the minimum focal length aperture (wide) and f/5.6, f/8 for the maximum focal length (telephoto). Higher values like f/2, f/1 indicate very bright objectives, that allow more clear photos in reduced luminosity conditions or at smaller ISO values.

Optical zoom

Regarding the zoom (how much can “we approach” this subject without physically moving) there must be made a difference between optical zoom (made by lens moving and focal length modification) and digital zoom (artificial enlargement of the photo, enlargement that can be made with a photo editor software.)

The only characteristic that matters for the zoom is the optical one. The bigger the zoom, the better the details of objects beyond. We must keep in mind that if the optical zoom is too big, it means an unprofessional photo objective, that will visibly distort geometrical characteristics of the photos made at extreme values (very wide or very telephoto position of the objective’s).

Charging

What’s also important is the way the camera recharges: with AA, AAA batteries or rechargeable batteries, different from one model to another. Both methods have advantages and disadvantages: with AA and AAA batteries, the autonomy is smaller but the advantage is that you can always carry a supply of one or two pairs. And, if you use rechargeable batteries, you’ll always have to take the battery recharger. In case of rechargeable batteries different from one model to another, the advantage is that of a bigger autonomy, but in time, their capacity decreases and they must be replaced. Here’s the disadvantage: bigger price compared to that of rechargeable batteries and reduced duration.

Storage media

A last criteria is the way photos are stored. Because on the market there are over 20 memory card types, you should also consider what format uses the camera you want to buy: the more popular the format, the bigger is the possibility to use it with other devices, plus the advantage of a smaller price per gigabyte. You should look for cameras that support one of the following formats: Secure Digital (SD), SDHC, mini SD, micro SD, mini SDHC and micro SDHC. Don’t forget that mini SD and micro SD can be used in SD slots using a converter, and micro SD and mini SDHC in SDHC slots, also using a converter. Although SD and SDHC cards look the same, the first ones can be used in SDHC slots, but not vice versa.

These are the most important characteristics you have to look for when you want to buy a mainstream or entry level photo camera, professional photo cameras being a little bit more complicated, therefore I will elaborate this subject in a future article.

Tags: gadgets, photos