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This section shares and explains the information you need to decode the names and understand the basic characteristics of different types of digital SLRs available today. For example, you should be able to grasp the essential characteristics of the Nikon D3300 24.2MP DX-format (APS-C) dSLR with 18-55mm lens and how the Sony A99 24.3MP full-frame A-mount dSLT with electronic viewfinder differs from it just by reading the names.

There’s obviously a lot going on with those two names. I’ve overloaded them with extra details to show you how much information can be embedded within camera names and listings. The rest of this section will help you identify the make and model, sensor size, pixel count, lens mount, mirror and viewfinder, and kit lens details of each camera.

Make and model

Let’s start with the basic name of the camera. Each camera manufacturer has a method to its naming madness.

❯❯ Nikon starts its dSLRs with the letter D (think digital), followed by a number. In general, the smaller the number, the more advanced and expensive the camera. For example, the D5 is currently Nikon’s premier professional camera. The D3300, on the other hand, is an entry-level consumer camera.

❯❯ Canon uses the acronym EOS (electro-optical system) and then a specific model number to identify its digital SLRs. For example, the Canon EOS 80D is a mid-range model. Canon uses the term Rebel to identify its consumer dSLRs. The Rebels sport one of two model numbers, depending on the market they are sold in. For example, the EOS Rebel T6i is also known as the 750D. You may see it written as the EOS Rebel T6i/750D.

❯❯ Sony dSLRs and SLTs are identified by the letter A, followed by a two- or three-digit model number, such as the A99 or older A300. When you pronounce the name, you can say A as you would any other A, or you can say Alpha. New Sony models are all SLTs, which have translucent mirrors that do not need to move out of the way when you take a picture. The A77 II is a dSLT, although you may see it listed as an Interchangeable Lens Digital Camera (ILDC).

Sony calls its digital Single Lens Translucent cameras SLTs. They are, in essence, dSLRs with the moving reflex mirror replaced by a translucent mirror that doesn’t move. The more general acronym is dSLT. For more information on how dSLTs differ from dSLRs, jump ahead to the upcoming section, “Mirror and viewfinder type.”

❯❯ Pentax dSLRs use the letter K followed by an identifying number, such as the K-70 and K-3 II.

❯❯ Olympus has phased out its digital SLRs in favor of the popular OM-D mirrorless “Micro Four Thirds” line (named Micro because they do not have the same mirror and optical viewfinder as standard Four Thirds system cameras). OM-D (I keep wanting to write “OM-G!”) cameras have interchangeable lenses and most of the same features as dSLRs. Although I don’t cover mirrorless cameras in depth in this book, they look, feel, and act like dSLRs in most ways. The main differences that you will notice are that they are smaller and thinner than most dSLRs. Like dSLTs, whose mirrors don’t move, cameras like the OM-D E-M10 do not “clunk” when you take a photo. There is no mirror to move. Older Olympus dSLRs are designated by the letter E followed by a number, such as the E-5.

Sensor size

Digital SLR sensors vary in size. Aside from the differences in cost and the technical merits of using a smaller or larger sensor, sensor size has a profound impact on how photos look. In effect, smaller image sensors make it look like you’ve zoomed in compared to a camera with a larger sensor. The amount is expressed as a multiplier, and is called crop factor. I have more information on crop factor in the section “Delving into Camera Specifications,” later in the chapter.

Here are the most popular sensor sizes and their crop factors:

❯❯ Full-frame: dSLRs whose image sensors are the same size as a 35mm frame of film are called full-frame dSLRs. This is the gold standard of professional dSLR quality. The aspect ratio of these sensors, and hence the photos you take with them, is the same as 35mm film: 3:2. Full-frame cameras have a crop factor of 1.0x. Nikon full-frame cameras are labeled FX.

❯❯ Cropped-frame: dSLRs whose sensors are smaller than a 35mm frame of film are called cropped-frame, cropped, or cropped-body dSLRs. There are several types of cropped-frame sensors:

• APS-C: This is the standard sensor size for most consumer and mid-range digital SLRs. It's smaller than a 35mm frame of film, but far larger than a compact digital camera sensor. APS-C sensors have a crop factor that ranges from 1.5x (most APS-C cameras) to 1.6x (Canon). Nikon labels its APS-C cameras DX.

APS-C stands for Advanced Photo System, Classic. APS was a film format created in the mid-1990s. It had three print formats: C (classic print), H (wide print), and P (panoramic print). You chose the format you wanted using a switch on the camera. When developed, the print would come back cropped according to the setting you used. APS film cartridges were smaller and easier to load into cameras than 35mm film. APS cameras and film were quickly overshadowed by the introduction of affordable digital cameras and are not used anymore. Digital APS-C image sensors match the rough dimensions of APS film when shot in the classic format, hence the – C designation.

• Four Thirds and Micro Four Thirds: These sensors are much smaller than APS-C sensors and have a 4:3 aspect ratio. Four Thirds/Micro Four Thirds sensors have a crop factor from 1.8x to 2.0x.

• APS-H: This category is not very prevalent today. It’s a “tweener” size. APS-H sensors are smaller than full-frame but larger than APS-C sensors. They have a crop factor of approximately 1.3x.

Figure 1-2 shows an APS-C cropped-frame Nikon dSLR sitting next to a full-frame Pentax camera. Both mirrors are raised, enabling you to see the relative size of the image sensors inside them. The difference in price? About $1,700, including the lenses.

FIGURE 1-2: Comparing APS-C to full-frame.

Pixel count

You will often see a camera’s pixel count – how many pixels make up each photo – listed as part of the name. Digital camera pixel counts are expressed as megapixels (MP), or millions of pixels. Today, even new consumer-level dSLRs have 18MP or more. More advanced cameras have pixel counts ranging from 24MP to 36MP, topping out at an astounding 50MP, which rivals some medium-format cameras (the ones that cost $15,000 to $45,000).

The total number of megapixels affects your photos’ pixel dimensions and file size, as shown in Figure 1-3. The photo’s type, size, and dimension are just below the Image Quality line in this figure.

FIGURE 1-3: This camera captures photos up to 24 megapixels in size.

All other aspects being equal, the camera with more pixels will probably serve you better in the long run. While I hate to buy into the premise that more is always better, having greater resolution means that you can crop your photos and have more left over. Having more pixels can also help you fight the urge to upgrade your camera prematurely. Camera technology doesn’t stand still, and you should enjoy the one you have for as long as you can.

Lens mount

Lenses attach to the body of the camera using a lens mount. Figure 1-4 shows a close-up of the mount on a Sony dSLR. It’s pretty large, and has to be made of metal to stand up to the stresses of mounting different sized lenses. Here is a quick summary of the lens mounts that the top manufacturers use:

❯❯ Nikon uses the F-mount, which is standard on both its cropped (DX format) and full-frame (FX format) dSLRs. Nikon also uses the DX classification to identify lenses that are optimized to work on cropped-frame, DX-format camera bodies. Lenses without the DX identifier are compatible with DX and FX-format camera bodies. As a bonus, Nikon’s FX-format camera bodies can use DX-format lenses in a special “DX crop” mode. This mode uses the area in the center of the image sensor and results in a smaller, cropped photo.

❯❯ Canon dSLRs use the EF lens mount on all its cropped and full-frame cameras. Canon uses the EF-S lens designation to identify lenses that are only compatible with cropped-frame Canon cameras. All Canon dSLRs can mount EF lenses. Only cropped-frame dSLRs can mount EF-S lenses.

❯❯ Sony uses the Alpha mount or A-mount (refer to Figure 1-4). Of note, DT lenses are compatible with cropped and full-frame bodies, but images are recorded cropped on the latter. Sony E-mount cameras such as the A7R and A6300 have dSLR-sized sensors without the mirror or optical viewfinder. A-mount SLR lenses can attach to E-mount cameras with a special adapter.

❯❯ Pentax dSLRs use the K-mount. There are several K-mount sub-types that feature different contacts and autofocus drive capabilities. In addition, adapters are available to mount old screw mount Pentax lenses to K-mount cameras.

❯❯ Olympus dSLRs use the Four Thirds mount while its newer mirrorless interchangeable lens cameras use the Micro Four Thirds mount. Note that you can attach Four Thirds lenses to a Micro Four Thirds body with the proper adapter, but not vice versa.

FIGURE 1-4: The lens mount determines what lenses are compatible with your camera.

When buying lenses, confirm that they are compatible with your camera body.

Mirror and viewfinder type

Digital SLRs have a reflex mirror that sits in front of the closed shutter and covered image sensor. Its purpose is to reflect light that comes into the camera through the lens up and into the viewfinder (among other things). This is how you view the scene, and how the camera meters the light and focuses. When you press the shutter button, the mirror moves (this is what reflex means) quickly up and out of the way, allowing light to expose the sensor. When the exposure is over, it moves back into the down position.

Digital SLTs (single-lens translucent) cameras do not have a moveable mirror. They have a semi-transparent, or translucent, mirror that stays put when you take the photo. The mirror allows some light to shine through it and onto the image sensor while bouncing the rest up into the camera's viewfinder (or into another sensor that drives the electronic viewfinder). For most purposes, dSLTs look and function just like dSLRs.

Typical dSLR viewfinders are optical. You look through a prism that directs light from the reflex mirror to your eye. They work whether the camera is on or off.

Some cameras (especially dSLTs and mirrorless cameras) now use electronic viewfinders to display information. Sony's electronic viewfinders, for example, are small, high-resolution organic light-emitting diode (OLED) monitors. This type of viewfinder combines the functionality of a standard viewfinder with the LCD monitor on the back of the camera. Because you’re looking at a monitor, anything that can be displayed on the back of your camera can also be shown to you in the viewfinder. You can compose and frame the scene normally, view photos during playback, see the camera's shooting display, and use the menu system – all without taking your eye away from the viewfinder. Truly awesome.

Figure 1-5 shows the electronic viewfinder of another Sony camera. This particular model extends outward from the body of the camera a bit. Optical viewfinders don’t need as much space, and will appear flush with the body even on small cameras.

FIGURE 1-5: Whether optical or electrical, the viewfinder enables you to see through the lens.

Lenses

You can buy most dSLRs bundled with something called a kit lens. While they are not typically top-of-the-line lenses, kit lenses are decent and have enough versatility for most amateur photographers. Kits are designed to get you started with a good lens without breaking the bank.

Currently, many consumer kit lenses are standard 18-55mm zoom lenses. Depending on the camera, you may have the option of choosing different kit lenses. Very often, these alternate lenses are a step up in quality and price, and have different focal length ranges.

Turn to Book 1, Chapter 3 to learn more about lenses. You can also turn to Book 2, which covers a number of different lens types in depth.

Wrapping it up

Returning to the two cameras I mentioned in the introduction to this section, you should now understand that the Nikon D3300 is an F-mount, cropped-body dSLR from Nikon with an APS-C sized sensor. It is compatible with Nikon DX and FX-format lenses and captures photos that are 24.2 megapixels in size. It comes with an 18-55mm kit lens. The Sony A99 is full-frame A-mount dSLT. The photos it captures are 24.3 megapixels in size. It features a fixed translucent mirror along with an electronic viewfinder. The A99 is not generally sold as a kit so no lens information is listed.