Sunday, March 13, 2011

Hasselblad - Ferrari special edition

Digital cameras are available in many shapes and sizes. If you spend the required amount of extra cash, you could even pick up a special edition version, like the Ferrari-edition Hasselblad camera pictured above, but point-and-shoot digital cameras have become so cheap and accessible that almost everyone has one. Almost every mobile phone has a camera of some sort, these days. While these smaller options have become common place over the last decade or so, larger dSLR cameras have started entering the budget range of a many consumers. Canon started the trend with their compact and affordable 350D. Nikon was soon to follow, and now there are many options in the entry and mid-level dSLR market.

Though prices may have dropped, dSLR cameras are still quite expensive. Yet many are willing to pay several times the price of a handy point-and-shoot just to buy something big and bulky. Why do they do this? In our previous article introducing Digital Photography, we told you a little bit about the basic settings and features of digital cameras. Today, while telling you all about dSLR cameras, we’ll look into a few more aspects of photography. You know the drill by now - click that little “Read more” button below.

What is a dSLR camera and what makes it special?

dSLR stands for digital Single Lens Reflex. Before we explain what that means, lets go back to the pre-digital film era. Back then, most cameras had two lenses - a main one for the film and a smaller one for you to look through (viewfinder). This meant that what the film ‘sees’ is not necessarily what you see. Your photos may end up quite different from what you saw through the viewfinder. SLR cameras fixed this issue by using a single lens. Light enters through a single lens and a mirror inside the camera reflects the light to the viewfinder for you to see. When you take a picture, the mirror momentarily moves out of the way, letting the light fall on the film.

If you've got three minutes to spare, check out the video below to understand the basics

Nowadays, SLR camera’s single lenses are no longer anything special, since almost all cameras have only one lens. LCD screens have replaced the viewfinder. No more squinting and sticking the camera in your face! However, SLR cameras have a few other features that set them apart. Lets look at some of them.

Sony Alpha 33 dSLR camera - Transclucent mirror technology

Better Image Sensors

The image sensor is like the retina of an eye. It is the part of the camera that actually “sees” the image, converting light into a digital signal. Needless to say, a better sensor will get you better pictures. When it comes to sensors, bigger is better! The bigger the sensor, the more area for light to fall on. SLR cameras have considerably bigger sensors when compared to point-and-shoot. The Canon PowerShot SD1400 IS, which is a fairly good point-and-shoot camera, has a sensor that’s only 6.18 x 4.55 mm (0.28 cm²) and it takes 14.1 mega-pixel photos. Entry and midrange dSLR cameras have an APS-C sensor, like the Nikon D3100’s 23.1 x 15.4 mm (3.54 cm²) sensor which is quite larger than those found in point-and-shoot digital cameras, but the images produced are only 14.2 mega-pixel (You see why we keep saying the the mega-pixel count does not matter too much?). That’s a sensor that’s almost thirteen times bigger, producing same-sized photos - resulting in more light per inch for the photo. High end cameras like the the Canon 1Ds has a Full-Frame 36 x 24 mm (8.64 cm²) sensor, producing 21.1 mega-pixel images. That’s more than thirty times the size of the point-and-shoot’s sensor!

Sensor size scaled comparison of digital cameras

Sensor size scaled comparison of digital cameras

So what are the advantage of a bigger and better sensor? The two biggest advantages are sharper images and better low-light sensitivity. Images taken by even low end dSLRs will produce sharp images that can be used at the their native resolution. They also perform much better in low-light conditions. While most point-and-shoots have acceptable image quality only at ISO 200 or so, most dSLRs perform well even way above ISO 800. Point-and-shoot cameras have to use flashes for indoor photos, making the photo all washed out with white light. A dSLR however can use just the ambient light to produce a much more natural looking photo with depth.

Using a flash over-illuminates the scene unevenly

Using a flash over-illuminates the scene unevenly

A good sensor lets you take pictures using even low ambient light

A good sensor lets you take pictures using even low ambient light

Even on a very brightly lit day, a dSLR produces sharper images. Both inset images above are at 100% zoom.

Even on a very brightly lit day, a dSLR produces sharper images. Both inset images above are at 100% zoom.

Interchangeable lenses

The ability to change lenses makes a dSLR camera very versatile. While most dSLR cameras come with a standard 18-55mm zoom lens, there are many types that you can try. Telephoto lenses let you zoom in on things far away. Macro lenses let you focus on small things very close by, like an insect inches away from the camera. Wide-angle lenses, as the name suggests, gives you a wide angle of view. Some lenses have large apertures that are great for low-light shots.

Lenses for dSLR cameras

Lenses for dSLR camerasLenses for dSLR camerasLenses for dSLR camerasLenses for dSLR cameras

Aperture Control

SLR cameras let you control the size of your aperture. The aperture is the size of the hole through which light passes through in the lens. The main purpose for adjusting this size is the depth-of-field. In other words, you can control how much of the scene is in focus. A smaller depth-of field (larger aperture) lets you focus on just the subject and blur the background. If you have objects at different distances and want everything to be in focus, you need a larger depth-of-field (smaller aperture). This has other consequences. A smaller aperture means less light entering your camera. This can be a problem in low-light conditions. On the other hand, a smaller aperture produces a sharper image. Thus it is a balance, and a dSLR lets you choose precisely what kind of picture you want, and how the balance should tilt.

Large aperture (f/1.8) and faster shutter speed (1/45 sec)

Large aperture (f/1.8) and faster shutter speed (1/45 sec)

Small aperture (f/22) and slower shutter speed (3 sec)

Small aperture (f/22) and slower shutter speed (3 sec)

Point-and-shoot cameras also have apertures. But they are so small that their depth-of-field is always very large.

Shutter Time Control

While some point-and-shoots allow you to choose how long you want your camera’s shutter to be open, none of them can give you the control as a dSLR allows. If you want to capture a bird flapping its wings, you need a higher shutter speed like say 1/1000 sec. If you want to make a waterfall look like a dreamy stream of white, you need your shutter to be open for several seconds. Most dSLRs let you keep it open for however long you want, that is atleast until your battery dies.

Taken at 1/3000th of a second to capture the surf in motion

Taken at 1/3000th of a second to capture the surf in motion

4 second long shutter exposure to capture car headlight streaks

4 second long shutter exposure to capture car headlight streaks

Better Auto Focus and Metering

dSLR lenses come with focusing systems that are much faster and more accurate than point-and-shoot cameras. Metering refers to the camera’s system that determines and adjusts the scene’s lighting. While most camera do these automatically, dSLRs do them quicker and better. They also allow you to manually adjust and tweak these settings to get the perfect picture.

RAW Format

We are all used to our cameras creating JPEG files. Even many dSLR owners stick to the JPEG format. But if you truly want the best images, RAW is the way to go. All dSLR cameras can save your snaps in RAW format. Let’s look at why RAW is preferred over JPEG. All digital cameras take the signal from the image sensor, process the data and convert it to a JPEG file. This has drawbacks. While processing the data, your camera will apply a white-balance (what it thinks should be white), noise reduction, contrast adjustment and so on. The result of all these adjustments may not always be accurate or what you like. Then there’s also quality loss during conversion to JPEG images. RAW images on the other hand, are files that contain the unprocessed digital signal that the image sensor sends. Thus it is exactly what the sensor sees without any processing. These files can then be processed on the computer manually exactly to your liking. Adobe Photoshop running on a computer can do a far better job than the tiny processor on your camera.

Battery Life

While the battery life of most point-and-shoot cameras has been increasing over the years, they are still well behind dSLR cameras. One full charge of the camera’s battery can get you about 500-1000 snaps depending on your dSLR model and make.

Accessories

There are a lot of accessories available for dSLR cameras. Flashes, stands, lenses, filters, triggers, lights are just a few of the available ones. With such a wide variety of tools and toys to play with, the only thing stymieing your photographic creativity is you!

dSLR accessories dSLR accessory - Remote trigger dSLR accessory - Remote trigger dSLR accessory - Flash

Limitations or disadvantages of buying or owning a dSLR

We can’t mention all of a dSLR’s pros without mentioning the limitations. Most of these limitations are subjective to your personal preferences and tastes, but we’re listing out what we can identify as possible deterrents.

Size and Weight

We don’t need to say much about this. a dSLR will end up being a separate piece of luggage that you need to babysit. A point-and-shoot will fit snug in your pocket. If you don’t believe us, the images below of the high-end Nikon dSLR and a point-and-shoot should suffice.

Size comparison between a Nikon dSLR and a Nikon Coolpix cameras

Price

This is probably the biggest con and is usually the deal-breaker. With the cheapest entry-level Canon EOS 1000D starting at an MRP of Rs. 25,295/-, dSLRs are not cheap. A decent midrange dSLR will cost you atleast Rs.35-50,000. Additional lenses and accessories can and will end up costing more than the camera itself. Though there are some who like to have huge kit bags with several lenses, we’d recommend atleast three different types, to make full use of the dSLR. This could end up costing you anywhere from Rs. 1 lakh to over Rs. 2 lakhs.

Conspicuousness

This may not be a limitation for some, but you will attract attention with a dSLR camera. Whether you’re at a tourist attraction or a wedding, walking around with a big camera around your neck will get you noticed. If you like keeping a low profile, dSLRs are not for you.

While point-and-shoots and dSLRs have been sitting at the opposite ends of the spectrum, manufacturers are now coming out with cameras that fall in the middle. Perhaps the most successful compromise are the micro four-thirds cameras. These have body sizes comparable to some point-and-shoots, yet they have interchangeable lenses and image sensors that are almost as big as dSLRs. These might be a good option if you want the best of both worlds. However these cameras are still quite expensive.

Sony’s NEX-series camerasSony’s NEX-series cameras

Sony’s NEX-series cameras

At the end though, if you enjoy photography or just want good pictures, a dSLR would be worth the money and effort. If you just want a unobtrusive handy camera and aren’t too bothered about near-perfect image quality, a point-and-shoot is a no-brainer (a good camera in a mobile phone, such as the one present in the iPhone 4 or the N8 may also do).

2 comments:

Barney said...

When speaking about lenses, a telephoto lens is different from a zoom lens. Now, the difference is with a telephoto lens (400mm), one can view the image/subject only at 400mm from the camera. No zooming done here, technically as the focal length is fixed whereas it is with the zoom lens (200-400mm) you actually zoom in between 200mm and 400mm.

The Indian Geek said...

Hello Barney, and thanks for taking the time to share your thoughts. We do agree that telephoto lenses strictly don't "zoom", but in today's world, most telephoto lenses do also provide zoom capabilities, such as this line from Sigma http://www.sigmaphoto.com/shop/telephoto-zoom-lenses

Basically, a telephoto lens employs technology to reduce the length of the lens, so that long-focus lenses can be shorter than they would otherwise need to be. We really didn't think that our basic primer on dSLR cameras and their advantages over compact digital cameras would be the place to get into the nitty-gritty details. Nevertheless, thank you so much for pointing this out. Good to see people out there who know their photography.

Thanks.

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