Cameras & Camcorders

[Allan-BBY Community Connector]

Digital Single Lens Reflex (DSLR) cameras

Quality of build

The main advantage of a DSLR over a standard point-and-shoot camera is its superior construction.  DSLR cameras are made of higher quality materials and are tested extensively by the manufacturer before they are released for sale.  With proper care, DSLR cameras can last a lifetime.

 

Control

The biggest reason to use a DSLR, other than the quality of construction, is the control you have over your final image.  Almost everything on these cameras can be customized to your own specific needs and shooting situations.  At first this might seem overwhelming, but with a small investment in learning, you should reap a great reward of images that are far superior to ones you had before.

 

Modes

Most DSLR cameras have a dial to access standard settings or scene-mode settings.  This is sometimes called the “PASM” dial as it generally includes a minimum of Program, Aperture-priority, Shutter-priority, and full-Manual modes.  Other possible modes include full-auto, landscape, portrait, macro, night, and action. 

Lenses

DSLR cameras allow you to use interchangeable lenses, which are more versatile and give you the ability to upgrade over time. You can usually continue to use these lenses on new camera models from the same manufacturer, provided the mount on the unit stays the same. DSLR camera lenses, like the DSLR camera bodies, are constructed better and use higher-quality materials.  

 

View

One main difference between a point-and-shoot digital camera and a DSLR is the reflex mechanism, which consists of a mirror set at a 45° angle inside the camera body that reflects the image up into the viewfinder until the image is taken. This result of viewing your images in this way is a more accurate and stable view.

Live Preview 

A number of newer DSLR cameras come with a feature called live preview which allows the LCD to be used as a viewfinder in the same way as a point-and-shoot digital camera, although you cannot use both live preview and the optical viewfinder at the same time. Live preview is helpful in some situations where it is difficult to hold the camera to your eye.  In bright sunlight it can be difficult to see what you’re shooting on the LCD screen; in this case, using the viewfinder would be advantageous.

 

Sensor

The sensor on many DSLR cameras is at least twice the size of the sensor on a point-and-shoot camera.  This means that a 6 mega-pixel DSLR will shoot at approximately the same resolution as a 12 mega-pixel point-and-shoot.  Ultimately, this will give you a much sharper image. 

 

Flash

With a DSLR camera, you can add an additional flash via hot-shoe.  The use of a hot-shoe flash can help to eliminate red-eye in your subjects, and these flashes are usually a much stronger light source, meaning it can cover subjects that are much farther away. 

Buffer

A cameras buffer is a small amount of built in storage where your image data is temporarily placed while it is being written to your memory card. By having a larger buffer in their internal memory than standard digital cameras, DSLR cameras are able to take more images before they are written onto the memory card.  This allows for more continuous shooting without interruption.

Dust

Due to the use of interchangeable lenses, dust has a greater chance of entering the camera body and adhering to the image sensor.  When changing your lenses, you should always try to do it quickly and in a dust free environment.  Never leave the camera body sitting around without a lens attached or a body cover on the camera. Some newer DSLR cameras come with a feature that automatically removes dust from the sensor.

Allan

Community Connector

Best Buy® Corporate

[frederick4848]

I have a question regarding sensor size. Based on square surface area of a compact camera (4x6mm) vs a DSLR sensor (22x15) the DSLR has 13.5 times the recording area not just 2 times as stated. With a full size sensor 24x36 it has 36 times the recording area. So megapixel resolution far exceeds just 2 times. Is this not correct or is my math off?

[railfan]

I would also add that the ability to shoot in RAW format is a huge plus over most Point & Shoot cameras.  A RAW file is basically a digital negative and allows for greater post-processing.

[Entropy]

I think it's best to say "image quality", not "resolution" in that comparison.

A 6 megapixel DSLR will have half the resolution of a 12 megapixel point and shoot - resolution is resolution.

That said, not all pixels are created equal.  The IQ of a 6 megapixel DSLR will typically exceed that of a 12 MP P&S camera, especially as you go into low-light (high-ISO) situations.  Another good comparison is that people often will say "has noise at ISO X that other camera has at lower ISO Y" - My Pentax K20D has only slightly higher noise at ISO 400 than my Panasonic DMC-LX1 has at ISO 100.  It's basically impossible at any ISO setting for the K20D to do worse than the Panasonic at 400.

[frederick4848]

Yes but, a 6mp DSLR will not have 1/2 the resolution of a 12 mp PS because the megapixel array has 13.5  times  more surface area than the PS camera.  The individual pixel sensors themselves are physically bigger on the DSLR.  If I have 12 cupcakes to fill a 4x6 pan they will be smaller cupcakes than 12 cupcakes to fill a 22x15 tray or 12 cupcakes to fill a 24x36 tray.  The individual pixel DSLR sensors themselves are larger and gather more information per pixel (thus the larger file size) than the PS camera.  This includes all aspects of the photographic information including resolution, dynamic range, color, contrast etc.  That is why a 12mp full frame 24x36 camera can make a 24x36 inch print without pixels showing where a PS can barely make a quality 8x10 on the same printer.  It's like the old 110 film cameras trying to compete with the 35mm film cameras.  Like wise a 21mp (24mmx36mm) full frame cannot reproduce what a 21mp medium format 6cmx4.5cm sensor creates.  More surface area to use gives you the ability to have a larger per pixel array which adds  up to more of everything.  Noise is an artifact by product of sensor manufacturing which varies company to company, or sensor to sensor, and which is becoming less of an  issue as the technology improves just the same way 'film grain' was once upon a time.

[Entropy]

Again, resolution is resolution.  12MP is 12MP.  File sizes (assuming the same format and compression settings) will be identical between a 12MP DSLR and a 12MP P&S.

But again, as I said before, not all pixels are created equal.  In a P&S, the limitations of a small sensor will often result in those 12 MP "going to waste" due to higher noise, and due to optical limitations.  (It's easier for the lens resolution to be better than the sensor resolution if the sensor pixels are larger.)  So while the resolution WILL be the same, there will be major differences in general image quality due to the fact that each pixel is physically larger.  Larger pixel surface area = able to collect more light = higher signal to noise ratio for a given scene brightness = higher image quality.

[frederick4848]

In conclusion I think we are nearly in agreement but resolution is not resolution.  Perhaps the definitive explanation is following: " Pixels are not just pixels and thus resolution is notresolution. There is no single standard objective quality number to compareimage quality across different types of sensors and cameras. For instance, a 3megapixel Foveon type sensor uses 9 million photodetectors in 3 million pixellocations.  The resulting qualityis higher than a 3 megapixel but lower than a 9 megapixel conventional imageand it also depends on the ISO level you compare it at.  Likewise, a 6 megapixel Fujifilm SuperCCD image  is based on measurementsin 3 million pixel locations.  Thequality is higher than a 3 megapixel image but lower than a 6 megapixelimage.  A 6 megapixel digitalcompact image will be of lower quality than a 6 megapixel digital SLR imagewith larger pixels.  To determinean ‘equivalent’ resolution is basically tricky at best... and all you can hope for isto be happy with the job your camera does for you."

Written in an article by Vincent Bockaert  for Dpreview.com

[SlimJim77]

Very informative thread, indeed