DSLR (Digital Single Lens Reflex) cameras differ from SLR (Single Lens Reflex) cameras in that DSLRs record images in digital form, while SLR cameras record the image on film. The way both cameras take photographs, however, is very similar.
DSLR and SLR cameras both reflect light that enters through the lens using a mirror so that an image can be seen in a viewfinder. However, an SLR camera uses a film made of plastic, gelatin and other material to record the image - a DSLR captures the image digitally, on a memory card.
This comprehensive video explains the difference between DSLR and SLR cameras very well:
edit Required Materials and Processing
A DSLR requires a flat memory card to store all its images in digital format. This little card can store thousands of images, and the user is able to delete any unwanted images instantly to make space for more. The card is reusable and the image can be seen instantly on camera or a computer, and can be printed right away with an external printer.
An SLR requires a roll of film usually made of a plastic strip lined with thin layers of gelatin containing silver halide crystals, which react chemically to light to form a photographic image. This chemical reaction needs to take place in a photo lab and requires a few hours to print. The film is not reusable, and can hold only upto 36 photos.
edit Picture Quality
Both DSLRs and SLRs allow the photographer to view and focus the image using the attached lens. The first DSLRs had poorer picture quality than film SLRs. Advances in digital technology, including the number of megapixels available, have almost completely erased this difference.
Shutter speed depends on the type of DSLR or SLR. Entry level SLRs typically have a speed of 1 to 1/1000th of a second; the Konica Autoreflex TC has a shutter speed of 1/8 to 1/1000. Most modern DSLRs have shutter speeds up to 1/4000th of a second, much as high end ones can have shutter speeds as high as 1/8000 and above.
edit Optical Viewfinder
Both DSLR and SLR cameras use optical viewfinders to take pictures. DSLRs can also come with LCD viewfinders, like in point-and-shoot digital cameras, which is handy for situations when an optical viewfinder cannot be used, say underwater photography.
Both DSLR and SLR cameras are similar in that they have several settings that the photographer controls, and can be difficult for beginners to use. They also require maintenance in keeping the lens and sensor clean and dust-free. DSLRs are more beginner-friendly as they allow the photographer to preview the image or take multiple images without wasting film. They also typically come with some in-built settings for different scenarios, and the user can switch to the LCD viewfinder if they wish.
On Amazon.com, DSLR cameras range from about $500 to several thousand dollars, depending on the quality. There are far less film SLR cameras available, and the cost ranges from under $100 for a second-hand basic camera to around $1000. However, SLR cameras have the added cost of film rolls.
edit Where to Buy
The Amazon Best Sellers list for DSLR cameras. Their best selling DSLRs (as of September 2013) are:
- Nikon D5100 16.2MP CMOS Digital SLR Camera with 18-55mm f/3.5-5.6 AF-S DX VR Nikkor Zoom Lens for $479.99
- Canon EOS Rebel T3i 18 MP CMOS Digital SLR Camera and DIGIC 4 Imaging with EF-S 18-55mm f/3.5-5.6 IS Lens for $599.00
- Canon EOS 70D 20.2 MP Digital SLR Camera with Dual Pixel CMOS AF for $1,199.00
And the top 3 from the Amazon Best Sellers list for SLR Film Cameras (as of September 2013) are:
- Canon EOS Rebel 2000 35mm Film SLR Camera Kit with 28-80mm Lens for $399.99
- 35mm SLR Manual Focus Camera w/ FD 50mm lens used from $99.95 and up
- Canon EOS Rebel G Film SLR Camera Kit with 35-80mm Lens used from $99.99 and up
edit Other Pros and Cons
DSLRs allow photographers to store thousands of pictures on a memory card, while a roll of film in an SLR camera can only hold about 36 photographs. DSLRs also allow the photographer to preview the image after it has been taken, and make it easy to upload the photo to a computer to edit or print.