Digital Cameras Telephoto Lens
Can someone please explain focal length for digital cameras?
I have an Xti and I want a decent but not to expensive portrait lens for my camera. I have been told that a 50mm lens is actually 80mm with my camera. Is this true? How about telephoto lenses is a 200mm actually 230mm? Or does the difference increase or decrease with short-long focal length lenses. Is there a formula equation or something?I am so confused. I went from a film slr to digital and the transition has left me confused. If anyone can give me a good answer please do.
Because the image sensor size used in digital cameras are of different sizes, the same focal lengths may be expressed using different numeric values. Smaller image sensors require smaller lenses; larger image sensors require larger lenses to ensure all the surface of the image sensor is covered. Other factors, such as amount of optical zoom provided, may further affect the distance between lens and image sensor.
By using the 35mm equivalent, we simply make it more convenient for everyone to use a handy reference point. Most, if not all, camera manufacturers will list the 35mm equivalent in the specifications of a digital camera. Interestingly, some digital cameras are now even engraved with the 35mm equivalent on the lens barrel to express the focal length of the lens. It makes more sense in a way, though it is important to bear in mind that 35mm equivalent does not mean 100% compatibility with the real 35mm lens. This is especially true in the area of depth of field.
If you use digital SLRs (dSLRs) that use lenses made for 35mm film cameras, you need to be aware that the focal lengths expressed on the lenses must be multiplied by a factor. That factor, the Focal Length Multiplier (FLM), depends on the image sensor size used.
Of course, if the image sensor is full-frame, i.e. it is the same size as 35mm film, then the multiplier is 1, and the focal length of the lens is accurate.
However, only a few dSLRs use full-frame image sensor, with most using a smaller image sensor, usually APS size (or roughly half-frame). That is why you will read that a focal length multiplier of, say, 1.6 needs to be applied to the focal length of the lens to obtain the “true focal length.”
So, for a dSLR using an APS-sized image sensor, the focal length of a 55mm lens becomes approx. (55 x 1.6 = ) 88mm lens. This is both good news and bad news. The good news is that you can now achieve super telephoto coverage without buying costly and unwieldly lenses. For example, a 100-300mm zoom lens, with a focal length multiplier of 1.6, now acts like it was approx. 160-480mm. The bad news is, of course, that your 18mm super wide-angle lens is now acting as though it were approx. 28mm, making it almost impossible to obtain the kind of super wide-angle coverage that most professionals desire.
I hope this helps.
Using Camera Lenses : Using Telephoto Lenses
|
|
Sigma 55-200mm f/4-5.6 DC Telephoto Zoom Lens + Hoya 55mm UV Haze Protector Glass Filter + Sigma Spudz XL Microfiber Cleaning Cloth – for Nikon Digital SLR Cameras including Nikon D50, D70, D70s, D80, D100, D200 & D300 $229.99 Kit includes: 1) Sigma 55-200mm DC Telephoto Zoom Lens; 2) Sigma Spudz Microfiber Cleaning Cloth; 3) Hoya 55mm UV Protector Filter. ♦ Sigma 55-200mm Lens includes: Front & Rear Lens Caps; Lens Hood; Soft Case; Instructions; Sigma USA Warranty. ♦ The Sigma 55-200mm is a lightweight, compact 3.6X telephoto zoom lens exclusively designed for digital SLR cameras featuring the standard APS-… |
|
|
3 in 1 Camera Lens Kit for Apple iPhone 4 iPad (Fish Eye Lens, Wide Angle + Micro Lens) $12.99 Feature: 180 Fish Eye Lens 1. Fish-eye lens 180 degree angle 2. Lenses range between 15.8mm-25mm diameter x 6.5mm-15mm length 3. Compatible with any phone camera with lens smaller than 9.5mm 4. Will cover the flash on an iPhone4 Wide Angle Lens (+ Macro Lens) 1. Compatible with any phone camera with lens smaller than 9.5mm. 2. You can use this conversion lens to make the wide angle shots as 0.67… |
|
|
185° Super Fish-Eye Lens Magnetic Mount for iPhone 4 4S iPhone 3G 3GS ipad 2 i9100 HTC DC112 + One Cool Skull Key Chain Charm Strap At Random Color $22.59 Features: Brand new and high quality; 185 degree Telephoto Conversion Lens for iPhone, iPad 2; Easy install and instant on and off for quick changes; Includes flat adhesive metal ring that is fixed around the original lens; Strong magnet keeps the lens in place; Made of top-grade aluminum and high quality glass; Also compatible with other digital cameras, mobile phones and PDAs Specificati… |
|
|
Tamrac 697 Big Wheels Rolling Backpack LP7 (Black) $449.95 Big Wheels Rolling Photo Backpacks The Big Wheels Rolling Photo Backpacks, Models 697 and 698, combine the advantages of a wheeled camera bag and a photographer’s backpack in a unique, highly protective camera case. Designed for photographers who must carry a lot of equipment in diverse situations, the Big Wheels Rolling Photo Backpacks have oversized, ball-bearing wheels and telescoping handles … |
|
|
Camera Order $19.99 4+~~Practical Applications~~Starr Whitesides~~http://itunes.apple.com/app/camera-order/id442883647?uo=5~~Practical Applications 2011~~1.3~~4174474~~1158481~~~~http://www.practical-applications.com |
|
|
Fujifilm FinePix S4200 14MP Digital Camera, 24x Optical Zoom, HD Movie Recording – Black $203.95 The FUJIFILM FinePix S4200 Digital Camera bridges the gap between the point-and-shoot and DSLR realms in a number of ways. It’s compact, yet features a useful hand grip. It boasts a 24x optical zoom lens, an electronic viewfinder, and a 3.0″ LCD, among other great attributes – including 1280 x 720 high definition video capture. At the same time, the S4200 keeps things simple in small ways, such as AA alkaline battery power and a super-fast start-up time of 1.8 seconds. The Fujinon 24x optical zoom, 24-576mm wide angle zoom lens gives you the flexibility to shoot close-up or super telephoto, capturing distant subjects with ease. The lenses’ Super EBC coating – the same process used for Fujinon broadcasting video lenses and large format pro cameras – reduces ghosting and lens flare, for clean, crisp images. The aforementioned 24x zoom also utilizes a 42-step electronic powered zoom control for smooth transitions. Additionally, in macro, the lens can capture subjects as close as 2cm (0.7″). Of course the S4200 also packs in all the great simplicity of a point-and-shoot with its many auto modes and functions. Six Scene SR AUTO modes – including Portrait, Landscape, Night, and then some – along with a bevy of other options, take the guesswork out of shooting, giving you great images each time you shoot. Another example of a great function of the S4200 is the Natural Light and With Flash function, a mode that takes both a natural light image and one with flash, as the name so aptly suggests. When you can’t decide which way to go, shoot both. Save both images or only keep the one you like best. Either way, you’ll get to see the image both ways and decide for yourself. When you’re finished shooting – whether you captured stills or videos – FUJIFILM makes it easy to share your memories. There’s the option to tag files in-camera for instant social media sharing upon connection to a computer, and there’s the MyFinePix Studio which automatically searches for new images to upload when you connect the camera to your computer as well. Additionally post-production functions include Photobook Assist and a number of useful playback options like Micro Thumbnail View, slideshow, and red-eye removal. |
|
|
Nikon 1 J1 Mirrorless Digital Camera with 10-30 mm & 30-110 mm Lens – Silver $696.95 Nikon’s 1 J1 Mirrorless Digital Camera with 10-30 mm & 30-110 mm Lens features New super high-speed AF CMOS image sensor and offer focal plane phase detection AF, Smart Photo Selector for simple capture of the best shot & high quality images, with the interchangeable option you can expand your creativity with the 1 NIKKOR Lenses. Nikon 1 J1 for the freedom to capture, communicate and connect to life. Bring quality, depth and passion to visual storytelling and spark conversations through photos, movies and multimedia. Your zest for life is fueled by a desire to communicate all that you experience. Share the very incredible world that is yours with The 1 NIKKOR VR 10-30mm f/3.5-5.6 which is included is a CX-format standard zoom lens captures sharp details with up to three times magnification. Compact and lightweight, the 10-30mm is equipped with Vibration Reduction (VR II) and a silent stepping AF motor (STM) which make it the ideal, versatile lens. Quality and integrity are hallmarks of the new 1 NIKKOR lens system. The 1 NIKKOR VR 30-110mm f/3.8-5.6 which is included ha a maximum aperture range of f/3.8-5.6, this CX-format compact telephoto lens captures every fine detail, making it ideal for a wide range of scenes, including sports to portraits. Compact and lightweight, the 30-110mm is equipped with Vibration Reduction (VR II) to keep moments sharp. Quality and integrity are hallmarks of the new 1 NIKKOR lens system. The J1 and V1 are the world’s first interchangeable lens digital cameras equipped with focal plane phase detection AF*3 for the world’s fastest autofocusing*4. They offer standard sensitivities of ISO 100 to 3200, with the ability to further increase sensitivity to an equivalent of ISO 6400 with a Hi 1 setting. They also support matrix metering, center-weighted metering and spot metering. |