Optical Zoom
How to tell optical zoom of a camera?
I'm looking for a Digital SLR camera, but sometimes when I look at a page for a camera on a website, I can't find the optical zoom, and this is ...
Optical Zoom
How to tell optical zoom of a camera?
I'm looking for a Digital SLR camera, but sometimes when I look at a page for a camera on a website, I can't find the optical zoom, and this is when it says the lens is included, not just the body. So is there a camera (or DSLR if it matters) or lens characteristic / statistic that would tell me the optical zoom.
Ok, so basically, if you're looking for an "8x zoom" or something, you're not going to find it. DSLRs are getting into the prosumer/professional market. The way it works is it tells you what the actual focal length of the lens is. A point-and-shoot simply tells you how many times larger the maximum zoom is than the minimum, which isn't actually that useful to know if you don't know what the minimum means.
All lenses are measured in a focal length of millimeters. The problem is, the focal length changes depending on what size the sensor or film is, so for an SLR, it's measured in relation to a 35mm sensor/film. On a 35mm camera, they are grouped roughly into these segments:
Fish-eye: anything under 18mm (It is so wide-angle that it distorts- I'm sure you've seen pictures like that... a straight line bends as it goes down.)
Wide-angle: roughly 18-35mm (Wider than the human eye will see, but it doesn't distort that much.)
Normal: 35-75 (About what the human eye sees- common lengths: 50mm, 75mm)
Medium telephoto: 75-150 (a bit more than the human eye sees, about the same as a moderate pair of binoculars)
Telephoto: 200-500 (about a small field glass)
Super-telephoto: 500+ (like a telescope)
Now, here's the catch: most consumer DSLRs (a.k.a. anything under $1000, probably) use an APS-C size sensor, which is not quite the size of a 35mm sensor. So in order to use that chart, you'll have to figure out the 35-mm equivalent focal length, and most companies will tell you what that is right out. (Typically, it's about 1.5x.) So to use that chart, multiply whatever the length of lens you're looking at by 1.5x, and then apply the new numbers to that chart.
Typically you'd get two lenses with a DSLR, a 18(or 28)-80 and an 80-200. Those cover the range from wide-angle to telephoto, so for typical shooting, you don't need anything else. Honestly, if you get those two, you'll have more zoom than just about any point and shoot.
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Optical Zoom Support Of A Camcorder
need some
information on
the zooming capacity of
a Digital camera
. The zooming option plays a vital role in
image capturing
and generating a good image. This
does not work
if we use a weaker lens. For this to optimize my shooting what is the best recommended way to
The optics (lens, zoom) influence too much on the quality of your images. About the zoom, most manufacturers indicates the
digital zoom
as well and offers value for x400! In reality we must dig into the docs and see only the optical zoom which is much lower. Digital zoom is done by electronics based on the optical zoom magnification artificial pixels resulting in a very bad quality, I also recommend to deactivate the digital zoom function and you simply optical zoom which is the only true zoom.
Zoom is often taken as the ability to approach the scene, but can also move away from the reverse (wide) This is sometimes very important if for example you want to shoot in a small room a group of such person. This is often a weak point of digital camcorders. Instead of simply studying the value of Zoom, look rather focal representing optically true zoom capabilities (distance and magnification). The Focal length is defined by a minimum value (distance) and Max (magnification).
The exposure modes are important to optimize your shooting. Camcorders offer special programs for a number of conditions (cloudy, beach, snow, indoors ...), the option of manual exposure setting is more important (manual diaphragm) for good image quality in any conditions. The autofocus. All camcorders have an auto-focus system, i.e. that the development is done automatically on a central area.
Most camcorders have great public sensitivity rather medium to low thus producing very noisy images when the light is not strong. This becomes especially annoying indoors or only use a torch or powerful sports can overcome this problem. The tri-CCD models often have a higher sensitivity. The sensitivity is highly linked to the size of photo-sites (CCD sensor unit). More than one sensor is large (size measured in inches) is more sensitive. More than one sensor pixel, the less sensitive.
The sensor size in pixels is also highly variable and influt directly on the details of your images. DV PAL defines 720x576 pixels (420 000 pixels) but few low-end camcorders offers sensors of this format. We must also consider the stabilizer digital gripe dangerously dimensions useful when the sensor is active. 600 000 pixels are sufficient so far for the video. Some camcorders offer 1 or 2 million pixels, these sizes are useful for the photo mode and such definition shall fall in sensitivity.
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Tags: art, camera, flash, optical, optical zoom comparison, optical zoom definition, optical zoom explained, optical zoom vs digital zoom, optical zoom vs mm, zoom
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