i wanna know some expressions in digital photography?

i’m gonna buy a digital camera would anyone tell me what do the expressions listed below mean?
Camera Effective Pixels-Optical Zoom-Digital Zoom-Shutter Speed-Built in Memory

Ok, here goes …

Camera Effective Pixels – Most digital cameras have more pixels that are used specifically for the image. The Effective Pixels is the count of the total pixels that actually create your image and it’s measured these days in megapixels.

Optical Zoom – as you zoom a lens it will go from a wide angle to a telephoto and bring distant things closer to you. This is done by moving optical elements within your lens. The higher the number expressed … 3x, 6x, etc … the closer distant objects are brought to you. However as you get into higher zooms you really need an image stabilizer that’s built into the lens or you need a tripod if you want to avoid the blur associated with camera shake.

Digital Zoom – This is the camera processor playing games. What it does is to magnify the middle of the image and to give you a full sized magnification of that it creates new pixels that weren’t there initially. This process is imperfect though so you’ll get muddy fuzzy images with poor quality colour. If you ever use digital zoom you’ll never do it again after you see the results. Ignore digital zoom entirely, focus only on the optical range.

Shutter Speed – There’s a cover over the sensor to prevent it from seeing any light. This is the shutter. When you’re ready to take the picture the cover opens briefly to “expose” the sensor just as film used to be exposed. The time this cover is open (the shutter speed) varies depending on a number of different factors. For your purposes however it’s important to know the range of speeds the shutter can handle. If you’re doing something at nght may want the shutter to stay open for many seconds to capture what little light there is to get you a nice picture. On the other hand if you’re trying to photograph a flying bird you want the shutter to be as fast as possible so that you won’t get a blurry shot as the bird moves.

Built in memory – in the early cameras the camera didn’t have any memory at all so it needed a memory card to immediately store the image. One problem with that was that the transfer was what slowed things down so the time between pictures was terrible. Some manufacturers solved this problem by installing memory inside the camera. With one of those the picture you take now is already stored and you’re able to take another immediately while the first one is being written to the card. Unfortunately it’s not that simple though because once the internal memory is full you get delays again as the camera tries to clear the memory by writing everything to the card. As a result if you want to take several pictures in rapid succession, it’s a good idea to find a camera with a lot of internal memory so it can hold several pictures at the same time.

So I hope that helps a little. Good Luck!

After Effects Tutorial – Expressions / Illusions — pt 1