Author Topic: Digital Camera  (Read 2698 times)

jack

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Digital Camera
« on: April 05, 2007, 06:00:40 AM »
Table of Contents
1. Megapixel (MP)
2. Different Types of Zoom
3. Optional/Manual Settings
4. Lenses
5. Shopping FAQ


1. Megapixel (MP)
There is a lot of misconceptions surrounding the MP on a digital camera. Most people still try to apply the "more is better" idea to them because that's the most logical thing to do. However, for most people anything over 4MP is overkill unless you demand high quality prints or sizes such as a photographer or graphic designer. Here's a basic breakdown on MP and there comparitive picture sizes when printed out:

3MP: 8"x10" prints
3.2MP: 11"x14" prints
4MP: 20"x30" prints
6MP: 30"x40" prints

Higher MP = Bigger picture. If there is a picture that is taken at 3MP, this means that the picture will have 3 million pixels and so on.. the more pixels, the bigger the picture is, the better quality it is at bigger sizes because there are more pixels to accumulate one space.

These are the approximate sizes for picture print-outs (at home or at a store) at these MP qualities. The only thing that will affect these conversions is if you use digital zoom with the picture, this degrades the quality exceedingly fast. Cropping is also a concern, but with a 4MP you can crop over 50% of the picture and have an 8"x10" that would look the same if you had not cropped it at all.

2. Different Types of Zoom
Optical zoom: This is the physical zoom that is produced by the lens of the camera. The higher it is, the better your images will come out without losing quality because optical zoom maintains the resolution of the pictures taken without sacrificing anything to produce a closer view. It does so by physically moving the lense within the camera. What it does during this process is adjust the focal point so that it appears as if the object or landscape is closer to you.

Digital Zoom: This is created by the computer chip inside the camera that blows up the image internally so it looks as if the picture is getting zoomed in on. Unlike optical zoom which keeps the resolution of a picture and maintain the quality, digital zoom doesn't. All it does is removes all the pixels on the outside of the picture; then it takes the pixels that are left and fits it back into the same space and thus, makes it looks like it is closer or zoomed in on.

Extended Zoom: This isn't really a special feature; all it means is that the camera offers 8x optical zoom or greater. Most camera's offer 3x-6x optical zoom and any that has more, that's where the term get's used.

One way to think of it is to When considering image quality optical zoom causes no negative effects, and digital zoom will enlarge the pixels of the photo. Always look and compare optical zoom vs optical zoom when choosing a camera, not optical zoom vs. digital zoom. Additionally, do not confuse yourself where manufacturers combine their Optical Zoom and Digital Zoom together and state something such as "12x total zoom" where there is only 4x Optical Zoom and 8x Digital Zoom. The digital zoom will not help you very much. Read between the prints and look for it's optical zoom.

3. Optional/Manual Settings
The MP rating, picture resolution, shutter speed and various other settings can be adjusted by an on-screen menu of the camera. This is granted that the digital camera has an LCD screen. If it doesn't and everything is done manually, most of the controls will be on the camera itself (dial), and certain ones can be viewed through the view finder. One thing to consider when setting the MP rating on the camera is the size of the file. With a higher setting, you get a better picture but lose two other things. .

One, it causes the camera to act a little slower when storing the larger file size (affects response time, and the time it takes for the camera to be ready to take another picture).

Two, fewer pictures can be put on a removable storage media such as Secured Digital (SD) and Compact Flash (CF) cards.

Now, if you are using a digital camera that has the option for manual settings, you might see a dial at the top with just letters or little picture abreviations. Most manufactures will include documentation and explanations for all but here is a breakdown of some of the most common ones.

Snapshot mode: Auto mode; used for taking pictures
Program mode: Here, the camera judges the shutter speed and aperture for the shot that is going to be taken; can be used for average photography skills.
Aperture mode: Manual settings for manual adjusting of the aperture; you choose aperture, camera picks appropriate shutter speed. This varies from camera to camera. An example is F3.3 - F7.4.
Shutter mode: Manual settings for manual adjusting of the shutter speed; you choose the shutter speed, the camera chooses the aperture. Shutter speed range from camera to camera so this is something you will need to find out if you plan on using this feature. An example is 60 - 1/2000 sec.
Manual mode: You choose both the shutter speed and the aperture so you are in full control.

4. Lenses
Certain companies like Panasonic, Kodak, Canon and other camera manufacturers have been producing cameras for a long time and have higher lens quality as a result. Furthermore, some lens companies like Schneider-Kruesnach (Info) and Carl Zeiss (Info are featured on certain camera models. With a higher quality lens, images will be clearer and there will be less "ghosting" (vague, blurry lights, or objects in the image) on images .

Overall, if this if your first digital camera, and are used to disposables, then a cheap, no optical zoom camera may be a good option. Otherwise, I recommend a minimum of 3MP and 3x optical zoom to start, and then find the best camera for your needs.

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Digital Camera
« on: April 05, 2007, 06:00:40 AM »