Compression

Sometime high megapixel does not necessary mean good quality pictures. It also have to depend on what are the setting you choose. In your camera setting, you can select the number mega pixels to take and this refers to how big your picture size is. If you want a good quality image, there is another setting that you need to take note of. Depending on the camera models, certain model may group both image quality and megapixel into categories like “L1, L2, M1, M2,etc” or separate functions like megapixels and quality (fine and normal). If you are unsure which setting will give you a good quality picture, you can refer to the amount of pictures the memory card can store in the LCD screen. Usually a high megapixel with low compression will take up a lot of space while the same high megapixel with high compression will take up less space. Here are some pictures taken at the same megapixels but with different compression to illustrate the quality of the picture. Bear in mind if you will to do a large printout, quality is very important.

This picture shows no much different in compression from an uncompressed picture.

This picture shows a little degradation in compression. If you save the picture and zoom in and compare the above image quality, you will see some lines appearing.

As the picture gets more compressed, you can see there is an obvious degradation in image quality. Try save the picture and zoom in. You can see some pixels showing up.

If you want to edit pictures, it is advisable to save under the lowest compression rate as possible so as to prevent image loss. Alternatively you can save under RAW format if you want to do a lot of editing such as changing white balance, exposure, etc.

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