Pixels

[Milo]

Hi Guys,

When viewing different Photo Galleries, let say galleries taken by the A20 and galleries taken by the A60, Why is it that the A60 seems to have more details than the A20? My display setting is 800 X 600 doesn't this limit the pixels of all the photos and should come out just the same? I am Confused or just plain Dummy.


































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[atkinson1]

If you resize both of the images to your screen resolution (800x600) then they should have the same quality. But when you view the pictures at their respective sizes (bigger than your screen res), one will be bigger than the other, because it has more pixels.

I hope that helps.

[Milo]

Hi! Thanks very much for the reply, but I am still confused. Do you mean that they only differ in size?
I don't know but on some peoples galery same size on my screen but different quality. How come?
Thanks!

[Biff]

A couple of things going on here. The size of the image is a characteristic of the image. How it displays is between you and your browser. if you have a 6x8 pixel image, you can make your browser display it at 600x800 but it won't be very pretty!

The second thing is that for JPEG images, not all the pixels are stored. There is a thing called compression. I don't understand the guts and you don't need to, but its kinda like a zip file but approximate, and designed for pictures. Every time a jpeg image is saved, it becomes a different image. When a jpeg file is saved, it is possible to control the amount of compression. Too much, and the quality loss is noticeable. Too little and the picture is slow to display. The right amount and the loss is less than the quality of the display.

Displayed pics can be saved at different compressions. Its also possible to save a jpeg several different times and destroy the picture quality.

I'm sure there are other things that can account for quality differences, but here are two.

HTH.