Quality vs Megapixels?

[chris]

Hey guys,

Newbie here with some questions that hopefully you experts can answer

I own a Sony P-72 Cybershot digital camera. In the manual, it speaks about image size and image quality. For instance, I can select from the following image sizes: 3.1M, 2.8M, 2M, 1.2M, and VGA. Furthermore, I can select the following quality: Fine, or Standard.

Kind of a dumb question, but what exactly is the difference between the size and the quality? I was under the impression that the quality of the image is determined by the number of Megapixels (3.1, 2.8 etc); however, the manual seems to give me the impression that MP determines size, NOT quality. Can someone please shed some light on this issue? Moreover, does anyone with a Sony camera know the difference between "Fine" and "Standard" ? I know this has something to do with the compression ratio, but I am uncertain as to what the relationship is.

Furthermore, I always like to develop my pictures with the postcard size. In the manual, it says that 1.2M should be used for printing postcard size images, while VGA is for creating your homepage. This may also seem like a dumb question- but, is it possible to select the size as 3.1M (in the manual it says this applies to A4 size images), and print it out as a post-card size? ie) I am thinking that if I can have more megapixels, and somehow shrink the size to a post-card, the quality will improve. Something tells me this is not right, as the quality is determined by Fine/Standard, and the MP has nothing to do with this (it only affects size, not quality).

Thanks in advance for all comments,

Chris.

[arferrari]

The MP is the size of the photo.
The Quality is the DPI(Dot Per Inch) at the photo!

So, a photo with the fine quality has more DPI.

To know what resolution is better for print the foto, there is a table...

http://www2.e-fotos.com.br/expresson...5f98e12d46#P19

see -> Com que resolu’*‚„’‚‚§’*‚„’‚‚£o devo enviar minhas imagens

[pip22]

Not really a correct explanation. The megapixel setting is related to photo size, true enough. More megapixels means a clearer picture for a given size of photo, compared to having fewer pixels which would therefore have to be larger for the same size photo -- and larger pixels means more chance they will be visible as coloured dots.

As for the quality setting -- it does NOT determine how many dots per inch. It determines how much 'compression' will be applied to the JPEG file in the camera. 'Fine' is less compressed than 'Standard', so 'Fine' will give you a higher quality picture since higher compression will throw more colour information away to make the file smaller. It's basically a case of deciding what's more important to you -- getting more pictures on the memory card (Standard setting), or getting the highest quality (Fine setting).

oh, and well done with the link --- it's all in Spanish!

[Rufford]

Actually, I believe the link is in Portugese