HP C20 fine/superfine?

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Hi!

Hi! Recently bought the C20, and am very pleased so far. HP doesn't get into much detailed discussion about the technolgy. Can anyone tell me how the camera changes the "photo quality" setting from fine to superfine, recognizing that the images for both are the same 1150x850 (or close)? I see that the "average file size " goes from about 140K to 400K, for fine to superfine respectively... what's going on inside the camera? Thanks, John

Thanks John

-- John Goodfellow (goodfelo@unix.asb.com), October 12, 1998

Answers

This happens in most cameras as you vary the "image quality" setting. What's happening is that the camera is "compressing" the image more at the lower quality setting. The JPEG algorithm used for compressing images in cameras tries to throw away data that your eyes are least likely to notice, starting with the finest detail and color gradations, and progressively tossing out more stuff as the compression ratio gets higher. Take some pictures with fine detail in them (pictures of cereal boxes or newspapers are good) at the "fine" setting, and look around the edges of things - you'll probably notice little blocky things that aren't part of the original image: These are the "compression" artifacts that start to show up when too much data is thrown away. (They can be hard to see at first, once you know what to look for, you'll see them more easily.)

-- Dave Etchells (web@imaging-resource.com), October 13, 1998.

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