Is bigger really better? Megapixles

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I have 2 cameras, Kodak DC120 and a DC260. The 120 uses a 800,000 pixel sensor and produces a 1280X960 image. The 260 has 1.6 Mil pixel sensor and produces a 1530X1024 image. Even though it's more pixels that the 120 camera the image is larger, so does this mean that your are really getting a better quality image? I am not convinced the 260 is giving me that much better picture.

-- David N. Carlson (davidc@sportspoint.com), March 13, 1999

Answers

In general, more pixels IS better. However, you are running across the biggest problem with the Kodak DC260. Kodak has programmed the camera to have too much compression, even in that camera's "Best" quality mode, and it is lossier than it should be. People who have a great deal of experience with JPEG will tell you that for really high quality that isn't visibly less sharp than an uncompressed image,, you shouldn't use compression ratios of more than around 4-1. The DC260 in it's best quality mode, tends to compress images by between 8-1 and 10-1. In Kodak's next generation camera, the DC265, they have apparently fixed this problem. As a DC260 owner, I am hopeful that there will also be a firmware upgrade made available for the DC260 that provides the lower compression mode that will be supported in the DC265.

-- Doug Green (dougjgreen@yahoo.com), March 14, 1999.

The Kodak DC260 does have more resolution for the same size picture. If you were to take two identical pictures with the different cameras and then print them out at the same size you would see a difference especially at larger print sizes. The confusion comes from the fact that when displayed on your monitor, the picture from the 260 is displayed as a larger picture. This is because your monitor resolution is fixed at something like 1024x768 or 800x600 pixels.If both pictures are viewed at the same size on the monitor (lets say 5x7") you won't see a difference in resolution between the two because of the difference in picture vs. monitor resolution. But if they are printed out to a high quality printer, there will be a noticeable difference especially at larger print sizes.

-- Ralph Obert (REObert@aol.com), March 14, 1999.

More pixels are always better if used with the same supporting lens and software. Unfortunately there are other factors that ultimately decide the final quality but if EVERYTHING in a camera was the SAME,the CCD with more pixels WILL give you a higher resolution hence a BETTER picture. If this was not the case, large format cameras would be, well, redundant. Your task is to figure out which company or camera model can actually take advantage of these super high pixel CCDs. Many are no better with the new 2 Megapixel CCDs than before because the supporting software was pretty crummy to start with and frankly it is still crummy. I did learn that removing your picture storage chip and downloading it to your computer separate from the camera can avoid some of the software compression effects. Of course this only matters if your camera lets you shoot in an uncompressed format in the first place. On a computer monitor with the picture loaded and set at 100% each pixel in your picture is also one pixel on the screen. The more pixels in your original picture the bigger the picture on your screen ( the less that you can actually see because most falls outside your screen area hence the scroll bars right and bottom of your screen. If both were reduced to fit an area of say 5x7", the pic with mare pixels would print also with more pixels for each inch of picture (lets say 1600 pixels for the 7 inch length and the lower resolution pic maybe only 1500 or 1200 pixels over those same 7 inches. On screen these 7 inches are on a my 15" monitor (at 800x600) only 510 pixels long. No matter how high the resolution of any picture, the monitor uses only 510 pixels over 7 inches so the pictures will look very much the same. Hope this will clear some of the confusion.

-- Rinus Borgsteede (rinuspho@cadvision.com), March 21, 1999.

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