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I work at a camera shop (in Texas) and people who are very ignorant about technology come in and they say "I need a camera with a lotta 'megapeixels'" (southern accent included).
I try to tell them that they only need a high number of megapixels if they
1. want to take a big picture (physically)
2. want to be able to zoom in to different parts of their pictures (detail)
3. have a high resolution computer monitor.Now my roommate is trying to tell me that the more megapixels a camera has, the higher quality the pictures will have. This is really getting on my nerves.
Correct me if I am wrong, but I do not think the resolution that the camera is set at determines the actual quality of the picture; the DPI does not change with the resolution. A computer monitor is what determines the DPI.
Am I wrong?
Just as the higher monitor resolution creates sharper images so does higher resolution in a digital image. Just as higher resolutions and more color depth require more graphic memory, digital cameras require more pixels to yield sharper imaages. Just as going to higher resolutions and refresh rates yeilds less and less improvement after a certain point, so does the pixel count on a camera yield dimimishing returns after a certain point. Most expert state that unless you are printing to large formats, 3/4 megapixels is adequate. I just bought a cheap (real cheap) miniformat digital camera and tried to magnify shots. The pictures pixellated so bad at 2x to 4x that they weren't identifiable.
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Yea, like I said that's only if you have the higher resolution monitor though. I also feel that three MP is adequate for the time being, until the DPI on monitors increase substantially.
Also going along with what you said, scanning an image at above about 96 DPI yields basically no advantage, at least with the technology that is on the market today. I found that Windows simply stretches the picture out, spanning it across the set pixel ratio (for the OS) on the screen, essentially making the picture larger.
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Chad, You and your buddy are arguing about apples and oranges. More camera pixels means better resolution like your friend says, but everything that you said is more or less true also.
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"three MP is adequate"
I agree with that. but if you use a cheapo 0.8 MP camera and try to crop out the part you want to keep from the center and then enlarge it, it will look crappy. An advantage of a higher MP camera is the ability to crop parts of the picture and then enlarge. Doesn't work so hot on an entry level camera.
Tell your next customer..
"Ah know jus wut y'all need. This here camera has more pixels than patties in a pasture. Mah granpappy jus got one to take pichers of the lil' 'uns with."
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Haha that would be funny. I respect what you guys say, and I am just trying to obtain a correct understanding of this subject.
My sister has a one-megapixel camera, and with it a picture can be taken at 320x240, or it can be stretched out to 640x480. At 320x240 (1 MP), the picture is quite clear. Of course at 640x480 the picture is pixellated since the camera stretches it. On most digital cameras, there is a setting for image quality, apart from the resolution. With the way that JPEG's are encoded, this determines mainly the number of colors present in the recorded image. So, going down to 1 MP at the highest quality setting (not resolution) should yield the same quality as any other camera, but not the same size.
I have another question. What does it mean when the camera's resolution is set at 1536x1024? Does it mean that there are 1536x1024 dots per square-inch, or does it mean that the image is this many dots in width and height?
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Ok, I just don't know. I called Canon USA and asked if a picture is taken at 1024x768 with a 2 MP camera vs a 5 MP camera, they said that the 5 would yield a better quality picture. I'm just going to have to think about it. It does make sense, but I have to put everything together that I know.
Thanks for your responses!
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more megapixels = better everything.
its like using 110 film versus 35 millimeter.
even at a 3x5 print, the larger capture area (35mm) "soaks" up more information.not to mention printing. megapixels is everything in a quality print. not everyone just captures for screen resolution. especially photo store customers. dont sell em a camry when they could have a lexus.
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ok ok I got it now. I did some research and here it is:
The resolution on a camera is a measure of the number of dots in the x and y directions. This is not a measure dots per square inch (DPI), but rather it is a measure of the width and height for the entire picture.
The DPI on a printer is how many recorded dots it can put into one square inch. Printers resize images to fit the selected print size, and this does not change the image’s quality.
The undistorted size in inches of a printed digital image can be obtained by dividing the x and y resolutions by the DPI on the printer.
For example, an image that has a resolution of 1600 x 1200 printed with a printer that has a DPI of 160 will yield an image that is 10 inches by 8 inches.
A one mega-pixel image contains one million recorded dots in the entire image. As the number of mega-pixels increase, the size of the picture increases, not the quality.
A higher number of mega-pixels does not necessarily increase the quality of an image on a computer screen. More mega-pixels produce a larger image. This provides more detail in a picture, which allows for larger cropping on a computer. Most computer monitors today are only capable of displaying 96 DPI, whereas printers today can produce printed images that have approximately 300 DPI. Therefore, the quality of an image, taken at the highest quality setting, is limited by DPI.
Resizing an image from a very high resolution, taken at the highest quality, to a smaller resolution will NOT increase the quality of the image.
Changing the DPI of an image with a computer program will only affect the printed image. Raising the DPI will compress an image. Lowering it will stretch an image. However, no quality advantage is gained in the printed picture if the DPI is set higher than the printer is capable of outputting. Consequently, there comes a point that more dots in a picture will not increase printed image quality.
The limiting factor of the quality of a printed image is mainly the printer. The number of mega-pixels needed should be determined by how large a printed image needs to be and the quality of the printer (DPI) that the images will be printed from.
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sure, but that is not always determinable before hand. as a safety, use the most mp you can afford. there are printers capable of higher than 300dpi. if you crop an image in half, and print it on a high quality output device, you'd be glad you bought the 6mp camera over the 3 any day. left out of your research is the effect of image sensor size. a 1/2 inch image sensor will capture a better quality image than a 1/3 inch sensor-- both at 3 mp. if all you care about is screem resolution, buy a 1.3 mp for 100 bucks, and you'll be very happy. if you care about print quality (as most customers in a photo store would, i imagine), they are gonna be very disapointed with the same 1.3 camera. unless they print full frame 4x6 only-- but someones always gonna wanna crop that 11x14 sometime...
you wouldnt use a 110 camera for anything even though they make a good 3x5, would you?
obviously, it depends on the customers needs, but to say "I also feel that three MP is adequate for the time being" is asuming alot. thats like saying a PIII 1 ghz is "good enough". for who?
i have a d1x nikon for work. i much prefer to use my rolleiflex and print in a darkroom. VIVA LA FILM!
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yea i agree with you that film is better and probably will be for a long time when compared to digital.
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Im looking at getting the Sony DSC-U20
Anyone know what SXGA (1632x1224)
and VGA (640x480) Image Sizes are refering too?What would the dimentions be if it were 1632x1224 and i wanted to print at 300 DPI?
How do you convert pixels and DPI to the dimentions?
AHHHHHH
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