Whats a megapixel? And how many do I need for a good picture? [Archive] - AmityMama.com

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MyThreeSuns
10-17-2002, 06:33 AM
I finally get to buy my digital camera. Yaaaaaaay! Gee...I have only been wanting one for TWO YEARS!:rolleyes:
Now I just have ot make sure I get the best for my moolah. Im talking $300 max.
In fact, lets have a photo contest! Take a pic w/your camera, and post it here, along with they type of camera you have!
Wont this be FUN???

APDaddy
10-17-2002, 09:50 AM
http://www.pcworld.com/reviews/bguide/0,guid,12,page,4,00.asp

We LOVE our Olympus!

Good Luck,

APDaddy
10-17-2002, 09:53 AM
Here's some cameras:

http://www.pcworld.com/reviews/article/0,aid,104312,00.asp


:thumbsup:

For rechargeable batteries, I'd recommend getting
Nickel Metal Hydride batteries (Ni-MH)

Good Luck,

renata
10-17-2002, 04:05 PM
APDaddy gave you some basic info, now get ready for some longer explanations and math :D (if you ever really wanted to know what pixels, dpi, and megapixels mean).

A megapixel is actually a bit more than 1,000,000 pixels. What does that mean? Pixel is a "dot", a smallest unit of the picture that can be only 1 color. The more pixels, the bigger picture, and the better picture is (more pixels = more different colors, for purpose of simplicity - I'm not going to go into color depth, etc). How all of this relates to viewing images on screen and printing them: ready for some math?

If your camera is, let's say, 1.3 megapixel. What does it mean?
Usually 1.3 megapixel camera will take 1280x1024 pixel pictures (here comes the math: 1280 times 1024 is approximately 1,310,720 thus about 1.3 million pixels, or 1.3 megapixels). Average 15" monitor will be set at 800x600 pixels, 72 dpi (dots per inch) resolution, and it's dimensions will approximately be 11.1" width by 8.3" height (close to 15" diagonal). Your 1280x1024 picture @ 72 dpi (that's how monitor will display it) will look HUGE on screen - it will be about 17.8"x14.2" - larger than monitor's screen. It can be made smaller for viewing on screen, and will look awesome.

Now, let's say, you want to print the same picture. Paper has higher resolution than monitor does - that means, paper can effectively display more dots per inch than monitor does (modern monitors can normally/usually display only 72, 75 or 96 dpi - dots per inch). When you print pictures on paper, you want to print at a minimum of 360 dpi, but 720 or 1440 is better. The more dots per inch, the smoother the picture will look when printed. So, back to your 1280x1024 (1.3 megapixel) photo: If you don't enlarge it (and enlarging reduces the quality, as you cannot create something from nothing), and want a quality print, the optimum size to print it at would be:

1280 divided by 360 = 3.5"
1024 divided by 360 = 2.9", so that makes it 3.5" standard photo print at most.

(printer's resolution is a whole another topic, and I'm not going into that, so for simplicity photo resolution should be about 360 dpi for a good quality print, and printer can be set at 360, 720 or 1440 dpi - higher would be an overkill).

3.5" at most... doesn't sound enough, does it? Ok, let's say you want to print good quality 5"x7" photos.

This translates to:
5" times 360 dpi = 1,800 pixels width
7" times 360 dpi = 2,520 pixels height

1,800 times 2,520 = 4,536,000 , or close to 4.5 megapixel. Good quality 4 megapixel cameras cost a looot :) But actually, 3.1 megapixel would make *fair* 5"x7" printed photos.



Do you feel like a digital graphics expert yet? <GRIN>

BTW, megapixels is not the only thing you have to look at. Take a look http://www.steves-digicams.com - it's by far the best digital camera review site.

APDaddy
10-17-2002, 07:31 PM
Nice, Renata. She never disappoints does she? :-)

If you are going to be printing photos, you'll want the most megapixels you can get. You'll also want the best photo paper and a top notch printer.

If you just going to be e-mailing pics to friends and family and/or uploading images to a website, I think our 1.3 megapixel is more than enough. That's because it takes such a large size photo that I end up reducing the size to make it easier for my "dial up" internet friends to download it easily enough. For our Cable internet friends, I dont' have to shrink it at all. Also, for uploading to a website, you don't want the image too large either so I end up reducing the size for that as well.

...now Renata can give us the numbers.... :-)

mamateddy
10-17-2002, 09:22 PM
Just to add a note here... I have a 2.1 megapixel camera (Sony Mavica CD1000) and I take lots of pics with it to upload and share with family. I also order a lot of prints online at sites like ShutterFly.com, Ofoto.com, and DotPhoto.com and am NEVER disappointed with the quality. I tend to make image adjustments prior to upload, like lightening or darkening and cropping, and have been totally satisfied with my prints even up to 8x10 size. Most of them use state-of-the-art dye sublimation printers and print on high quality photo paper and are for the most part affordable.

HTH.

renata
10-17-2002, 09:24 PM
I'm picky ;) thus for me a 2.1 megapixel image does not produce a good enough 8x10 (4x6 - yes, very very good quality better than many 35 mm cameras, butnot 8x10). But, once again - I'm picky ;)

TalinsMama
10-17-2002, 10:17 PM
I don't know what the current price for these are now... but I really like my Kodax DX4900. It's 4 megapixels... takes great photos, very very easy to use, and was only $350 when I bought it 6 months ago... actually I got a deal and got mine for $310.
Makes great printable pics too!

arasmama
10-17-2002, 11:49 PM
I have a 2.1 and am very pleased with the print quality. I never print 8x10s though, not sure why I would need to. If you go to a store that sells cameras they will show you the difference in print quality in each pixel type. We have an Olympus with zoom and love it. I think we paid $250. Don't forget battery charger and extra batteries, plus extra photo card thingies (not quite as technical as Renata) when figuring price.

Edited to add: The picture in my sig line was taken with my digital, but uploaded at a low quality so it loads quickly.

here is one taken with the lights off:
http://www.araspants.com/images/aramonesleep.jpg

and one outside in the sun
http://www.araspants.com/images/aug02lilyarachatting.jpg