Digital camera MB vs. Computer screen

[coody]

How many MP should a still digital camera have at least so the picture can be displayed clear enough in the 1280 x 800 resolution of a computer screen?

[JohnnyMalaria]

About 1.03 (1280 x 800 / 1000000)

But that's the raw resolution. The quality of the lens may reduce the effective resolution. i.e., even though the pictures has the same resolution as the display, they may not appear as sharp as they might otherwise do.

BTW, 1280 x 800 is a widescreen ratio. Most digital still cams are 4:3, so the more appropriate resolution is 1280 x 1024 which is nearer to 1.3MP.

[yoda313]

Most digital still cams are 4:3, so the more appropriate resolution is 1280 x 1024 which is nearer to 1.3MP.

That depends. I have a really old Sony 2.1mp that has a widescreen mode for pics (3:2 I think it is? anyway it comes out wide-ish).

But its true that the default won't be tv widescreen.

[JohnnyMalaria]

You're right. The typical format is 3:2 (e.g, 4" x 6" prints etc).

[aedipuss]

ok so it's not on topic - but why is everything else x (horizontal) by y (vertical), but pictures have to be 4"x6" or 8"x10" which is vertical by horizontal?

[jagabo]

Another thing to keep in mind is that a camera that produces say, 1280x1024 image doesn't really resolve every pixel. That is, you could never get a photograph of 1280 alternating black and white lines across the image. If you want really sharp images on a 1280x800 monitor you need about twice that resolution from the camera (and downsize with a sharp filter). 2560x1600 would be 4 MP.

[coody]

I tested it by a 5MP still digital camera and made a photo slide show by the Windows Movie Maker. The picture is sharp enough in a small preview screen. After I enlarged the screen to full, the picture became unclear. Is it due to the lower MP of the digital camera? If I use high MP camera, for example, 7, 9MP, will the picture become sharp in the full screen? I am trying to figure out what results in the slideshow becomes unclear after the screen is enlarged to full and how to improve the picture quality in the full screen. Does anyone know it?

[aedipuss]

some of the problem might be that not all cameras are made to the same quality specs. a 5mp low end camera doesn't have the same quality lens as a nikon or canon. the best, sharpest pictures will be produced by the best coated glass lenses. a dslr, even a low end nikon d40 will always make a better image than a point and shoot model, just because they use better lenses.

[JohnnyMalaria]

At what resolution does WMM create the slide shows? It might be that you are losing resolution at that point.

Is there other software you can use? If you can get JPEGs from the camera, you can just look at them with Windows' Preview function (right-click on the file within Explorer).

[jagabo]

I tested it by a 5MP still digital camera and made a photo slide show by the Windows Movie Maker. The picture is sharp enough in a small preview screen. After I enlarged the screen to full, the picture became unclear.

I think JohnnyMalaria is correct. WMM is making the slideshow with a small frame size -- probably somewhere around 640x480. Enlarging that to full screen will result in a blurry image.

[lordsmurf]

some of the problem might be that not all cameras are made to the same quality specs. a 5mp low end camera doesn't have the same quality lens as a nikon or canon. the best, sharpest pictures will be produced by the best coated glass lenses. a dslr, even a low end nikon d40 will always make a better image than a point and shoot model, just because they use better lenses.

Even my old Nikon D1, with it's 2.75MP sensor, with the 80-200 f/2.8 lens (a piece of $1500 glass) or any prime (such as the $100 50mm f/1.8 Nikkor) takes images that are as sharp as -- or sharper -- than most point-and-shoot cameras, regardless of the megapixels. It's all about the optics. Megapixels are what get recorded, but if you are recording through a fuzzy piece of plastic or glass, you're going to get a fuzzy image regardless.

Images can become "sharper" as they are shrunk in size -- an optical illusion. The key is to both use a good down-sampling method (such as bicubic in Photoshop), and/or apply decent sharpening filters (via Unsharp mask in PS). But if the image is too fuzzy, it will be fuzzy at any size.

[DereX888]

Even my old Nikon D1, with it's 2.75MP sensor, with the 80-200 f/2.8 lens (a piece of $1500 glass) or any prime (such as the $100 50mm f/1.8 Nikkor) takes images that are as sharp as -- or sharper -- than most point-and-shoot cameras, regardless of the megapixels. It's all about the optics. Megapixels are what get recorded, but if you are recording through a fuzzy piece of plastic or glass, you're going to get a fuzzy image regardless.

...exactly.

[guns1inger]

I tested it by a 5MP still digital camera and made a photo slide show by the Windows Movie Maker. The picture is sharp enough in a small preview screen. After I enlarged the screen to full, the picture became unclear. Is it due to the lower MP of the digital camera? If I use high MP camera, for example, 7, 9MP, will the picture become sharp in the full screen? I am trying to figure out what results in the slideshow becomes unclear after the screen is enlarged to full and how to improve the picture quality in the full screen. Does anyone know it?

WMM does resize down to 640 x 480 for some effects, then back up to your project resolution. Also, all the default templates for outputting from WMM are rubbish. They are soft and poor quality. We have students that use both WMM and photostory (much better than WMM for slideshows, btw), and we get them to use the Papa John templates for PAL resolution. The difference in clarity is night and day fromt he built-in templates from M$.

If you must use WMM or Photostory, download and install Papa John's templates for each. He also has HD resolution templates, and details on how to create your own templates.

[edDV]

ok so it's not on topic - but why is everything else x (horizontal) by y (vertical), but pictures have to be 4"x6" or 8"x10" which is vertical by horizontal?

8"x10" photos can go either way (aka portrait or landscape).

[Nelson37]

To emphasize what Johnny said, the OP is not necessarily looking at what the camera can output, but what WMM is doing with that output.

If you want to gauge the quality of the output of the camera, then look at it directly with no changes, on the intended display. Import the pics to the PC and open them full-screen in a photo program. Try more than one.