What do you mean by, " 2 megapixel camera interpolated to 4 megapixel ".

[firefox]

I have heard this quote often that a 2 MP camera is interpolated to 3 or 4 MP. what does it accuallty mean ?

[nichomach]

OK, imagine that you're looking at an LCD screen. It has so many pixels vertically and so many horizontally; say 1600x1200. It can't actually display more than that. A camera's sensor suffers the same limitation; it only has so many vertical and horizontal pixels, so theoretically it can only capture that many. However, many cameras are capable of carrying out intelligent guesswork. Imagine the camera saying "OK, I only have 1600x1200 pixels, but if I had 2048x1600 what would those extra pixels between the ones that are really there look like?". That's interpolation; lots of scanners do it too, starting from an optical resolution of 600 dots per inch and then interpolating up many times beyond that.

[merlin2001]

i have an fujifilm camera (F401 is the model if remember correctly) that does this. uses something that fuji call superccd and is actually a 2M camera but can be used to take shots at 4M. works pretty well - images are normally fine to print at A4 size.

[killie99]

Fuji cameras do interpolation in a different manner to other digital cameras, instead of using square photo diodes arranged vertocally/horizontally they use octagonal ones arranged diagonally. Go here http://www.fujifilm.co.uk/digital/ca...2pro/index.php and click on the super CCD technology link for an explanation of how it all works.
In my experience the fuji's do interpolation extremely well, other cameras I've used have been junk. Suffice to say when it comes to interpolation you get what you pay for as you need good algorithms and a bit of computing power to get it right, something the cheaper cameras do not have,

[Butcher]

If you want good interpolation invest in a copy of photoshop.

[DanceswithUnix]

If you want good interpolation invest in a copy of photoshop.

...and a camera that produces .raw files.

Camera CCD pixels are not the same as display pixels. For a start they have more green pixels than any other colour, which makes sense as the eye is most sensitive to green. When a camera outputs a jpg, information that that the camera had is lost.

I think we are all edging towards a simple statement of "good photography costs money"

[killie99]

I think we are all edging towards a simple statement of "good photography costs money"

I must remeber that the next time I try to justify to the wife the reason why I need to replace my D70

Zak Edit: Edited the Quote box to make it work

[firefox]

Does the interpolation work on moving images, like a video clip etc.
I have also noticed that digital video recorders, in general, have CCD's with lower Megapixel counts. Why so?

[killie99]

camcorders have much lower resolution CCD's as you are only going to be replaying them on a TV or monitor, 6 mega pixels on a camcorder is a bit pointless when it'll be played back at a maximum of 1280 x 1024. I also suspect the amount of data being recorded has a bearing on the size of the ccd as the higher the resolution of the CCD the greater the computing power requirde to process the increase in data and hence the price of the end product will rise.

[firefox]

Good point. But I have seen a video clips taken from a 4 MP digital still camera and it does not look any better than the one taken from a camcorder with a much lower resolution CCD.

[killie99]

Cameras usually have the video mode restricted to a maximum of 640 x 480 hence they are no better (or are worse) than a camcorder.

[firefox]

Are there any cameras that dont have this restriction or any settings that can be done to improve resolution?

[Butcher]

You can get camcorder up to 1080p now (1920x1080), you're not going to get motion stuff much better than that really, as the data rate would be insane.