I have a question about image quality. Does noise in an image is depends upon "Megapixels" or on "ISO"?
Noise originates due to a number of factors, see:
Increasing the number of megapixels keeping everything else constant (sensor size, technology etc.) will increase noise per pixel, but also has the effect of making the noise finer grained which is less objectionable.
ISO does not by itself increase noise, only if you combine increasing ISO with decreasing shutter time / closing aperture.
It's [probably] worth repeating this again here...
Increasing ISO whilst keeping shutter-speed/aperture constant does not increase noise:
Here is an example, as the ISO 100 shot was underexposed, raising the ISO to 1600 yielded a much less noisy result!
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When it comes to ISO, it's a misnomer that increasing the ISO increases noise. It's doing nothing of the sort. The reason high ISO produces noisy images is entirely due to the fact that for a higher ISO, you have to cut the amount of light (signal) hitting the sensor, ultimately increasing noise ratio before ISO amplification even takes place.
Both of those factors can have an impact on noise. Of the two, the effect of ISO is the most immediately visible. All digital cameras exhibit image noise that rises as ISO increases. Depending on the camera, you may see little or no noise at ISO 100, for instance, and proportionally more as you approach the maximum ISO setting for your camera (typically 1600 to 6400 or more). There are plenty of examples of this for just about every camera on the market (reviews for each specific camera will often show examples).
Image size (megapixels) doesn't directly impact noise, but it indirectly impacts noise when you consider two sensors of the same size. In this case, all things being equal, the larger-megapixel sensor will show more noise as a side-effect of trying to "squeeze" more pixels onto a sensor of similar size. Although this can be shown in certain cases within a camera line, this factor can be difficult to pin down because cameras also often have upgraded sensor or processing technology that manages noise more effectively.
There are some great answers on this site already regarding specific aspects of noise. If you search for "noise", you'll find all sorts of great reading.
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If you raise the ISO level, you will five the photo more noise.