Technical question about sensor density x resolution

[BBear]

I'll keep it short and direct.


Assuming a DSLR APS-C 10MP 4MP/cm².


I believe when you reduce the output format to 5MP, the camera still uses the complete sensor @ 4MP/cm² and then resize to the desirable 5MP.


Why note reduce the density to 2MP/cm² (i suspect it is not linear math because of the area squared, but let's keep this way to simplify numbers) over the full sensor area and get the desirable 5MP output?


Wouldnt the quality be better if you reduced the density? How does that work?

[RBellavance]

To alter the density, you would have to physically rearrange the photosites on the sensor. Besides, a lower pixel density by itself is not a garantee of better image quality.

[BBear]

should I patent the idea or not?