High MEGAPIXEL doesn't necessarily mean high clarity images!

 We all use camera in our day to day life, especially when cameras are introduced in  mobile phones. Almost every person has mobile phones, and we daily click a lot of photos, and we upload them to social media, and some photos are like memories for us. And definitely, at some point, most of us thought that, if I have had a high megapixel camera on my mobile then the photos will be of very good clarity. Let me clarify this, high megapixel camera does not necessarily mean that images will be of high clarity. People commonly refer to this as "MEGAPIXEL MYTH". 

Seeing the top image, you may get a better view of what we are discussing. Clearly iPhone 11's 12megapixel camera out-performs 108 megapixel camera in clarity. Carefully observe the previous line, I mentioned the word clarity, not sharpness.

108 megapixel image is sharper than 12 megapixel image. Clarity and Sharpness are 2 different entities. 

The main factors that effect clarity and sharpness are : sensor size, pixel size, megapixel. I placed megapixel in last because it's effect on photos is less than what we imagine.

Sensor Size :  If the sensor size is more, then it will take more amount of photons  i.e, information of a scene, and will produce a image of good clarity but not sharper image if it doesn't have high megapixel.

Now, if you zoom the picture of a higher megapixel photo, the details won't fade away easily. But if you zoom a lower megapixel image, then all details will go blur.

Pixel Size :  

If the pixel size is good, then it can gather more information, then can give good image. Just like the above pic suggests, bigger sized pixel can able to collect more photons i.e, information. Just remember, this is about pixel size, not the number of pixels.

Megapixel : Now, about the long-lasting myth we have been conditioned to suffer, the MEGAPIXEL MYTH. Now, the higher megapixel is used to increase the sharpness of the image and it's resolution. Let me explain this by a simple example.

24 Megapixel = 6000pixels x 4000 pixels. That means, it's like a rectangular plate with length 6000 units and breadth 4000 units. By seeing the image below, you can get a better clarity.

The main advantage of having high megapixel is, we can crop the image without losing much details. Like we discussed earlier,

24 megapixel = 6000pixels x 4000pixels

13.5 megapixel = 4496pixels x 3000pixels

We can crop the 24 megapixel image more effectively than 13.5 megapixel image.

Some points to be noted : 

1.) If sensor size is same, then higher megapixel is a good addition to that.

2.) If megapixels are same, then higher sensor size is a preferable one.

Higher megapixels such as 108 MP is not of great use. Most of us even can't find the difference between 16MP image and 108MP image, unless you zoom the both images extremely, like 4 to 5 times. No one zooms images to that extent.

Extras : 

We all know that professional photographers use big cameras. Their cameras size is big mainly because of the sensor size. And sensors of that size cannot be placed in a mobile phone. Down below is a 108MP sensor in mobile camera, not 108MP resolution mobile camera, don't get confused. It's a pretty big sensor to a mobile phone.

You got the difference, right!, if you place a very big sensor on mobile, then the mobile phone will be in the size of HULK. So, mobile phone companies tries to increase the resolution(increase in megapixel) thinking that it will compensate the clarity(sensor size) issue, but it will not compensate.