Image resolution is one of the most simple yet most confused topics in photography. Lot of mis-information is there online which makes things worse.
First things first what exactly is Image Resolution?
Simply put Resolution of an image is the total number of pixels that image contains.
No. of pixels in width X No. of pixels in height = Total no. of pixels
As an example:
7360 pixels X 4912 pixels = 36152320 pixels = 36 Million Pixels
This is a typical example of a 36 Megapixel Image.
In other words, a resolution of any image determines how much details have been captured in the image.
Relevance of PPI
One myth very popular on internet is that the best and optimum resolution of an image for viewing it on internet is 72PPI. This is actually the biggest lie being spread on internet. Display screens do not consider Pixels Per Inch (PPI) for displaying images. They consider total number of pixels.
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