Does image quality depends only on PPI?

[aikorush]

I am not 100% sure how it works and if its called DPI or PPI but I will use PPI here.

I noticed that my Galaxy S6 has like um 500+ PPI? And i heard more PPI means the crisper

Recently I ordered a 28 inch 4K monitor, and i used an online PPI calculator and its around 157 PPI compared to the S6 which is around 500 something

So does this mean that the S6 will look better than the 28 inch 4K monitor I am getting or something?

 

[Seyed22Shaheen]

Your Monitor will have 8,847,360 pixels spread across 28" display when your S6 will have 3,686,400 pixels spread across ~6" But your monitor is viewed from desk while your phone is viewed from your hand near to your Eyes. PPI is more complex than comparing which has more numbers, and it is said anything beyond 400 PPI does not even make a difference to our eyes...

 

[caqde]

Some other things to keep in mind besides the crispness of the image. Color accuracy, Color quantity, Contrast, refresh rate, and viewing angles. You can have as many pixels as you want but if you have horrible color accuracy and you're only able to view it correctly from a few select angles without color distortion then regardless of the crisp image you might be able to get your image will be bad.

Also as Seyed pointed out the viewing distance also plays a large part in this. The closer you are to your display the large the PPI you will want as our eyes will naturally be able to decipher the difference between individual pixels of smaller sizes. Because most people view their phone from maybe a foot or so away from their eyes more PPI are required to create an image we would view as being crisp and sharp. Whereas a TV or monitor will need far less for the same effect due to the much larger distance between the viewer and the display especially TV's.

 

[rgd1101]

MERGED QUESTION
Question from aikorush : "Does image quality depends only on PPI?"

I recently posted this but I wasnt sure where i posted it so i am reposting this again

I am not 100% sure how it works and if its called DPI or PPI but I will use PPI here.

I noticed that my Galaxy S6 has like um 500+ PPI? And i heard more PPI means the crisper

Recently I ordered a 28 inch 4K monitor, and i used an online PPI calculator and its around 157 PPI compared to the S6 which is around 500 something

So does this mean that the S6 will look better than the 28 inch 4K monitor I am getting or something?

DPI an diagonal are only part of the equation. You also have to take into account the distance from which you will be viewing your device. The closer you are, pixels get bigger, so it is natural for small devices which are being looked from up close to have high pixel density. It is highly unlikely that you will watch your 28 inch 4K monitor from the same distance as you watch your smartphone, for example.

Here, this calculator might help a bit:

https/stari.co/tv-monitor-viewing-distance-calculator

1. size of screen example:
That's why Sharp made this head-turning new 4K IGZO screen with over 1,000 pixels per inch. I don't know the exact size of the display, but to hit that ppi at 3840 x 2160 it'd need to be smaller than 4.4 inches across.
2. resolution
3. distance

size/resolution = PPI (or 1/PPI) I dont remember.

inch of the screen is smaller, further you are from screen, so 40 PI will be a good for masive TV, not for phone. For phone 400 PPI is great, but as with example above you end up with incredible resolution on very small screen.


DPI vs PPI = 1 pixel is made from multiple colors, in rgb its 3 dots per pixel.
Every pixel output is made up of different coloured inks (usually 4-6 colours, although many printers use more now).