dpi convert to megapixel

tecboy

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How many megapixel is in 300dpi? The president of a nonprofit organization wants me to submit photos in 300dpi resolution. As far I know the dpi is for printing resolution.
 
None.
There are no dpi in megapixels.
Plus, you would have to state the print size.

Print size in inches times 300 PPI (not dpi) = pixels
It takes multiple dots (3 or more) to print a single pixel.
Most inkjet printers today use well over 100 dots to print a single pixel.

The width and height of the print then get multiplied together to get total pixels.

Example 8 x 10 print @ 300 PPI.
8" x 300 ppi = 2400 pixels
10" x 300 ppi = 3000 pixels
2400 px times 3000 px = 6 MP.
 
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How many megapixel is in 300dpi? The president of a nonprofit organization wants me to submit photos in 300dpi resolution. As far I know the dpi is for printing resolution.

300 DPI is a meaningless figure without the print size specified. 300 DPI would read 300 dots per inch. What you need then to calculate a number of total dots is the width and height of the print. So for example in a 300 DPI 5 x 7 inch print you'd have 300 x 5 = 1500 and 300 x 7 = 2100 and so 1500 x 2100 = 3,150,000 dots or 3.15 megadots. If you want megapixels consider that you also want PPI or pixels per inch instead of DPI.

Joe
 
Sounds like the boss wants photos that have enough information in them to provide a quality photo. As mentioned above the total file size is effected by the number of pixels per inch and how many inches of photo. When someone says they want 300dpi they are asking for a relatively high density of information. That will make for large files unless it's a small photo. If I did it right a 5"X5" photo would be almost 2 megapixels.
Understand that most non-photographers don't see any difference between DPI and PPI and many folks that understand it don't really care and use the terms interchangeably.
Software like Photoshop will give you the ability to change the pixels per inch. Most cameras have the ability to adjust the density and all scanners also will.
 
Sounds like the boss wants photos that have enough information in them to provide a quality photo.

This is not the only boss asked me for 300dpi. Previously, another boss asked me the same thing. I don't know how to explain to them to make them understand in nontechnical way.
 
Ask them how big the picture is going to be in print.
If they question that, tell them that digital images are measured in pixels not dots so you need that information.
 
The pixels per inch (ppi) only applies if a photo will be printed.
For electronic display the ppi is meaningless and has no effect on image size.

Note that when setting the print resolution in LR or Photoshop ppi is the only choice since there is no dpi for digital image files.
 
Sounds like the boss wants photos that have enough information in them to provide a quality photo.

This is not the only boss asked me for 300dpi. Previously, another boss asked me the same thing. I don't know how to explain to them to make them understand in nontechnical way.

If you know how to explain to the boss let me know please. It's one of the important knowledge in order to get promoted.
 
Schedule a meeting. Play them this.



Bosses love Powerpoint and videos.
 
I figured Management would understand it. :allteeth:
 

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