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I use an M1 Mac and have set the screen at 218 ppi in Photoshop, which is apparently correct for its screen.
What does a screen do to an image that is set to print at 300dpi, does it delete a certain amount of information to show the image correctly?
I have set the print resolution for new docsuments at 300 ppi...
Is that the same as printing at 300 Dpi?
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Your screen resolution only affects how the image is displayed on screen, not how it prints. This is in reference to the display control panel on windows, and the finder preference on mac.
There are settings that affect both like effect >> Document Raster Effects Setting. Illustrator for the most part is a vector program and vector items print at max resolution of the printer. You can place bitmapped images and create bitmapped effects like gaussian blur, those print at the resolution they are at.
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The screen resolution is used to calculate how big the document will appear when using View > Print size. The aim is to enter the value so that the rulers at Print Size look physically correct (20cm = 20 cm on screen). There is also an Actual Size which picks up the screen resolution automatically, if the screen is passing it through the operating system correctly.
As for ppi versus dpi. Images are made of pixels, so ppi is the correct term for printing - literally how many pixels will be printed in 1 inch.
dpi is often interchanged for ppi, but is incorrect to do so, as it describes the dots that will make up each pixel. So set ppi to the value you require for printing and that is it.
You will see some inkjet printer documentation saying the printer can print at 2800 dpi. That is correct, but they cannot print at 2800 ppi (remember dpi is dots not image pixels). A max of 720ppi on those printers is common sometimes 300 or 360ppi
Dave
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Thanks for the help
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If I create a jpeg at 300dpi in photoshop, how does that relate to 2880 x 1440 dpi printing?
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You create a document at a ppi value, so in your example 300ppi (not dpi).
The printer settings, in the printer driver, may enable you to choose a printer quality and set the dpi to 2880 x 1440dpi. That sets how many printer dots will be laid down on the page. So in every square inch you will have 300 x 300 pixels on the paper. Each of those pixels will be made of 9.6 x 4.8 printed dots so making up 2880 x 1440 dpi. It's actually not quite that simple due to the way inkjets lay down their pattern of ink dots but the principle is there.
Dave
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2880 x 1440 is what the printer actually puts on the paper, either by scattering small drops of ink or clustering toner to make halftone dots. The printer driver takes the 300 ppi information, and processes it as needed for the printer to output it at the desired size.
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First, the most accurate way to view anything (Photoshop, Lightroom Classic etc) is at 100% (or 1:1). Zooming out subsamples the preview and can produce a less accurate preview of the image data.
As for DPI vs PPI etc. There is zero difference in a document that is 1000x1000 pixels (as an example) at 72 dpi (PPI) or 720 dpi (PPI) or any such value. All are 1000x1000 pixels and the dpi/ppi is simply a metadata tag.
This very, very old primer on resolution still seems necessary to post, this may help in understanding the differences:
http://digitaldog.net/files/Resolution.pdf