Mike Chaney's Tech Corner

Hi There,

I am using Epson stylus Pro 7800 printing on 17 and 24 inches roll paper.

Noticed the [output resolution for printers] limits to Max-360 PPI.
Attached please find the example of the red area in my screenshot.

But my Epson Stylus Pro 7800 : Maximum Resolution = 2880 x 1440 dpi from Epson.com.
https://files.support.epson.com/htmldocs/pro78_/pro78_rf/infor_1.htm

I have another Epson WF-7710: Maximum Print Resolution: 4800 x 2400 dpi.
Which is limit to Max-600 PPI.

Is there anything wrong with my setup or settings that I can change to use the max resolution?


Thank you!

You are conflating PPI and DPI.  PPI is the resolution of the image in pixels.  DPI is how many dots of ink the printer can lay down. It takes many dots of different color ink to make one image pixel.  There's a lot of info on this in this forum as well as elsewhere on line written by people smarter than I am.

Right.  That "Max 360 PPI" is what the printer driver is reporting to Windows as the requested input resolution (resolution of the images being printed).  The printer will still print at its maximum resolution as long as you have it set to highest quality in the driver and you select a good photo paper.  Most Epson drivers default to 360 PPI (which is what the driver requests for the image resolution) especially when using larger paper sizes, but there's a setting in the driver called "Finest Details" that you can check and that will increase this "native driver PPI" from 360 to 720.  The reason for the difference is that it takes a lot of printer dots (DPI) to resolve the color detail in one pixel (PPI).

Regards,
Mike

Thank you so much for the explanation.

Epson stylus pro 7800 has 8 colours.
Did my math 2880/8 = 360.

Wich looks awesome on any large print.

You have a wonderful day!