Mike Chaney's Tech Corner

Mike's Software => Qimage Ultimate => Topic started by: Martin van Gog on February 21, 2023, 11:19:11 AM



Title: Resolution file - given PPI
Post by: Martin van Gog on February 21, 2023, 11:19:11 AM
Hi,
When I transfer a file with a given resolution, in PPI, to Qimage, will in 'tab' Printers and Settings, part -> 'Processing', setting a 'Print Res', Qimage Ultimate alter the data to a (chosen)default value before sending it to the printer?


Title: Re: Resolution file - given PPI
Post by: Fred A on February 21, 2023, 11:38:22 AM
Quote
Hi,
When I transfer a file with a given resolution, in PPI, to Qimage, will in 'tab' Printers and Settings, part -> 'Processing', setting a 'Print Res', Qimage Ultimate alter the data to a (chosen)default value before sending it to the printer?
Let's start over slowly.
PPI depends on the print size and the image resolution applied to the print size. (5x7 will have a greater ppi than 8 x 10)
Now Qimage takes that data and interpolates it at the highest quality possible to the printer's desired input. (Epson = 720 ppi and Canon 600.
That file is sent to your printer using the profile and print size requested.
I will pause here as I am not sure if I understood your question.

Fred


Title: Re: Resolution file - given PPI
Post by: Martin van Gog on February 21, 2023, 11:47:33 AM
Hi Fred,
As always I make the (stupid) mistake. Of course I meant the file resolution in PPI..

with regards, Martin.


Title: Re: Resolution file - given PPI
Post by: Fred A on February 21, 2023, 12:01:55 PM
Quote
As always I make the (stupid) mistake. Of course I meant the file resolution in PPI..
Thereis no ppi with out a print size. Let's wait for Mike. Usually get into his office by 7:30 EST


Title: Re: Resolution file - given PPI
Post by: Martin van Gog on February 21, 2023, 12:02:35 PM
Hi Fred,

So if a given file has a given resolution in DPI, Qimage calculates the factor needed to get the desired resolution in PPI. "
Using: "Printer and Settings" -> "Processing" -> setting: Print Res: XXX

regards, Martin


Title: Re: Resolution file - given PPI
Post by: Fred A on February 21, 2023, 12:19:46 PM
Quote
So if a given file has a given resolution in DPI, Qimage calculates the factor needed to get the desired resolution in PPI. "
Using: "Printer and Settings" -> "Processing" -> setting: Print Res: XXX

Easy arithmetic. If your image is 3000 pixels by 3000 pixels, Qimge sees that you want a 10 x 10 print.PPI will be 300  ppi
Wait for Mike. Another 10 minutes


Title: Re: Resolution file - given PPI
Post by: admin on February 21, 2023, 12:54:16 PM
PPI makes no sense for photos: photos just have a certain number of pixels and you don't know how big you want to print them until print time.

Scans, logos, art designs, etc. could have PPI only for the purpose of telling you what size is the preferred size for that image.  You scan an 8x10 photo at 300 PPI and you get an image that is 2400x3000 pixels and it is labelled 300 PPI so that you can print that 2400x3000 pixel image at 300 PPI and get an 8x10 reproduction of the 8x10 scan.  In Qimage, you use "Original Size" if you want a copy of a scanned image at the size it was scanned (the PPI listed in the file).

Other than the above example of scanned documents, logos, and things where you want to know what size the original was, Qimage doesn't care.  It's going to take every image and interpolate it to the PPI of the printer (driver) at print time anyway: usually 720 PPI for Epsons and 600 for everything else.

Regards,
Mike