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Hi,
I've been designing for many years and have just noticed that in the updated version of Photoshop that I have (cc 2017) the settings are all now for ppi not dpi.
Is there a way I can change that? I prefer to use dpi.
Thanks in advance!
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They have been ppi for as long as I can remember. PPI (pixels per inch) is for screen and DPI (dots per inch) is for out to an ink jet printer.
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And when talking about halftone printing (offset or gravure for example) there’s lpi …
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Silkrooster is entirely correct. Pixels per inch means one thing, dots per inch means something else. In your printer settings you'll see DPI. In Photoshop it's PPI.
Splitting hairs maybe, but it pays to keep the concepts straight. PPI is probably the most misunderstood acronym in the entire history of raster image processing - until you look at what it actually means.
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The input pixels are not always equal to printer dots. It all depends on the printer.
Common inkjets like the Epson Stylus Photo 5760 x 1440 dpi specs require 360 ppi inputs since the "dots" are dithered. 1440/4 = the recommended 360.
And I think Commercial Presses go by line-screen 150 lpi (artbook quality) x 2 = requires 300 ppi.
That was a couple of years ago, the press technology must be way different now.
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If a press is printing haftone dots, which is still the most common screening for offset, the imagesetters or platemakers draw the halftone dots (lines per inch) with smaller printer dots (dots per inch). The haftone screen creates the illusion of continuous tone by varying the size of the haftone dot. The output device has to be capable of a high enough resolution to accurately draw the various sized haftone dots—a 150lpi halftone screen would typically need a 2400 dpi output device.
Inkjet printers use a stochastic screen to create the continuous tone illusion. In that case the screen dots are all the same size and the tones are created by varying the spacing between the dots. Offset presses can also print stochastic screens, but they are usually more difficult to print.
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The simple answer is "no" you can't change it. As previously mentioned, images have pixels, not dots.
For traditional printing the general rule for PPI is 1.5 time or 2 times the LPI. More resolution that is required just slows down the output process. I've always used 1.5 x the LPI; so for 150 LPI, I had 225 ppi.
That's slight more than a laser printer needs, but close enough. That way I'm covered for either print method.
It's important to note that if you pre-size your images to the 1.5 method, you can always reduce but not enlarge.
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mbdesigner schrieb
… that in the updated version of Photoshop that I have (cc 2017) the settings are all now for ppi not dpi …
Can you show us a screenshot, please?
There is no version (that I know) in which you can set dpi in file new dialog.
eg PS 6.0
or PS CS2
or now in PS CC
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PS 1.0