Image resolution not recognized by Adobe Photoshop

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abaabheejaa

Image resolution not recognized by Adobe Photoshop

Post by abaabheejaa »

Hello,

I am new to Imagemagick.

I used the following in succession to get first, a 600dpi image, and then resize it to 3.25 " at 1200 dpi (3900 pixels)

convert -depth 8 -compress LZW -density 600 input.ps dpi-600.tif
convert -depth 8 -resize 3900 dpi-600.tif dpi-1200.tif

However, when I read the image into photoshop, it is detected as a 72 dpi image of 54.17 inches (3900 pixels)

So, photoshop reads the pixels right, but not the resolution.

Does anyone know how to resolve this issue?

Thanks,

-Ashu
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fmw42
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Re: Image resolution not recognized by Adobe Photoshop

Post by fmw42 »

change the order - current syntax is:

convert <infile> options <outfile>


see http://www.imagemagick.org/Usage/basics/#cmdline
abaabheejaa

Re: Image resolution not recognized by Adobe Photoshop

Post by abaabheejaa »

Interesting. When I change the syntax to as recommended in the second post, the density option does not seem to work at all. All I get is screen resolution. So for me, the following works at least to get the right resolution (600 dpi) :

convert -density 600 options <infile.ps> <outfile.tif>

But the following does not:

convert <infile.ps> -density 600 <outfile.tif>
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fmw42
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Re: Image resolution not recognized by Adobe Photoshop

Post by fmw42 »

The density needs to be specified before the input .ps image as you are telling it what the starting resolution is. But if you want to change it for the tiff and for all the other options, they need to be put after the input image.
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anthony
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Re: Image resolution not recognized by Adobe Photoshop

Post by anthony »

Actually that should be

Code: Select all

   convert {read settings} {input_image} {operators and settings} {output}
so the command should be

Code: Select all

   convert -density 600  infile.ps  outfile.tif
however for a higher quality result it is recommended you super-sample the input at a higher density, say 4 times... For example...

Code: Select all

   convert -density 2400  infile.ps  -resample 600  -depth 8 -compress LZW outfile.tif
Back to your original problem however. Photoshop does NOT read the density of an image unless, no photoshop profile is present. and then it is doubtful.
I would not recommend TIFF format as it is so ill-defined.
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/
abaabheejaa

Re: Image resolution not recognized by Adobe Photoshop

Post by abaabheejaa »

Dear All,

Thank you for the replies.

If not tiff, then what image format does one typically use to submit to, for example, scientific journals? If it is .eps, how does one go about converting a .ps to a .eps?

Thank you again,

Ashu
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anthony
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Re: Image resolution not recognized by Adobe Photoshop

Post by anthony »

and .eps is just a special form of .ps file. One that is a single page, and contains a bounding box defining the drawing limits.

ghostscript has a ps2eps program to generate the bounding box information.
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/
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