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I designed a big front-cover for a magazine in Photoshop. I put the PNG into an ODT-Open-Office-File and then save it as a PDF. When I view it with Adobe Reader ...

enter image description here

It seems to be a display-problem!? I want that the graphic is looking good at every percentage of view. Thanks for help, dudes!

  • 1
    Is there any reason you're exporting a PNG, placing that in OpenOffice and exporting a PDF from there? Seems a bit of a strange workflow. – Cai May 30 '16 at 10:17
  • Hey, Cai. My articles are all saved separately as PDFs. In the end I will put them all together. Saving the cover that way, too, yeah. I'm not sure if that is part of the problem!? – Lazereye May 30 '16 at 10:33
  • You can save it as a photoshop PDF, if I remember correctly office programs tend to put funny compression on things. – Jenna May 30 '16 at 11:39
  • Hey, Jenna! I tried it with photoshop, too. It's even more worse, I think. Need to choose a 180% view ... then the graphic looks ok. It's crazy. It seems to be TOO high-quality!? – Lazereye May 30 '16 at 12:06
  • @Lazereye is this for print or a digital magazine? – Cai May 30 '16 at 12:10
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If your image looks as it should when you zoom in there is nothing wrong with your image. OpenOffice may be resampling or compressing your image, but if it looks as it should at a higher zoom level then I assume that's not the problem. The problem is how Adobe Reader is rendering your image.

It's physically impossible for any image to render perfectly at any scale. Your image is made up of pixels, if you scale your image by any non-integer amount those pixels don't align with the new scale and you get those jagged edges (aliasing), which are especially noticeable on thin lines.

At a guess, the 140% zoom in Reader is probably showing your image at 100% (or some integer scale) in regards to the images actual pixel size and your display. This may be due to you scaling the image in OpenOffice or just due to Reader basing its scale on the physical dimensions of the PDF not the pixel dimensions of the image inside that PDF.

If this is destined for print you shouldn't need to worry about it, the issue is a screen display problem that won't translate to a printer.

One thing to check is Readers rending preferences to see if anything there is affecting the quality. (Preferences > Page Display > Rendering). I don't have Reader installed here so I'm not sure but I know there are font rendering options there.

Regarding your workflow, you can export a PDF directly from Photoshop so there's no need to use OpenOffice for that. A more usual workflow would be exporting a PDF or high res TIFF from Photoshop and using InDesign or some other page layout software to put everything together.

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    Aww, Cai! Thanks for this amazing answer! You opened my eyes. I just made the picture a little bit smaller and now it looks good at 100% - 130%! Brilliant! Thanks! :) – Lazereye May 30 '16 at 14:17
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Short answer: Never trust a .pdf viewer.

Long answer: .pdf viewers are fallible. The PDF standard is very broad and has many applications. It displays files on-screen, and also creates print-ready files. Because of this broad application of the file type, there is no single .pdf viewer that can render all kinds of files acceptably all of the time.

You could try to save the image with different settings, have a source image of different sizes, or other solutions. You will always find a viewer and / or OS that renders it incorrectly. That's life.

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    Thanks, mate! Problem is: It will be an eZine ... so many people will watch it with the Adobe Reader, I think. But I rezised the picture ... and now it looks pretty good at 100%-140%!!! Thanks again! – Lazereye May 30 '16 at 14:19
  • @Lazereye actually not that much as you can think. First: Adobe Reader is missing for many platforms. Even when it exists, I generally — when asked by someone — don't recommend it, as it leaves some weird processes on startup, plus doesn't support fb2, djvu, etc, as most readers, like Evince, Okular, usually do. Second: it is rarely used on mobile platforms — in particular for mentioned reasons, and eZines very often being read just on mobiles, like en route, waiting for queue, etc. – Hi-Angel May 31 '16 at 4:49
  • Thx for the informations. To be honest ... I haven't got a mobile-phone ... so I think everyone is weird as me. Do you think the graphic will look good on the mobile-devices? – Lazereye May 31 '16 at 5:19
  • @Lazereye idk, but I doubt it would look somehow bad. It's just that I don't think most PDF files are tested there, however, I, as one reading many of them (en route to work), didn't ever notice problems. UPD: though I should mention that I rather reading books and thesises than e-journals. – Hi-Angel May 31 '16 at 5:30
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This is a bit of a guess, but it's possible that the 140% ratio relates to the difference between 96dpi (which I think is the default DPI of OpenOffice) and 72dpi (the default DPI of Photoshop). Which is a ratio of 1.333.

If you haven't already, try changing the DPI of your original image to 96. Don't resample it, just change its resolution.

  1. Go to Image->Image Size
  2. Turn off "Resample Image"
  3. Change Resolution from 72 to 96
  4. Click OK

Save the image and try importing it to OpenOffice again. See if that works any better.

  • Assuming it's being shown at exactly the same size and your not resampling then the PPI value in itself shouldn't make any difference. (If you were to resample and change the pixel dimensions, or if you're scaling it based on the PPI then obviously it would) – Cai May 30 '16 at 18:25
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I second that disparagement of PDF viewers and PDF because I have had numerous problems over the years.

  • I created a simple graphic in inkscape that rendered differently 4 ways on 4 viewers.

  • Badly formed (per Adobe) PDF files can display ok on 3rd party viewers but not in acroread.

  • A PDF file can be viewable fine but its text not selectable, e.g., if created by xelatex.

  • One PDF file printed differently on 2 different HP laser printers.

The PDF language is big enough that creators can make errors and renderers can ignore rare features.

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