fuzzy images - why is this happening?!?

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rocking

I have been using Scribus to produce a club newsletter (10 issues per year) since June 2021 which means I am working on my 40th issue.  I generate a 300 dpi pdf for printing and also generate a 100dpi pdf for online viewing.

I am on Linux (Ubuntu).  I use images (mostly jpg) as they are sent to me as most do not need editing. If one does, for something like removing keystoning, then I will use gimp.

There is a weird thing that sometimes happens with images and I cannot explain it, and it is happening again with a couple of images in the next issue and I am tearing my hair out over it (please help me not go bald!)

I have an image that gwenview reports is 1920x120, 2.3 MP and X and Y resolution is 250.  However, in an image frame that is 263.5 pt width, the image is blocky and blurry. The image actually looks better in the generated pdf, even the 100 dpi, but it is still pixelated compared to the image when viewed in gwenview.

Images attached show the signature (at bottom left of image):
-- on screen view, at 200%.
screen-view-at-200-pct.png
-- pdf generated at 100 dpi, at 100%
pdf-100dpi-at-100-pct.png
-- image, from gwenview, at 100%.
gwenview-at-100-pct.png

I hope this is understandable.

rocking

I should also note that I tried removing the exif data, in case that was messing things up, but it made no difference.  The exif data is shown below.

Quote$ exiv2 -PE Bathurst\ Power\ and\ Paper\ S-3\ 1961.JPG
Exif.Image.XResolution                      Rational    1  250
Exif.Image.YResolution                      Rational    1  250
Exif.Image.ResolutionUnit                    Short      1  cm
Exif.Image.Software                          Ascii      49  Adobe Photoshop Lightroom Classic 10.1 (Windows)
Exif.Image.DateTime                          Ascii      20  2021:01:10 17:26:29
Exif.Image.ExifTag                          Long        1  172
Exif.Photo.ExifVersion                      Undefined  4  2.31
Exif.Photo.OffsetTime                        Ascii      7  -05:00
Exif.Photo.ColorSpace                        Short      1  sRGB

a.l.e

If you right click (well, trigger the context menu...) on the image, and go into the "Preview Settings", what is the currently selected value?

If it's "Low Resolution", you now know what is happening...

rocking

#3
Quote from: a.l.e on May 05, 2025, 07:14:58 PMIf you right click (well, trigger the context menu...) on the image, and go into the "Preview Settings", what is the currently selected value?

If it's "Low Resolution", you now know what is happening...

I did not realize that menu was there, obviously have never had to use it before.

The selected value was "Normal resolution".  I changed it to High and now it looks good.  It's a bit of a pain to do this for every image.

Thank you to a.l.e. for bringing this to my attention.

Nermander

The setting only affects the display when working on the document. PDF export will use the full resolution no matter this preview setting.

And in Document setup, under Item tools and Images you can set the default (but I suspect it only applies to newly created image frames).

I am not sure if there is an easy way to change for all already created image frames, but using the Outline window it is a lot easier than to do it on each page. Maybe it is possible to select multiple image frames and change the setting for all of them at the same time...

Yes, that seemed to work, I created two image frames, selected them both and changing the Preview setting then changed it for both.

AdmFubar

Quote from: rocking on May 06, 2025, 04:02:24 AMThe selected value was "Normal resolution".  I changed it to High and now it looks good.  It's a bit of a pain to do this for every image.


There is a per document setting for image resolution to display. It is in the view menu, It is set to Normal usually. Look for it in the main toolbar, it is usually the last section and has monitor with some color block displayed in it (color management), and an eye icon (print preview), and an edit in preview mode, (looks like an old ink pen) and another drop down menu for previewing your document in various color vision deficient versions)
Using Scribus 1.5.8 & 1.6.3, 1.7.0 openSUSE 15.5
Advanced hobbyist