The get around I have used is to make a custom atlas layout
 
Here I put my paper size, scale and critically the origin of the area I wish to extract.
e.g.
  scale 1 1250
 
  #NAV PANE     
  #--------     
  nav-factor  30   
  nav-size  1  1 
     
  #PAGE LAYOUT   Custom paper size  
  #-----------       
  page-setup  35  45  \   
              34  43  \   
              1.0  1.0  cm  
              # paper width, height, page width height, margins left, top, overlap
     
  overlap     0  cm        # default 1 cm
     
  size        32  36  cm       # 8cm = 100m
 
own-pages 1
title-pages off
#exclude-pages on 1,5,6,11,15
 
   cs OSGB:SO
   origin 17540 16300 200 m  # change to top left of area
   origin-label 1 1
 
All I then need to do is save the required single page of the multipage pdf.
 
It would be useful to know how to turn off the scale bar , nav grid and title.
 
John S
 
 
 
Sent: Monday, July 2, 2018 1:43 PM
Subject: Re: [Therion] Page Size
 
 
2. 7. 2018 v 8:52, Markus Boldt via Therion <therion@speleo.sk>:
 
I have thought there could/must be a possibility directly in Therion. 
 
The size of map is calculated from scale. So if you change the scale of map, the you’ll change the size of final output. A bit calculation.
 
Martin S.
 


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