# Background

Looking to create a three-column document with images that fill entire pages, while the text has a different page layout. Both the images and the text pages should have the same total dimensions.

# Problem

The issue is that the image doesn't fill the entire page, even though the ratio of the page size (4:1) is the same as the image size (4:1), as shown here:

# Code

A fairly minimal snippet to reproduce the problem:

\definepapersize[ImpactsPageSize][
width=400mm,
height=100mm,
]

\definelayout[ImpactsPageLayout][
backspace=5mm,
cutspace=5mm,
width=390mm,
height=85mm,
topspace=5mm,
footer=0mm,
]

\setuppapersize[ImpactsPageSize]
\setuplayout[ImpactsPageLayout]

footer=empty,
number=no,
page=yes,
]

\setupexternalfigures[
location={local,default,global},
maxwidth=\makeupwidth,
width=\makeupwidth,
]

\let\oldexternalfigure\externalfigure
\def\externalfigure[#1]{%
\startTEXpage[width=\paperwidth,height=\paperheight,align=middle]
\oldexternalfigure[#1][width=\paperwidth,height=\paperheight]%
\stopTEXpage
}

\starttext
\chapter[title={One}]

\startcolumns[n=3]
\input knuth
\input knuth
\input knuth
\stopcolumns

{\externalfigure[https://i.imgur.com/q1S0abK.jpg]}
\stoptext


# Constraints

The externalfigure snippet is generated by pandoc and therefore must not be changed or altered in any way:

{\externalfigure[https://i.imgur.com/q1S0abK.jpg]}


# Question

What do I need to change to make the image fill the full page independently of the page layout of the text pages? (That is, how do I eliminate the white borders shown in the example images while maintaining the image aspect ratio?)

Your document contains a maxwidth setting for all included graphic. When you have a image which is wider than this value it is scaled down to the maximum value.

The example below shows a case where this setup is useful to keep the width of the images limited.

\useMPlibrary [dum]

\setuppapersize [A6] [A5,landscape]

\setuparranging[2SIDE]

\showframe [text] [text]

\starttext

\externalfigure [a] [width=1.1\makeupwidth]

\page

\setupexternalfigures [maxwidth=\makeupwidth]

\externalfigure [b] [width=1.1\makeupwidth]

\stoptext


The wiki's layout page shows various ways that the makeupwidth can be calculated. Specifically:

\makeupwidth is normally same as \textwidth, but it can be different, for example in columns.