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Background imagery

Background imagery gives the map context — runways, buildings, terrain — that the analysis engine never reads but that you rely on for siting decisions. In Siter, raster imagery comes only from the built-in base-map switcher; layers in the layer panel are always vector. When the built-in imagery is insufficient, the workaround is a vector reference layer, not a custom raster.

Learning objectives

By the end of this lesson you should be able to:

  • Switch the project's base map and recognize what changes
  • Distinguish the built-in raster base map from vector reference layers
  • Recognize when built-in imagery is insufficient and what your options are

Built-in base maps​

Siter ships with several base map options. The choice is purely visual — none of them affect analysis, and you can switch the active base map at any time without re-running anything. The base map sits below every layer in the panel; switching it does not affect any QD-visible or background layers stacked above.

Siter does not import raster imagery as a layer​

A common expectation from other GIS tools is that you can drop a GeoTIFF or PNG aerial onto the map as a custom imagery layer. Siter does not support that. All layers in Siter are vector — geometry, attributes, optionally explosives. There is no "imagery layer" type.

When the built-in base map does not give you enough context for a siting decision, the practical workarounds are:

  • CAD polylines from a .dwg — engineering site plans authored in AutoCAD usually contain the building footprints, road centerlines, and other features you would want as imagery. Import the relevant polylines as a background layer; see AutoCAD.
  • Shapefile or GeoJSON reference data — installation GIS departments typically have parcel boundaries, transportation networks, and similar content as shapefiles. Import as a background layer; see Shapefile import and GeoJSON.

In every case, the result lands as a vector background layer — not as a raster.

When the base map is enough​

For most siting work, the built-in base map plus a few targeted background layers (parcel boundaries, road centerlines) is the complete picture. Reach for custom reference content only when you can name a specific deficiency the built-in imagery has — outdated, low-resolution for the site, missing a feature you need to site against, or compliance constraints on imagery source.

Try it​

In any project, cycle through the available base maps and observe what changes (and what doesn't) on the map:

  1. Feature shapes and labels stay exactly where they were
  2. Arcs and analysis results are unchanged
  3. Only the map underneath changes

This is what makes the base map safe to switch freely — it is purely cosmetic.

  • Adding layers — background-flavored layers carry vector reference content
  • Organizing layers — reference layers belong near the bottom of the order
  • AutoCAD — pulling polylines from .dwg as background reference
  • Shapefile import — vector reference content from a GIS source
  • QGIS — pre-processing vector reference data before import