I downloaded a GeoTIFF DEM from EarthExplorer and loaded it onto QGIS. This GeoTIFF is of the state of Florida. I have a shapefile (polygon) of the state and want to overlap it with the raster file so people can see where Florida's outline rest on the DEM. However, when I put two of them into QGIS the Florida shapefile is so much larger than the raster image (it covers up the entire image).

Both of these files have the same coordinate system so I'm a little confused. Is there any way I can somehow shrink the polygon file to fit into the raster image to show the state?

Here is an image:

enter image description here

  • Welcome to GIS SE. As a new user, please take the Tour. You'd have to make raster pixels infinitely small to follow an angled line (which would mean the image would be infinitely large). Vector GIS exists so that you don't need to make that choice. You could certainly apply a negative buffer to the vector layer, but doing so would corrupt it, topologically, so it no longer represents what you claim it does. Traditionally, the way to present this is to place the vector on top of the raster (potentially with transparency). – Vince Jun 4 '18 at 2:30
  • Your question is very unclear. Can you edit it and show a picture of what you mean and also include gdalinfo report (or the QGIS layer metadata as text) for the raster DEM and ogrinfo report (or the QGIS layer metadata as text) for the shapefile. If you have changed the projection/CRS of either, include that information. – user2856 Jun 4 '18 at 3:00
  • Are you sure you downloaded the whole state's DEM? Many of the DEM products are served as tiles. As Luke said, a picture would be very helpful. – Jon Jun 4 '18 at 3:22
  • Hi all, I just added a photo of my issue. I essentially want my polygon to fit in with my image, Both are on the same coordinate system and projection. – Leo Ohyama Jun 4 '18 at 3:38
  • 2
    What you show in your screenshot is correct, I think I found the DEM you downloaded - i.stack.imgur.com/xPUp2.png. You have a DEM tile that covers only a small part of Florida, it's a section of a larger DEM. If you want a DEM that covers all of Florida, you need to download more tiles and mosaic them. – user2856 Jun 4 '18 at 4:02

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