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I have 285 Tiff files that make up the 1:10000 OS map of Norhtern Ireland. I am having problems running QGIS when I try to load all 285 tiff files in for base maps (I think the memory on computer is problem here) My thinking was if I create a geodatabase this will speed up accesssing these base maps. I also have with each tiff file a corresponding AUX , RRD, TFW file. There is a historical DBF file that appears to index each Tiff file with max and min x.y coordinates. I beleive this was used for ARC 3?? Is there any easy way to get this DBF file into a spatial database to allow me to access the Tiff files quicker? I tried pyrimids on the Tiffs but they are not 'pyrimid-able'. I also tried to create a geodatabase using spatialite but becasue the Tiffs are not geo-referenced (this info sits outside the Tiff file on the TFW file) it would not allow me to load them into my DB.

Any assistance would be greatly appreciated

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I would suggest to build a virtual raster with gdalbuildvrt or Raster->Others->Create Virtual Raster inside QGIS.

Most probaly you have to apply a CRS to your tif-files first with gdalwarp or Raster->Projection->Apply projection.

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Also, after you've created the VRT, you should run gdalinfo -approx_stats on that file. That gave a great improvement in rendering for me – Micha Dec 13 '12 at 8:28

I recommend you run gdal_translate.exe to convert your tiffs into geotiffs. Most importantly, you can also assign the coordinate system or CRS during the conversion. The tfw information and projection info will then be embedded inside each geotiff. The Spatialite, Raster tools may work better once you have valid geotiffs.

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