USGS makes 500dpi DRGs but doesn't seem to offer them for download anywhere. There are several vendors that I can find offering seamless DRGs but only in 250dpi. Where can I find 500dpi seamless DRGs for Oahu?

GeoPDFs will not work-- I have already tried importing them to Photoshop, exporting high res TIFFs, and georeferencing those, but I really need the edges to match perfectly.

  • If you have the data in GeoPDF format, GDAL supports it (gdal.org/frmt_pdf.html) and you can convert to GeoTIFF retaining the georeferencing metadata. – bosth Sep 29 '15 at 19:29
  • I think it's more time/cost effective to pay a few bucks for existing 500 DPI pdfs vs spending weeks or months learning how to compile and then use GDAL. I would still then need to figure out how to clip each DRG to remove everything outside the neatlines – KMWPJPL Sep 29 '15 at 20:58
  • I doubt you'd need to compile GDAL and the command you'd need is dead simple. – bosth Sep 29 '15 at 21:02
  • OK, can you please post the command? I'm sorry but I can't find it anywhere. There are plenty of references on various forums to using GDAL to do the conversion but no one posts how to actually do it. – KMWPJPL Sep 30 '15 at 18:34
  • I followed the instructions here and it seems to work, I just need to figure out how to crop out the collar area nationalmap.gov/ustopo/documents/ustopo2gtif_current.pdf – KMWPJPL Sep 30 '15 at 19:09

To convert a GeoPDF image to a GroTIFF with GDAL, use the following command: gdal_translate input.pdf output.tif.

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