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While opening in a browser a 2018 Geospatial PDF from the USGS, I noticed that different PDF browsers open the same file differently. I'm looking for a clue as to why they are different.

Compare

When comparing the same Geospatial PDF in four browsers on macOS Mojave (macOS 10.14.3 (18D42)) —

  • Chrome & Opera show only the most basic vector layers (contours, roads, etc)
  • Safari & Firefox shows contours, roads, etc, but also shows the Orthoimage base layer. The Preview app on macOS Mojave also behaves like Safari and shows the Orthoimage.

Issue

I am not certain which browser is right. These are the scenarios that could be happening:

  1. Chrome and Opera use the same PDF renderer; read the Geospatial PDF and decide to not show the Orthoimage layer, or
  2. Firefox and Safari use strong rendering standards, and the Geospatial PDF does not give that proper directive, or
  3. The issue is related to 2018 USGS Geospatial PDF produces `ERROR 1: insufficient arguments for Marked Content`, or
  4. Your guess is good as mine. BTW, the USGS PDFs are excellent and my hats off to them for refreshing the US Topo products.

Steps to Reproduce

For example, if I obtain this 2018 Geospatial PDF from the NationalMap.gov

 wget https://prd-tnm.s3.amazonaws.com/StagedProducts/Maps/USTopo/PDF/CA/CA_Descanso_20180904_TM_geo.pdf

And I open it on the browsers I have on macOS (Chrome, Safari, Opera, FireFox), I get the rendering of each in the image below. Safari & macOS Preview & Firefox both show the Orthoimage layer.

browsers


Edit

I have found that a National Park Service Geospatial PDF for Joshua Tree has a similar issue. This again leads me to believe its how the PDF renderer for these browsers behaves differently.

Steps to reproduce Joshua Tree, where the Shaded Relief layer does not show in macOS Preview.

wget  https://www.nps.gov/carto/hfc/carto/media/JOTRmap1.pdf

NPS Geospatial PDF that exhibits the same problem

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