<div dir="ltr"><div>Hi Andrew,</div><div><br></div><div>It's odd that you are getting inconsistent results. Do you see the same thing if you write to a PS or PDF file? I don't know what's going on, but it looks like a bit of overzealous anti-aliasing. There's a resource to control whether antialiasing is applied or not:</div><div><br></div><div><a href="https://www.ncl.ucar.edu/Document/Graphics/Resources/wk.shtml">https://www.ncl.ucar.edu/Document/Graphics/Resources/wk.shtml</a></div><div><br></div><div>It's on by default and generally yields better results, but you might experiment with it.</div><div><br></div><div>Wish I had a better answer.</div><div>Rick</div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Jun 22, 2021 at 8:45 AM Andrew Kren - NOAA Federal via ncl-talk <<a href="mailto:ncl-talk@mailman.ucar.edu">ncl-talk@mailman.ucar.edu</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">Hi there,<div><br></div><div>I am plotting radar data and overlaying highways onto the map. I first plot the radar analysis, then overlay the highway information by reading/plotting the shapefile.</div><div><br></div><div>At times, when I view the PNGs, the highways show up as blotched out (lack of detail and pixelated; see attached image). At other times, the highways show up very clear and darker as expected. Is there a reason for this? Below shows a snippet of my code that produces the radar plot and the highway overlay.</div><div><br></div><div> plot = gsn_csm_contour_map(wks,radar,res)<br><br> ; add highway polylines to the map from shapefile<br> plres = True<br> plres@gsLineColor = "grey48"<br> plres@gsLineThicknessF = 0.2<br> id = gsn_add_shapefile_polylines(wks,plot,SHAPE_DIR+"roadtrl020.shp",plres) <br></div><div><br></div><div>Thanks,<br clear="all"><div><br></div>-- <br><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><pre cols="72" style="white-space:pre-wrap;color:rgb(34,34,34);font-family:"arial black",sans-serif"><span style="font-family:arial,helvetica,sans-serif">Andrew Kren
Meteorologist
NOAA's National Weather Service
Raleigh Forecast Office
1005 Capability Drive, Suite 300
Raleigh, North Carolina 27606
voice: 919-326-1035
mailto: <a href="mailto:andrew.kren@noaa.gov" target="_blank">andrew.kren@noaa.gov</a></span><span style="font-family:arial,helvetica,sans-serif">
</span><a href="http://www.weather.gov/rah" style="color:rgb(17,85,204)" target="_blank"><span style="font-family:arial,helvetica,sans-serif">http://www.weather.gov/rah</span></a></pre></div><div dir="ltr"><img src="https://www.aoml.noaa.gov/pix/AOML/50th01.png" width="420" height="65"><span style="color:rgb(0,0,0);font-family:Helvetica;font-size:12px"><br></span></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div>
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