# Grdview

**URL:** <https://forum.generic-mapping-tools.org/t/grdview/4325>\
**Category:** Q&A\
**Tags:** gmt, cpt\
**Created:** [October 7, 2023, 4:25pm UTC](https://forum.generic-mapping-tools.org/t/grdview/4325 "2023-10-07T16:25:16Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![bag](https://avatars.discourse-cdn.com/v4/letter/b/8e8cbc/32.png) [@bag](https://forum.generic-mapping-tools.org/u/bag)\
**Post date:** [October 7, 2023, 4:25pm UTC](https://forum.generic-mapping-tools.org/t/grdview/4325/1 "2023-10-07T16:25:16Z")

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Hi,  
Please, I want a mesh plot showing the bathymetry of my region of interest. When i run the script below i get black mesh plot instead of a rainbow or geo mesh. What am I doing wrong? Pardon my ignorance please.

gmt begin 3D png

gmt grdcontour my\_gog.nc -Wthinnest,dimgray -C1000 -Gd3c -A1000+f4+o -p130/30

gmt coast -p -B4 -BNESW -Gdimgray -TdjBR+o0.3c+w3c+l

gmt grdview my\_gog.nc -I+a15+ne0.75 -R-13.9/14/-19.9/6.4/ -JZ4i -p130/30 -Cgeo.cpt   
-N-6916+glightgray -Qsm -BnSwEZ+b -B2000 -Bz2000+l"Bathymetry and topography (m)" -Y3i

gmt end

 ![nnn](https://canada1.discourse-cdn.com/flex047/uploads/gmt/original/2X/f/f7b673a74b548c9ad44f54d603ad979168070f68.jpeg)

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<div class="post-metadata">

**Author:** ![pwessel](https://yyz1.discourse-cdn.com/flex047/user_avatar/forum.generic-mapping-tools.org/pwessel/32/30_2.png) [@pwessel](https://forum.generic-mapping-tools.org/u/pwessel)\
**Post date:** [October 7, 2023, 5:44pm UTC](https://forum.generic-mapping-tools.org/t/grdview/4325/2 "2023-10-07T17:44:25Z")

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Assuming your grid is large (large number of rows and columns) you are mostly seing black mesh lines. Try -Qi100 first, then -Qi300 perhaps. Or see -T.