Plotting after blockmean preprocess with grdview

Hello all,
I’ve been plotting some data that was preprocessed with blockmean and after plotting with grdview the images appear with a grid of white faint lines. Any idea of why this happens and how can i fix it?
João Rocha

Do you have -B[…]g[…] somewhere?
-Ba adds automatic annotations
-Ba10f add annotations every 10 units as well as automatic ticks
… and -Bafg also add gridlines

If this is not related to the -B option, then it might be due to antialiasing, see the -n option: -n+a. Would help if you have a minimal example of the commands used.

Thanks @PlanetGus and @chhei-s for your replies.
I have some -B[…] options as well as -B[…]g[…]. I attached below the lines where i have it (i’m using grdview after blockmean and surface):

gmt subplot begin 1x2 -M0.1c -Fs8c/0 -R28/43/-28/-10 -JM8c -SCb -SRl+t -Bwesn

gmt grdview -Ccontinuous.cpt -Qs -B+t"T2" -c0,1

gmt colorbar -Dx6.85c/4.35c+w4c/.18c+jTC+e -F+gwhite -Ccontinuous.cpt -B100g25
-B+tcontinuous -Bx -By+lmm

The -n+a option doesn’t seem to work with grdview, or should it be placed with some other command?

Thank you for the help.
João Rocha

@jrocha - indeed, the -n+a doesn’t work in grdview. Have you tried playing with the different -Q options, such as -Qi instead or testing the options mentioned in the Notes section of the grdview page? I’d guess that this is related to your original grid increment and the way grdview is rendering the surface. Other than that I don’t know… sorry.

@chhei-s in fact i’ve changed -Qs to -Qi and the gridlines have disappeared, though there is a lack of resolution with -Qi or that’s the way the -Qi option looks like At least the lines are gone. Anyway i think i’ll try to re-grid with different increments to see how the output will look like.
Thanks a lot.

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