I'm not sure this should be posted here, but I don't know where else to ask this question. Please feel free to refer to another more relevant SE if necessary.
I plotted a figure with Mathematica, and then saved it as a PDF. I enclosed it in my article, written in LaTeX. But the problem is that the image displayed has some weird coloring, which is not the original. See for yourself:
The first image is how it should look like, the second one is how it does look like in my paper. (Those are a close up of the region of interest.) Note that this weird coloring also happens when I open the pdf image itself, and I tried different pdf viewers, and I also saw on my advisor's computer the same glitch, so I don't think the problem comes from LaTeX/my computer. Also, when I zoom in/out, the right coloring appears for some time (sometimes a few seconds, sometimes just a split moment), and then goes back to the weird yellow color.
Any idea?
Edit Minimal code that shows the problem:
As = Exp[3.089] 10^(-10);
ns = 0.96;
kstar = 0.05;
k0 = 0.008;
Ampk0 = As (k0/kstar)^(ns - 1);
ratiok = kstar/k0;
Nmax = 350;
fnlVala = 1;
PlotPts =
20 (*20 is quick but less nice, 60 takes times but looks good*);
C2nl[nu_] := -((3^(3/2) 2^(3 nu - 1/2) Gamma[nu])/(
4^nu \[Pi] BesselY[nu, 8/27]));
zetaL3[nu_, Ne_] := 3 Sqrt[Ampk0 (1 - Exp[-Ne (3 - 2 nu + ns - 1)])/(3 - 2 nu + ns - 1)]
deltar3[nu_, Ne_, fnl_] := Abs[(1 + 2^-3 (fnl C2nl[nu] (kstar/k0)^(nu - 3/2) zetaL3[nu, Ne])^2)/(1 + 2 fnl C2nl[nu] (kstar/k0)^(nu - 3/2) zetaL3[nu, Ne]) - 1];
deltans3[nu_, fnl_, Ne_] := (3/2 - nu) fnl/ns C2nl[nu] (2 zetaL3[nu, Ne])/(1 + 2 fnl C2nl[nu] (kstar/k0)^(nu - 3/2) zetaL3[nu, Ne])
Mesh3 = ParametricPlot[{deltans3[x, fnlVala, y],
deltar3[x, y, fnlVala]}, {x, 1.46, 1.5}, {y, 0, Nmax},
PlotStyle -> {{Blue,Opacity[0.3]}}, Mesh -> {39, 13},
MeshStyle -> {{RGBColor[0., 0., 0.51], Opacity[0.5], Dotted}},
PlotPoints -> PlotPts, AspectRatio -> 1,
Frame -> True,(*FrameLabel\[Rule]{ToExpression["n_s",TeXForm,
HoldForm],ToExpression["\[CapitalDelta]r/r",TeXForm,HoldForm]}*)
RotateLabel -> False, LabelStyle -> Directive[Bold, 11],
PlotRange -> All, Axes -> False];
Show[Mesh3]
I think the problem is that Mathematica exports a very large PDF file, and the colored surfaces are actually a collection of small rectangles-ish, which I think is inefficient.
