# Color of figure keeps changing

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.

• Please include the code/data that you used to generate the picture and export it to PDF. I don't think we would be able to help you otherwise. – MarcoB Mar 16 '16 at 22:44
• Could be a problem with the PDF viewer. What OS are you on, what Mathematica version, how do you invoke latex to create the PDF (pdflatex, xetex, via dvips, ...)? – Jens Mar 17 '16 at 2:30
• You might also want to look at these discussions, which may be relevant to your problem: (2629), (18625), and (644). – MarcoB Mar 17 '16 at 3:55
• I'm using Mathematica 10.2. I see the same problem both on the Preview and Skim viewers on MacOS 10.11. My friend, with a version of Windows 10, also see the same thing (I don't know what viewer he is using though). I don't think it is related to LaTeX (I use pdflatex) as when I open the PDF image by itself, I still see the same thing happening. @MarcoB, thanks, this is indeed useful, as it seems that I also have those weird polygons in my regions. – AnSy Mar 17 '16 at 14:08