Hi,
when you set the z axis to a log scale in a 2-d histogram, the colors disappear!
I am using root 5.28.00 on os x 10.6.5
thanks
Peter
Simple demo:
{
gStyle->SetPalette(1);
int n=100;
TH2F *histo = new TH2F("testHisto", "testHisto", n, 0, n, n, 0, n);
for (int i=0; i<n; i++)
for (int j=0; j<n; j++)
histo->SetBinContent(i+1,j+1,10*i+10);
TCanvas *c1 = new TCanvas();
c1->Divide(1,2);
c1->cd(1);
histo->Draw("colz");
gPad->SetLogz();
c1->cd(2);
histo->Draw("colz");
}