MATLAB eps output different from on screen version using painters renderer -

i have issue when outputting eps version of image matlab. eps looks different on screen version , png output of same image.

the code below, run on matlab r2012b, produces eps file different png. notably grid offset on right hand panel same (random) data flipped axis.

clear close  a=rand(40,20);  figure subplot(1,2,1); imagesc(0.5:19.5,-85.5:2.5:14.0,a); ylim([-6.2 11.1]); set(gca,'fontsize',13);  subplot(1,2,2); imagesc(0.5:19.5,-85.5:2.5:14.0,a); set(gca,'ydir','normal'); ylim([-6.2 11.1]); set(gca,'fontsize',13);  colormap(pink(10)); print('-depsc2','a.eps'); print('-dpng','a.png'); 

any ideas why? error doesn't seem occur if using non-'painters' renderer. , grids fine when axis uses standard direction imagesc, not when flipped.

thanks!