Index: /issm/trunk-jpl/src/m/plot/checkplotoptions.m
===================================================================
--- /issm/trunk-jpl/src/m/plot/checkplotoptions.m	(revision 21065)
+++ /issm/trunk-jpl/src/m/plot/checkplotoptions.m	(revision 21066)
@@ -202,4 +202,5 @@
 if exist(options,'log'),
 	if exist(options,'caxis')
+		options=addfield(options,'caxis_pre',getfieldvalue(options,'caxis'));
 		options=changefieldvalue(options,'caxis',log(getfieldvalue(options,'caxis'))/log(getfieldvalue(options,'log')));
 	end
Index: /issm/trunk-jpl/src/m/plot/processdata.m
===================================================================
--- /issm/trunk-jpl/src/m/plot/processdata.m	(revision 21065)
+++ /issm/trunk-jpl/src/m/plot/processdata.m	(revision 21066)
@@ -171,8 +171,11 @@
 	%log?
 	if exist(options,'log'),
-		%if any(data<=0),
-		%	error('Log option cannot be applied on negative values. Use caxis option (Rignot''s settings: [1.5 max(data)])');
-		%end
-		data=log(data)/log(getfieldvalue(options,'log'));
+		bounds=getfieldvalue(options,'caxis_pre',[min(data(:)) max(data(:))]);
+		data(find(data<bounds(1)))=bounds(1);
+		if any(data<=0),
+			error('Log option cannot be applied on negative values. Use caxis option (Rignot''s settings: [1.5 max(data)])');
+		end
+		pos=find(~isnan(data));
+		data(pos)=log(data(pos))/log(getfieldvalue(options,'log'));
 	end
 end