Hi guys, I sure could use some insight on this issue. Sort of a long way around to ask a question but bear in mind I am a beginner.I have been creating some of my own terrain mesh (as he pats himself on the back), and now I am working on creating some Hi-resolution photoreal terrain mesh. Were talkin' 1.2m/pixel. Yes, I am aware of FS2004 limitations with this stuff but I have had some success. I can create it with good results using a "flatten" poly process but of course we all know the world ain't flat.When I create hi-res photomesh I will get these spikes that shoot way up into the air. I can only assume there is no DEM data at those points causing this anomily? Looking at my terrain mesh map it is mostly different shades of green for the land elevations and blue for the water. However there are specs of red and yellew pixels. The reds seem to cause holes when creating "normal" terrain mesh. By using the interpolation feature in SBuilder I was able to fix that problem.But now trying hi-res stuff it appears these spikes occur right on or near those yellow pixels.(the reds ahave been eliminated).So my question really is are those yellows (found all on land next to shorelines and water inland like lakes and canals), are they too lacking data causing my problem? Or are they supposed to be there? If they shouldn't be there, any easy remedy to fix them?Many thanks from an Nubie mesh maker...Clutch

As a follow-up using the SBuilder BSQ viewer I am able to see that the yellow pixels represent negative numbers. So I am using SBuilder to change all negative numbers to zero elevation to see what effect it will have.