Mask extraction of DEM changes data

[UlisesHuerta]

Hello,
I have a DEM of Rwanda with values that range from 631 - 4434. When I extract using a mask the highest value changes to 4483. Can someone please help me try to figure this one out?
Thanks in advance,
Ulises

[RobertBerger]

Hi Ulises,

Can you calculate the statistics again for your input to make sure the statistics are correct?

Robert

[EricRice]

Hi Ulises,

I have a couple questions.

1. What version are you using? 
2. What tool are you using?  There are many ways to do this...
     - Clip tool
     - Extract by Mask tool from Spatial Analyst
     - Export Data from TOC with selected graphic (the mask)
3. Are you snapping back to original DEM?

Eric

[PeterProkein]

Perhaps related, in Arc10, a simple Right-Click -> Data -> Export Data appears to change datavalues as well.  Source data is in Erdas Imagine format, target data is an Arc GRID.  Source elevation range is -1.264 to 1339.19, target range is -20.567 to 1577.26.  Cellsize wasn't changed so no resampling should have happened.  Not exactly confidence inspiring.