Hello Mr Patterson,
thank you for the quick reply. it is much appreciated.
The data for the raster was actually an ASCII acquired using a white light interferometer and then converted and prepared for ArcGIS using Matlab. Later it was imported to ArcGIS using the tool ASCII to raster. Then this resulting raster is converted to data points using the tool raster to point and finally it the points scatter is interpolated back to raster using natural neighbor.
Therefore these raster aren't geologically referenced. But I know the distance from two points, namely the dimension of the data.
I am still confused how I should go on and tell ArcGIS that this distance from these two points in pixels are this much in µm and set the scale as a result. I thought it would be a simple process to do so just like ImageJ. Is it still necessary to project the data with a geographic dataframe?
Attached is how one of these final raster look like. I apologize that the legend is not included, but the hillshade effect would hopefully make it clear that the green and lighter colored regions form the depression (crater) that I want to calculate its volume using the cut/fill tool. A profile has been drawn across to further explain this.
Thank you in advance and I hope you can assist me further.
Until then let's keep making the world a happier place
Hasso