The ASCII file for the sale factors could be as simple as a single column, containing one scale factor value for each band in the dataset. Or it could contain more than one column, tab delimited. FLAASH will give you a chance to choose which column contains the scale factors. To figure out what exactly the scale factors should be, you will need to know what units the radiance Hyperion data file is in. The scale factor will be the value that you need to divide the pixel values by to get them into units of µW/(cm2 * nm* sr). I'm not an expert in Hyperion data products, so I don't know if perhaps Hyperion data can be distributed with different radiance units. In that case, it would make sense that some Hyperion data would need one scale factor, and other Hyperion data might need a different scale factor. This is something your data provider should be able to tell you. - Peg

Than you Peg. I got the solution. Now I have a question ...There is a FLAASH parameter (Ground Elevation km)... do you know which type of images I can use to calculate that parameter??. I have no access to the area so I don't know the elevation. Thanks ;-)

It doesn't have to be a super accurate elevation value, and it is only a single (hopefully representative) elevation value for the area. Do you have any colleagues that have collected GPS data in the area, or derived or ordered digital elevation images of the area? That may be a good source of elevation information. If there is a city in the scene, then the elevation of that city has probably been measured and published somewhere on the internet. If it is not a terribly remote area, then you may be able to find other internet resources that publish the elevation. Otherwise, you could look at one of the global elevation datasets that are available to the public. For example, there is the SRTM data (http://eros.usgs.gov/#/Fi...ata_Available/SRTM), or the GTOPO30 data (http://eros.usgs.gov/#/Fi...lable/gtopo30_info). Those should be able to give you a ballpark sense for the elevation in your study area. - Peg