I can't say I have really used the CAVIS bands to assist with atmospheric correction in ENVI. QUac does not use them but you could use the cirrus band for aerosol retrieval in the Multispectral Settings->Kauffman-Tanare aerosol retrieval settings. You would need to layer stack the cirrus band (1367 - 1383 nm) with the VNIR-SWIR bands first before running FLAASH with this setting. In generally, users don't bother with the CAVIS bands and just run FLAASH or Quac on the standard VNIR-SWIR bands.

Thank you Mari for your quick reply,
I am really confused with this subject, since my satellite image provider told me that DG does not give the CAVIS bands but instead they apply atmospheric correction to the image that I ordered, using CAVIS bands and sent that corrected image to me.
The advantage of this process is: if there is a cloud, haze or other atmospheric things on the image, they will recover it to a certain amount.

I am going to make spectral analysis for mapping alteration in the region, so atmospheric correction is too important for me. Do you think I might ask them to do with CAVIS bands or better to do by myself?

Kind Regards

Aysegul

I am not sure what method they use for atmospheric correction. Perhaps they use ENVI to do it :) But if they provided images to you that were already atmospherically corrected, then I don't believe you would need to apply another correction in ENVI. If you did want to, then you should use Quac since it will accept TOA, DN and other units for input while FLAASH expects uncorrected radiance images.

Thank you so much Mari for your advices.

Kind Regards

Aysegul