How to calculate the reflectance

I have exported the image to ENVI, how to calculate the reflectance of each band between 0-1.

More information needed:
Which sensor? What data? What product level? What preprocessing was already done?

How can we know? :slight_smile:

sentinel 2a L1C

I have also processed level 1C product to level 2A. I want to get the reflectance between 0 -1.

Level 2A is reflectance, but in Integer. To get it scaled over 0-1, you’ll have to divide by the QUANTIFICATION_VALUE from the metadata, mostly 10000