Need help implementing SEN2COR on an iMac Computer


I would like to compare Landsat OLI and Sentinel BOA reflectances for conifer forests in the southeastern US. I obtained a BOA Landsat scene from USGS. I have installed the SNAP Sentinel 2 Toolbox and have figured out how to perform most of the operations I am used to using on ERDAS Imagine. I have also installed SEN2COR, but have not had any luck getting it to run.

I’m no computer programmer, but I am an experienced user of satellite data. What I would greatly appreciate is if someone could talk me through resolving the error messages I have gotten from SEN2COR. I’m sure the problems I have encountered are not unusual and are probably discussed somewhere on the forum already, but after some preliminary searching I have not run across fixes I can understand.

So, anyone up for a challenge? Here is the first of three error messages" Path does not exist: ‘/bin/L2A_Process’. A virtual heartfelt handshake of thanks for any and all help.

Best Regards, Norm Roller – Ann Arbor

Well, in the hope that seeing the other two error messages will inspire someone to respond with solutions to these problems, here are the second and third error messages.

  1. “Working path does not exist: ‘/Users/Owner/documents/sen2cor’”

  2. “Variable SEN2COR_BIN is not set”

Best Regards, Norm Roller

Dear Norm,

you need to set the paths manually in SNAP as described here:

Hello ABraun,

Many thanks for replying, Sorry to take long to respond but I was out of town. I have looked at the material you referenced and have the following questions: How do I tell which version of SNAP I am running? How do I tell which version of Sen2Cor I am running? Do I need to load Anaconda? It seems like all the material in the links you supplied were for Windows machines; are the instructions for iMacs different?
I may be getting myself in over my head here, since it seems like everyone in the forum is pretty comfortable with their operating systems. I’m obviously not, just an experienced user of well documented applications.

Best regards, Norm

Dear Norm,
you can see the version of SNAP by clicking the Help section in the menu > About SNAP.
The version of sen2cor is shown under Tools > Plugins > Available / Installed

With sen2cor 2.4 you no longer need Anaconda. As written here:

sen2Cor installation packages are provided as standalone installers. For a short introduction of how to install the standalone version of Sen2Cor, read the installation steps described in section 4 of the release note S2-PDGS-MPC-L2A-SRN-V2.5.5.pdf

I agree that the documentation of sen2cor is not ideal, but you have to consider that it is provided for free whereas ATCOR or other commercial ones are professionally marked and supported.