Question about generating Moon Mineralogy Mapper (M³) Level 2 products with ISIS

[gmessinios]

Hello everyone,

First of all, thank you for all the work that has gone into ISIS. I have been using it extensively for processing and georeferencing Moon Mineralogy Mapper (M³) data, and it has been extremely helpful.

I have a question regarding the processing workflow of Chandrayaan-1 M³ data.

From the ISIS documentation, I understand that chan1m32isis imports the M³ Level 0 (L0) or Level 1B (L1B) products into ISIS cubes while preserving the radiance values and the associated geometry.

However, I have not been able to determine whether ISIS provides a complete workflow for converting M³ Level 1B data into the official M³ Level 2 (reflectance) products distributed through the PDS while preserving the ISIS geometric information and map projection capabilities.

My main objective is to create a georeferenced Level 2 M³ mosaic within the ISIS environment. My intended workflow is to start from the M³ Level 1B products (which ISIS accepts as input), perform the required geometric processing and mosaicking within ISIS, and then convert the final mosaic cube into a Level 2 reflectance product (if possible). Therefore, I would like to understand whether ISIS provides the necessary capabilities to perform the Level 1B to Level 2 conversion.

So, my questions are:

1. Is it possible to convert an M³ Level 1B ISIS cube (or a final mosaic generated from multiple Level 1B cubes) into the official M³ Level 2 products using only ISIS software?
2. If the answer is yes, what is the recommended processing workflow (i.e., the sequence of ISIS functions that I need to use)?
3. If the answer is no, is the Level 2 processing pipeline implemented in another tool or workflow recommended by the ISIS developers?

Any clarification would be greatly appreciated.

Thank you very much for your time!

Kind regards,

George Messinios

[Kelvinrr]

Hi,

Im trying to understand what you are asking for since there might be difference in how we use some terms.

In the ISIS environment, level 2 is simply used to describe a map projected image (e.g., the results of ISIS's cam2map or ASP's map_project). But in this context, it seems Level 2 refers to a reflectance image with geometry?

What I think you are asking is if there is a way to calibrate the L1B images into reflectance using ISIS. Right now, ISIS does not have a M3 calibration app for that. I don't know the history as to why, but if I understand the question correctly, I can probably figure out how to implement it in ISIS. The methodology is out there, but it seems it was never implemented. Digging into it, there seems to be some legacy IDL floating around. You could always open an issue to add this functionality into ISIS and we can work on it, if there is a need for it. That is, if the existing Level 2 M3 images are not enough.

[gmessinios]

Hi,

Yes, you understood my question correctly. Sorry if my original question was not clear enough.

By Level 2, I was referring to the official M³ Level 2 reflectance products distributed through the PDS, rather than the ISIS terminology for map-projected products.

Thank you very much for the clarification and for taking the time to look into it. I really appreciate your explanation.

Kind regards,

George Messinios

[Kelvinrr]

Alright, I'll leave this as is, if for whatever reason you need this implemented feel free to make an issue into ISIS requesting it.