Dear Dr. June.
Thank you very much for your quick answer.
I’ve been working the whole day on this little project and two situations have developed:
1.- I’ve read the post you provided (Thank you very much I also read Getting ENVI to read your PDS image correctly).
2.- I changed my subject of study and objective.
Now I'll be trying to estimate the age of Enceladus' northern pole with the Buffered Crater Counting Technique. I'll be doing it with the help of ArcGIS' add-ins CraterTools & CraterStats.
This is the best image of the features I was able to find. I uploaded the .img and .lbl (in .txt format) in this post.
I am using T. Kneissl & G. Michael's Crater Size-Frequency Measurements on Linear Features - Buffered Crater Counting in ArcGIS and T. Kneissl et al. New Software Tool for Map-Projection Independent Crater Size-Frequency Determination in ArcGIS as reference.
And following the post you provided (thanks again), I really tried to create my own lunar projections in ENVI, but I was unable to do so. (I didn't find the buttons of the post's steps 3 to 9 in my ENVI software). And I really don't know why.
But I discovered how to do all that in ArcMap. And I even find out that ArcGIS has it's own set of projections and coordinate systems for most of the solar system bodies, Enceladus included.
Sadly it was not a sinusoidal projection. So I had to create my own projection based upon the default one but with a sinusoidal projection for Enceladus.
However, I'm still wondering what to to with the pronounced curvature of my image.
I think I don't really need my image to be georeferenced for the ArcGIS' add-ins to work, but I would really like to know your opinion on what should do in this case.
Should I georeference my image?
Should I change it for one I can easily project in a custom made projection?
Should I try to orthorectificate it?
Or how should I justify the fact that I'm not georeferencing my image?
I include the PDS data & both papers.
Thank you very much in advance for you time.
Please stay safe and be careful.
T. Kneissl & G. Michael Crater Size-Frequency Measurements on Linear Features - Buffered Crater Counting in ArcGIS.pdf
T. Kneissl et al. New Software Tool for Map-Projection Independent Crater Size-Frecuency Determination in ArcGIS.pdf