Hi there: Would you please let me know which MTRDR scene you have been examining and I will take a look at the data and spectral plots and then answer your questions.
PDS Geosciences Node Manager and CRISM Science Team Member
Hi dear community,
I'm working primarly with MTRDR products for mineral identification using ENVI 5.3 + IDL with CAT 7.4 coupled and i have some questions:
1.- Why when i visualize the spectral profile for some scene in any pixel the profile shape is essentially the same only with changes on the data value?. Does that mean there's only one dominant phase per scene?. Even when i use the Browse Products and can distinguish more than one phase (colors) the profile for the default image (true color) keeps its form. I don't know if this is a coincidence for the scenes that i've analyzed or there is something wrong on the procedure that i'm following.
2.- It is enough the interpretation with the continuum removed function or the ratioing process is necessary?. I consider that isn't an easy task find an appropiate denominator ROI. I've tried to emulate some examples from the MICA files but i did not get the same results.
3.- About the custom stretching for Browse Products, when is neccesary fix the minimum value distinct to zero?. I understand that the maximum generally must be thw 99th percentile of the histogram, right?.
4.- How must be selected the right summary parameters for the "Custom Products" when the "Browse Products" are not good enough?
Any help for any question will be very well received, thank you.
I think the only difference between yours and mine is the data ignore value. Since you cannot change -1 to 65535. How about you directly open the .hdr file in NotePad and change -1 to 65535 then save the file? You need close the .img in ENVI otherwise, you are unable to save the .hdr file.