Ralph Vidal Posted May 25, 2020 Posted May 25, 2020 Hi, I am working with CRISM data on the McLaughlin Crater . I have downloaded following IR dataset images FRT0000CB488_07_IF166L_TRR3 FRT000139F7_07_IF166L_TRR3 FRT000247A0_07_IF166L_TRR3 HRS00006AC4_07_IF175L_TRR3 FRS00029E22_01_IF168L_TRR3 FRS0002B4DA_01_IF168L_TRR3 FRS0002C9DC_01_IF168L_TRR3 FRS0002DB50_01_IF168L_TRR3 FRS0002EF79_01_IF168L_TRR3 FRS0002FF3C_01_IF168L_TRR3 FRS0003134A_01_IF168L_TRR3 FRS00035729_01_IF168L_TRR3 FRS0003640C_01_IF168L_TRR3 FRS0003705A_01_IF168L_TRR3 FRT00009CAE_07_IF166L_TRR3 FRT0000A27C_07_IF166L_TRR3 FRT0000A5AA_07_IF166L_TRR3 FRT0000C42E_07_IF166L_TRR3 FRT0000C6AF_07_IF166L_TRR3 as well as those VNIR images: hsv0001bf65_01_if209s_trr3 hsv0001e87c_01_if209s_trr3 hsv0002e57c_01_if209s_trr3 hsv0003f9e0_01_if209s_trr3 hsv00043b25_07_if209s_trr3 hsv000293cf_01_if209s_trr3 hsv000412d4_03_if209s_trr3 hsv000478c2_03_if209s_trr3 hsv0002003a_01_if209s_trr3 hsv0002246d_03_if209s_trr3 hsv0003793e_01_if209s_trr3 What would be the steps needed to process those images? As far as I understood I need to 1) Convert PDS to CAT ( is it needed ? ) before loading image into Envi 1) ATM correction ( for VNIR images only photometric correction) 2) CIRRUS ( despike + destripe) 3) MRO CRISM remove stripes 4) Flatten summary products ( what does it do ? is it necessary ? ) 5) Apply crism bad band list Are the above steps correct/enough/in the correct order , and is there a script ( IDL whatever ) to process thos images as a batch task ? I am doing a geological map of the McLaughlin crater, using crism's "rock.sli" spectral library to map the geological units. Can this library be used with VNIR data, or only with IR data ? Thanks Ralph Vidal
Ray Arvidson Posted May 28, 2020 Posted May 28, 2020 Hi Ralph: I would be glad to help you through CRISM processing, both as a CRISM Team Member and PDS Geosciences Node Manager. First what version of ENVI/IDL are you using? I suggest not using Classic but rather the new 5 series interface. I use version 5.5.3. Once we are set with ENVI then I can tutor you through the steps using a Zoom session, which I will record so you can play it back as needed. Waiting to hear from you. Ray Arvidson
Ralph Vidal Posted June 10, 2020 Author Posted June 10, 2020 Hi Ray, I finally managed to install ENVI 5.5.3 on my computer. As I wrote before , I intend to use VNIR crism data with the "rocks.sli" spectral library. The first picture ( crism VNIR images overlain on CTX mosaic ) shows the area I want to process . The second pic shows the results using SAM with Bandmax ( threshold of 0.05) applied to one of the VNIR images. Does it make sense ( using only VNIR data with CRISM's "rocks.sli" library ) ? Thanks Ralph
Ray Arvidson Posted June 12, 2020 Posted June 12, 2020 Hi Ralph: Looks like you got pretty far along. Are you using CAT7.4 installed on ENVI 5.5.3? Also, typically, S data for CRISM do not contain as much mineral information as L data. I would use CAT 7.4 and the atmospheric correction in CAT to remove L data gas bands, then generate 2014 IR parameter maps and examine those for the presence of minerals like olivine, pyroxene, sulfates, and clays. Let me know if you downloaded and installed CAT7.4 from our web site. Ray
Ralph Vidal Posted June 12, 2020 Author Posted June 12, 2020 Hi Ray, yes, I got the CAT 7.4 from your website and installed it on ENVI 5.5.3 ( CAT does not appear on the menu when using envi classic, but it does not matter, as I am not using the classic gui ). I am working with the S data because there is not enough L data for this crater . Where L data is available , I will use it , otherwise I have use the S data . It seems the CAT tool would only identify ferric phases, that is why I am trying to use ENVI's spectral angle mapping tool with the "rocks.sli" library. The CRISM data files I get from http://themis-data.asu.edu/ ( for example http://themis-data.asu.edu/viewer/crism#P=FRT0000A5AA_07_IF166L_TRR3&T=2 ) - not the processed ones , but the ones with the link on the page ( ddr1, lbl, .img etc) Ralph
Ray Arvidson Posted June 16, 2020 Posted June 16, 2020 Hi Ralph: I hope our Zoom session and discussion of how to process and interpret CRISM data was useful. Unfortunately, I forgot to check the button saying record this session. Anyway, if you have any other questions let me know by email or via the Forum. Best of luck with your master's degree research. Remember to think about where in the crater you might expect some underlying bedrock to be exposed. Ray
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