How to unzip LROC CDR images? Options

[TerryH]

I have downloaded some LROC CDR 500MB images but am unable to unzip them. WinZip gives an error message - I suspect the zip file is too big for it. Irfan says it can't read the headers. NASAview seems to unzip them but displays them as completely white images but for a few hints of craters that appear as very pale grey.

Could anyone suggest an unzip program? Ideally I would like to display the images in Photoshop.

Terry.

[JohnVV]

i am guessing that win is defaulting to " help" for a non Microsoft format and tring to use the 15 year old "MS zip" on the r-click menu
garbing a page at ran.
http://wms.lroc.asu.edu/lroc/view_lroc/LRO....0/M107694274LE
-- top left of page--
the EDR
/2009258/NAC/M107694274LE.IMG
the CDR
/2009258/NAC/M107694274LC.IMG
the Tiff
/2009258/M107694274LC_pyr.tif

the top 2 are in PDS .img format , 16 bit
NASAView will open then save it as a 8 bit indexed gif

photoshop should be able to open the tiff
( i do not own a copy of MS adobe Photoshop )
i open them in isis3 ( there is a " almost/sort-of" working microsoft version
i think it is text only -- no GUI , you need to type

also Imagemagick can open the IMG's with some help there is a text header before the image starts in the file
any hex editor ( including MS Visual Studio ) can read the beginning of the img file and you can use the header size there in the ( yes TEXT only) IM program "convert"