Dear community, I have following problem. I want to stack two (or more) masks (each with three pixel values: 0,11 and 14) with the help of ENVI+IDL. My testcode works at now with only 2 masks whose pixel-sizes and scene-sizes are different (for that reason the /EXCLUSIVE-command). The code works right until the last few lines. I want to get an three-dimensional array (img_stacked) with the two band-layers each with the same x and y dimension (the one from the bigger mask). I'm an IDL-beginner and would be glad about your help. Thanks My code: pro layer_stack, out_name mask_2000 = envi_pickfile(title='Pick a TIFF file from year 2000', $ filter='*.tif') if (mask_2000 eq '') then return print, 'The selected filename is: ', mask_2000 mask_1990 = envi_pickfile(title='Pick a TIFF file from year 1990', $ filter='*.tif') if (mask_1990 eq '') then return print, 'The selected filename is: ', mask_1990 envi_open_file, mask_2000, r_fid = t_fid if (t_fid eq -1) then begin envi_batch_exit return endif envi_open_file, mask_1990, r_fid = d_fid if (d_fid eq -1) then begin envi_batch_exit return endif ENVI_FILE_QUERY, t_fid, $ ns=t_ns, nl=t_nl, nb=t_nb ; ns = Number of samples; nl = Number of lines, nb = Number of bands ENVI_FILE_QUERY, d_fid, $ ns=d_ns, nl=d_nl, nb=d_nb ; nb = t_nb + d_nb ; Sum of bands fid = lonarr(nb) pos = lonarr(nb) dims = lonarr(5, nb) ; for i = 0L, t_nb-1 do begin fid[i] = t_fid pos[i] = i dims[0,i] = [-1,0,d_ns-1,0,d_nl-1] endfor ; for i = t_nb, nb-1 do begin fid[i] = d_fid pos[i] = i-t_nb dims[0,i] = [-1,0,d_ns-1,0,d_nl-1] endfor ; out_proj = envi_get_projection(fid = t_fid, $ pixel_size = out_ps) out_name = 'C:\folder\subfolder\...' out_dt = 1 ; envi_doit, 'envi_layer_stacking_doit', $ fid = fid, pos = pos, dims = dims, $ /EXCLUSIVE, out_dt = out_dt, out_name = out_name, $ interp = 0, out_ps = out_ps, $ out_proj = out_proj, r_fid = r_fid ; ; ENVI_FILE_QUERY, r_fid, $ ; dims=dims img_stacked = ENVI_GET_DATA(fid = r_fid, dims = dims, pos = 0) print, '' end