anchor.diff:       integer :: n_dust
   
        integer :: group_id = 999
  +
  +     logical :: use_filters
  +     type(filter), allocatable :: filters(:)
   
     end type image
   
  
positive.code:           call find_image_bin(img,x_image,y_image,ix,iy)
            if(ix >= 1 .and. ix <= img%n_x) then
               if(iy >= 1 .and. iy <= img%n_y) then
                  img%img(inu,ix,iy,im,io,:) = img%img(inu,ix,iy,im,io,:) + img%tmp_stokes * p%energy
                  if(img%uncertainties) then
                     img%img2(inu,ix,iy,im,io,:) = img%img2(inu,ix,iy,im,io,:) + img%tmp_stokes**2._dp * p%energy**2._dp
                     img%imgn(inu,ix,iy,im,io,:) = img%imgn(inu,ix,iy,im,io,:) + 1._dp
                  end if
               end if
  
negative.code:        call error("image_setup", "unexpected value of io_bytes (should be 4 or 8)")
      end select
  
      ! Set up filters
      if(mp_exists_keyword(handle, path, 'use_filters')) then
         call mp_read_keyword(handle, path, 'use_filters',img%use_filters)
         if(img%use_filters) then
            if(img%use_exact_nu) call error("image_setup", "cannot use filters in monochromatic mode")
            ! TODO: also don't allow if using raytracing
            ! TODO: set up filters here
         end if
      else
         img%use_filters = .false.
      end if
  
  
    end subroutine image_setup
  
    subroutine find_sed_bin(img,x_image,y_image,ir)
  