ERROR: MethodError: no method matching length(::Nothing)

[denfc]

Here's the full code:

using AstroImages

AstroImages.set_cmap!(nothing)
antred = AstroImage(download("http://www.astro.uvic.ca/~wthompson/astroimages/fits/antenae/red.fits"))
antgreen = AstroImage(download("http://www.astro.uvic.ca/~wthompson/astroimages/fits/antenae/green.fits"))
rgb2 = composecolors(
    [antred, antgreen]
    )

Running Julia Version 1.11.3 in VSCode through WSL2 (same error when excuting directly in WSL2 without using VSCode) , the separate images can be viewed when after the error, just antred, for example, is typed into the REPL. Here's the full error message:

ERROR: MethodError: no method matching length(::Nothing)
The function `length` exists, but no method is defined for this combination of argument types.

Closest candidates are:
  length(::FITSIO.FITSHeader)
   @ FITSIO ~/.julia/packages/FITSIO/VqV3x/src/header.jl:351
  length(::DimensionalData.Dimensions.Lookups.NoMetadata)
   @ DimensionalData ~/.julia/packages/DimensionalData/VxDQB/src/Lookups/metadata.jl:84
  length(::Core.SimpleVector)
   @ Base essentials.jl:933
  ...

Stacktrace:
 [1] composecolors(images::Vector{…}, cmap::Nothing; clims::Percent, stretch::Function, contrast::Float64, bias::Float64, multiplier::Float64)
   @ AstroImages ~/.julia/packages/AstroImages/eSsEw/src/ccd2rgb.jl:59
 [2] composecolors
   @ ~/.julia/packages/AstroImages/eSsEw/src/ccd2rgb.jl:41 [inlined]
 [3] composecolors(images::Vector{AstroImageMat{Float32, Tuple{X{…}, Y{…}}, Tuple{}, Matrix{Float32}, Tuple{X{…}, Y{…}}}})
   @ AstroImages ~/.julia/packages/AstroImages/eSsEw/src/ccd2rgb.jl:41
 [4] top-level scope
   @ ~/Gitted/Fractals/tests/Untitled-1.jl:6
Some type information was truncated. Use `show(err)` to see complete types.

What do you think is happening? Is a work around possible on my end? Many thanks!

-- dfc