When Playing together with Metal and Stars the game fails to get past the loading screen. Upon reaching 50% and transitioning from "Cropping Bitmaps" to "Loading Sprites", the game just closes without an error output. Opening the factorio-current.log only has 3 errors which say that "Prepared sprite registrations are empty" and "No pictures to put in atlas" followed by an error about a failure to display the message dialog (I assume this is where the error should normally be thrown on the screen).

Are both of them the latest versions?

Both mods are using their latest versions as of writing this comment.
Better Starmap Background - 1.1.3
Metal and Stars - 0.1.6

I'm getting the same issue, but I'm loading a lot of mods (just testing for a new multiplayer save).

These are the planets I'm loading:
Cerys
Corrundum
Cubium
Factorio and Conquer: Tiberian Dawn
Lignumis
Moshine
Muluna, Moon of Nauvis
Planet Castra
Planet Maraxsis
Secretas&Frozeta
Tenebris Prime

I'm using this mod to adjust the solar system: Organized Solar System

This is the error in the log:
10.134 Error AtlasBuilder.cpp:157: Prepared sprite registrations are empty: start = 16057, to try = 0, max size = 4096, registered sprites count = 323124
10.134 Atlas: virtual = 0, flags = none
10.134 registration[16057]: padding = 1, dest_width = 4096, dest_height = 4096, filename = Better_Starmap_Background/graphics/icons/starmap_background_star_01.png
10.134 registration[16058]: padding = 1, dest_width = 4096, dest_height = 4096, filename = Better_Starmap_Background/graphics/icons/starmap_background_star_02.png
10.134 registration[16059]: padding = 1, dest_width = 4096, dest_height = 4096, filename = Better_Starmap_Background/graphics/icons/starmap_background_star_03.png
10.134 registration[16060]: padding = 1, dest_width = 4096, dest_height = 4096, filename = Better_Starmap_Background/graphics/icons/starmap_background_star_04.png
10.134 registration[16061]: padding = 1, dest_width = 38, dest_height = 16, filename = space-age/graphics/terrain/space-platform/tile-animations/north-top.png
10.134 Error Util.cpp:81: No pictures to put in atlas.

Maybe you can try this: In the graphics settings, atlas texture size needs to be set to 8192 or 4096？

It doesn't help, no matter what value you set, the error still appears "No pictures to put in atlas"

Same as Hoochie, error doesn't seem to care about texture size setting.

Same here with atlas size 8192 and video memory medium, even with just space age and this mod.

4.942 Created a virtual atlas bitmap (size 4096x512) [none]
4.948 Error AtlasBuilder.cpp:157: Prepared sprite registrations are empty: start = 257, to try = 0, max size = 4096, registered sprites count = 217301
4.948 Atlas: virtual = 1, flags = none
4.948 registration[257]: padding = 1, dest_width = 4096, dest_height = 4096, filename = Better_Starmap_Background/graphics/icons/starmap_background_star_01.png
4.948 registration[258]: padding = 1, dest_width = 4096, dest_height = 4096, filename = Better_Starmap_Background/graphics/icons/starmap_background_star_02.png
4.948 registration[259]: padding = 1, dest_width = 4096, dest_height = 4096, filename = Better_Starmap_Background/graphics/icons/starmap_background_star_03.png
4.948 registration[260]: padding = 1, dest_width = 4096, dest_height = 4096, filename = Better_Starmap_Background/graphics/icons/starmap_background_star_04.png
4.948 registration[261]: padding = 1, dest_width = 512, dest_height = 512, filename = core/graphics/icons/starmap-star.png
4.951 Error Util.cpp:81: No pictures to put in atlas.

However, for me changing video memory usage from medium to high helps

I get the same crash

Also got the similar error:

  23.121 Error AtlasBuilder.cpp:157: Prepared sprite registrations are empty: start = 110870, to try = 0, max size = 4096, registered sprites count = 346517
  23.121      Atlas: virtual = 0, flags = none
  23.122      registration[110870]: padding = 1, dest_width = 4096, dest_height = 4096, filename = __Better_Starmap_Background__/graphics/icons/starmap_background_star_01.png
  23.122      registration[110871]: padding = 1, dest_width = 4096, dest_height = 4096, filename = __Better_Starmap_Background__/graphics/icons/starmap_background_star_02.png
  23.122      registration[110872]: padding = 1, dest_width = 4096, dest_height = 4096, filename = __Better_Starmap_Background__/graphics/icons/starmap_background_star_03.png
  23.122      registration[110873]: padding = 1, dest_width = 4096, dest_height = 4096, filename = __Better_Starmap_Background__/graphics/icons/starmap_background_star_04.png
  23.122      registration[110874]: padding = 1, dest_width = 64, dest_height = 64, filename = __skewer_shattered_planet_assets__/graphics/icons/shattered_planet_approach.png

Adjusting atlas size and so forth seems to make no difference, whether 4096 or 8192 or max.
On another computer it "just loads" when on 8192 or max atlas texture size but has same error on 4096.
They do have some other differing render options, but changing atlas to 4096 reliable caused it on the second computer. Playing with various quality settings on the first computer also had no changes with it.

Same "No pictures to put in atlas" crash for me. Atlas size settings and launch options don't help.

In the new version, I reduced the size of all the images, which might be helpful. If anyone is interested, perhaps you can give it another try.