Nebulae, visibility, and skulking...

[Possum]

I have a very old set of SE4 notes, dated April 2001, in which Atrocities is quoted as saying...

The cyan and violett nebulaes also obscure to level 3, so unless you don't have a level 4 sensor (below that you won't see anything in nebulaes) you can't detect things in violett, cyan and orange nebulaes. Even with level 4 sensor you will be blind like a mole in red and green nebulaes.
Summary:

Obscuration to level 3 (need level 4 sensor):
violett, cyan and orange nebulaes

Obscuration to level 4 (obscures everything):
green

Obscuration to level 5 (obscures everything):
red

Now, I am very fond of playing with Ancient type galaxies, so I deal with nebulae quite a bit.

And I have found that, contrary to the above, I seem to be able to see enemy ships and planets in all nebulae sectors once I have Hyper Optics III.

This is with SE4 Classic, patch Version 1.49

Would anybody care to comment on this?