The hatch line thickness is the only other option I can think of that would affect the line visibility.
But the hatch thickness looks fine in the shadows.
Certainly seems like the sun is washing it out.
However the sun strength in Archicad seems to have no effect on the sketch render.
Have you tried activating another scene?
Make sure you have your custom scene saved (stored) first so you can go back to it.
You could even export your scene, zip it and post it here and maybe we can have a look at it.
Or take a few screen shots of your settings.
I am using the latest preview build (5002) for version 21 - not sure if updating will make a difference if you haven't done so already.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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