ok.. simple enough...

i summon snipe hunter..
you solemn the summoning..
can i counter with dark illusion and negate solemn..

im asking because dark illusion says "face up monster"

wouldnt the monster have to be coming onto the field face up to target it with solemn to negate its summoning?

No. Snipe hunter hasn't hit the field yet, since Judgment is trying to negate its summon. Not on the field, so it cannot be targeted, meaning you cannot activate Dark Illusion.

also solemn doesnt target. counter traps generally don target. there are exceptions to the rule though. Yeah Im looking at you negate attack

Negate Attack is the retarded brother that no one knows why the hell he is in the counter-trap family and assume he's adopted.