Can you use scrying magic to see someplace other than your sight would normally allow, perhaps even to a completely different location via an Arcane Connection, and then cast sight range magics as if you were at that location? For example, could you use Eyes of the Flame to fire an arrow over a wall and then blast people through the arrow because you can now see them?
Worse, can you project your image to some far off location with Haunt of the Living Ghost, or Image from the Wizard Torn, and cast magics through this image?
It does not say you can't, but conversely it does say that you can't magically increase the range of Voice range spells. You'd think this logic could be extended to Sight (i.e. it has to be the wizard's natural sight) but then the rules explicitly allow magical items with sight range spells to simulate sight for themselves with an invested InIm effect and thus cast the sight range spell.
Canonically, no. InIm spells don't let you see target, they let you see/perceive/understand depending upon spell an image of the target - a bit like trying to target a Sight range spell through a laptop and webcam. The magical item caveat is a bit of a fiddle to allow justification of targetting, but it still requires that the target be within sight range - the effect invested just allows the item to discriminate between targets and so pick the correct one.
Thanks for the interesting angles on this, everyone.
Extrapolation from the voice limit does make sense, and it could be seen to be down to one of Limit of Essential Nature and the Limit of Arcane Connections. Metaphysically, it has to be your natural voice that carries the magic, and your natural sight that targets the magic. You can't feed magic with magic, right?
I think we have to distinguish the sight you need for targeting and the sight you need for range: sight. I believe the former can be magically enhanced with Intellego - that is a matter of perception and if you have sufficiently precise perception of the target and it's position it doesn't matter how this is achieved - but I'd agree that the latter should be more absolute - there is an unobstructed line of sight between magus and target or the target is not in sight range.
I agree RAW is not clear on the subject, but the existence as well as the description of Opening the Magical Tunnel certainly implies that by itself scrying is not enough to cast through.
In my mind I also think about range Touch spells. I wouldn't let an InIm spell that provides tactile species at range to channel Touch spells. I don't consider the act of perceiving something by feel to have the same metaphysical significance as actually reaching out and making physical contact with a target. The same logic could be applied to spells providing visual species. Seeing is not the same as SEEING.
Spells that Target a sense would be a different story. Since the suffer the limitations of the sense they enhance it stands to reason in my mind that they gain the benefits of said sense. So you could cast a Sight (or Eye) range spell on an invisible target even if you only "see" the target via an InIm target Vison effect. I can't remember (Nobles's Parma) if target Vision effects are the canonical way to grant sight to independent magic items. But in my mind the effects would be related under general rubber magic explanations.
One interesting direction to go in would be to say that it's impossible under current Hermetic theory but targeting through scrying is a possible Breakthrough.