Ok, what exactly CAN we target with spells - what SENSES can we use and what modification to them applies? The below list is my interpretation of the rules and might be completely wrong or a misinterpretation of the rules.
In SR4 there seems to have been a step away from the Optical/Digital sight for mages but what exactly applies as there are now external senses (goggles) with added digital visual aids.
Basic RAW Senses
Touch
Visual
Astral Sight
Cybernetic
Eyeware + Visual Mods, (Low Light, Thermo etc)
Bioware
Trolls Eyes
Cats Eyes
Gear
Lenses*
Glasses*
Goggles*
Smartgun Link in Glasses, Goggles or Lenses**
*These are external gear and have no essence cost - the addons for low light and thermo or even magnification are not a natural sense and is an image display that overlays your natural vision and obstructs your targeting.
**The Smartgun link requires an image link to display AR data which basically makes it a transparent computer screen and makes it an electrinic image also obstructing the view.
Indirect Combat Spells (Follows shooting/ranged combat rules)
All of the above
Echolocation
Radar Sensor
Thermosense Organs
Indirect Combat Spells basically uses a list of its own as it is a form of ranged combat.
They could theoretically use a basic perception test to detect an enemy and blind fire at them.
Have I missed something?