I'll try to make this one short, and I only had a quick glance at Fly Casual, though it goes beyond that book.

There are now quite a few pieces of equipment, including Nightwing Coating (Fly Casual), Whisperthrust Engines (Fly Casual), as well as Electronic Countermeasure Suite (Core), that seem to affect sensor ranges, being seen or not, etc. (No such attachment exists to extend sensor range yet, only comms.)

We also have Stygian Cloaking devices on the (admittedly rare) TIE Phantom, and a few other ships that have innate cloaking abilities that can be activated.

Ship sensors have a certain range that they appear to be able to "see" at. «Sensors grant a vehicle's crew a constantly updated, 360-degree view of their immediate surroundings. Sensors operate at different range bands depending on their ship and relative strength, and although powerful, can be fooled or jammed altogether by numerous technologies.» Also, the component tables in the vehicle chapter mention that if the sensors «are knocked offline completely», then «the ship is effectively blind until the sensors are rebooted or repaired».

Also, weapons in the game operate within range bands, and within those, enemies can be shot.

I'd like to know how all this ties together, because it is getting a bit confusing when you start putting those elements together at once. Here's a meli-melo of some juicy rules questions:

1. What do ships actually see in space? How far can, let's say, a Customs frigate detect you before it gets into Close range to see you have the wrong transponder code? Or a suspicious patrol ship of any kind, how much warning do they get? Sensor-range limited or further than that? I *am* assuming that Capital ship *would* share sensor info with their starfighters, or else snubfighters would be pretty blind (except... eyes?), if it's the case that sensors define the limit for *seeing* each other.
2. Can a ship make another ship essentially "blind" by jamming its sensors? (assuming eyesight is out of the equation)
3. Does the Electronic Countermeasure Suite "autoblinds" enemies or is this already taken into consideration with the Silhouette reduction?
4. Is Nightwing Coating an awesome sneaking tool or just an expensive piece of fluff text, and by that I mean, are you invisible to other ships as long as you are beyond their sensor range?
5. Can you shoot down ships from beyond their eyesight? (Of couse, that's a question from a PC's standpoint, or for sadistic GMs...)
6. Before coming into each other's range, are ships even aware of each others existence? Strange question at first glance, but if you look at sensor ranges... except two ships (JumpMaster 5000 and Armos Modular Transport, and yes, I actually did search the web for that) none have Extreme range, Long range is mostly for Capital ships, Medium for freighters and PC-friendly ships, and Short (and sometimes Close) for anything smaller. If they can only see within their sensor range, it seems... well... weird, kind of like a random encounter a la Final Fantasy: Poof! an enemy ship!
7. Whisperthrust Engines can help with your... Stealth checks in space? Should I assume Stealth checks exist in space? Like anyone, hiding in Asteroids or in the... back... of the control tower... of an ISD... seems movie-feasible (or at least fun!), but I'd be glad to know how.
8. The Sniper Shot talent from the Advanced Targeting Array seems to increase the likelihood of being able to shoot a ship that has yet to get you in their sensor range, or does it? Also, it often means you can shoot further than you can see, if we go by the same logic...
9. Does this mean that a Nightwing Coat-ed freighter cannot be shot at from Long range by an ISD's turbolasers because the ISD's sensor range is considered medium? Also, if the ISD is unaware of the freighter's existence, it could not justifiably do an active sensor sweep to increase its range back to long, if you get the conundrum...

(Success! I've managed to stay below 10 questions this time around!)

We can use no reference point in reality, since SW Physics are quite different. In the Real World, sensors could pick signals from beyond a solar system, but those signals would be delayed by lightspeed and reduced in intensity in a manner inversely proportional to the square of the distance from the source of that physical quantity. But SW is not Real World Physics. Star Wars sensors shown in the books work in an entirely different way, or else Han would never have been able to hide in The Empire Strikes Back, and Boba Fett would have been noticed very easily by Han.The above questions are thus distinct from our real world experience, and unlike ground or air-based combat, we can't simply *assume* we would intuitively know.

TL;DR version: are we in a "submarine paradigm" where radar range defines our sight, or an "open sea paradigm" where some stuff can go under the surface? What is our metaphor for adjudicating sight / ranges / stealth / jamming / sensors in space ?

Edit: Did I just sound like a philosophy major there? ****.

For myself, I've always considered these sensor ranges to "see" something to be "see and identify." You can see farther, but you don't know if it's a rock, a ship, some debris, or just sensor static. The farther away, the worse it gets. The fainter the signal, the harder to identify.

1. Ships see lots of things, but only within their sensor range can they identify what it is. The closer to sensor range, the better the "guess" of what it is. I'd say that you can tell a ship from a rock one range band out from your sensor range. You should be able to tell a large capital ship from something smaller. You might miss a fighter (but half a dozen in formation would stand out).

2. I would think yes, absolutely, a ship can be blinded by jamming its sensors, but see #3.

3. I think the ECM suite does the best it can to blind enemies, but for whatever reason, totally blinding sensors is hard, so it just makes it harder to pinpoint the ship doing the jamming.

4. I think the nightwing coating makes it harder to see you visually, and makes you "dim" to sensors so they don't work as well.

5. Sure. Star Wars weapons aren't terribly precise though, so the first volley from long range isn't likely to hit solidly. "Hey! Somebody's shooting at us!" "Who? Where?" "Can't tell, they're out of sensor range." But you could still tell more or less where the fire came from, and head the other way.

6. As I've said above, ships are probably aware of other ships out there, from drive emissions if nothing else, but not enough to identify. Possibly with some Computers rolls (hard I'd think) they could plot a vector for another ship and take a guess at the range and/or size of the other ship about one range band out. At Extreme, I'd think it would be no more then a "I think there's another ship out there." unless it was something like a Star Destroyer, which, you have to admit, kinda stands out.

7. I always assume that the primary method to identifying a ship is a combination of engine emissions and the physical silhouette. At long range, it's more engine emissions. Whisperthrust damps that down so it's harder to detect.

8. No clue. Haven't seen those. Book/page reference and I'll look it up and render an opinion.

9. I would say if the Star Destroyer didn't know the freighter was out there and wasn't actively sweeping for some other reason, it has a good chance of not seeing it. If it knew the freighter was there, and had some eyes on it somehow, it could fire volleys of turbolasers and maybe hit it, but not likely because they can't lock on at that range due to the coating. Not that turbolasers are inherently that accurate anyway.

Now, to add more confusion, in the EU there are a couple references to doing a "sensor focus." This seems to be a way to pin down something you can't identify normally, and at longer ranges. With this in mind, I'd say sensors normally operate 360° at a certain range band. If you have time, and a successful Computers roll, then you can "focus" on an area at least out to the next range band and identify it as if it were in range. Make the check even harder to go out two range bands. Setback dice for anything that makes it harder, like lots of other ships around, a hyper-active sun, asteroids in the way, etc.

I've had the same headaches on sensors and have put up similar questions in threads. The basic idea that I run with is that ships can detect things beyond their sensor range, but no real detail is discerned. Within sensor range, details detected depends upon the Computers roll, but can include things like critical hits that the target has suffered, presence of life signs, most Attachments, etc.

Holy Moses that's not short! I'd hate to see your definition of long!

Though it did remind me of a part in my last game where they had a ship slowly coming at them and a player was asking how far can I see out the window. I said "pick up your visual scanning" lol!

To elaborate on Admiral Terghon's answers, one has to remember that space is really really big and really quite dark. To put that in perspective, a large capital ship like a star destroyer is nearly indistinguishable, visually, from a star from long range and beyond. Smaller capital ships are tough to see even at medium range. I posted something about this on a previous thread (one that HappyDaze might remember) about sensor ranges. If you do the math you'll find that you pretty much can't see anything in space.

Sensor Range is really odd