I was looking through the SR4 BBB and I notice that only a few cyberware pieces require a Perception Test (usually 4) to detect them. This pertained mostly to the "hidden" cyberware. This got me to wondering. What is the noticability of cyberware?

Cyberware such as a datajack could be easily spotted but what about an implanted commlink? If someone doesn't have a Cyberware Scanner handy and is looking at my character, how can they tell what cyberware they have? What about mods for cybereyes or cyberears? If I'm staring at a Lone Star cop after he pulled me over for speeding, how does he know that I have illegal Retinal Modification and an unlicensed Smartlink on my cybereyes? What about those cyberarm gyromounts that I'm wearing a long-sleeve t-shirt and jacket over? What about my Wired Reflexes 3 that I have turned off? Could someone just glance over at me, take an Observe in Detail and with enough successes know all about every single piece of cyberware I have?

I guess this also extends to Restricted and Forbidden gear as well. How would a cop know that my commlink has a hot sim module? Is it SOP for a cop to try to run a BTL on my link so he can tell? How about hacking programs? What if they're hidden on my jacket until I load them for use into my commlink?

Also on a side note: What about assensing? On 2 successes they know I have cyberware, but then 5+ successes tells them that I have alpha, beta, bioware and delta cyberware? Would delta cyberware only show up on 5+ successes on an assensing test then? Just a question that's been rattling around in my head for awhile.

To the last question... the delta might only show up on 5+, but they would know your essence was reduced. Ware is the most common reason for that, followed by random other stuff like vampires, drug abuse, etc.

As for the hotsim module, it probably wouldn't be noticible until they either test it with a program of some sort or take it apart. Thus if you tried to get a legitimate business dealer to repair your hotsim comm he would call the star on you unless you bribed or threatened him not to.
Assensing says it reveals the presense and location of implants. Your average mage who avoids cyberlike the plague would show up as clean, while your hacker with just a datajack would be presense of cyberware, right temple. It would be easy to guess what it is from the location, though somethigns could get ambigious (Is that a cranial bomb or an implanted commlink?)

I don't think they could detect internal cyberware with just normal sight and not a cyberware scanner. The retinal duplication would not be evident as a scanner is requierd to even see the retina in the first place. A cyberarm mount may not even need the shirt, as they are described as popping out of the arm, not always out there, thus it would be a thresholdr 4 if ruled visible at all (maybe there's something wrong with the "skin" of the cyberarm arround that part).

actually, i would suspect drug abuse is probably more common in general than 'ware.

now, the most common reason for essence loss in healthy individuals such as shadowrunners tend to be, that's a whole different situation... but as a general rule, probably drug abuse acounts for more essence loss than 'ware, imo.

anyways, as to the original question, just use common sense. your gyro mount presumably only comes out to play when it's needed imo (you can get a gyro mount in a real looking arm... which says to me it must be "retractable" so to speak).

most cyberware will either be immediately visible on any inspection, or undetectable to normal detection (though extremely close inspection might reveal it, for example noticing the spot where your combat spurs come out of, but would probably require inspection within a few centimeters).

totally internal stuff (internal commlink, wired reflexes not turned on, bone lacing, etc) would not be visible at all directly (though someone might notice if you move funny or something). no amount of normal perception should be able to locate such 'ware.

as far as licenses and whatever, not necessarily. he may very well be able to tell that you have cybereyes. if he had an appropriate scanner, he might even be able to detect what is in those cybereyes. he could possibly tell whether it is legal or not, simply because legal 'ware would be broadcasting itself and it's license. if he can't spot the 'ware, however, he won't know any different.

programs should not be obvious unless he can at least perceive your persona (if the program is running) or the inside of your storage device (ie he would have to hack in, if it is just stored) and then make enough hits on a matrix perception test to spot it. so most likely, no, unless you're actively running around with illegal programs in use actively all the time.

Cyberware scanners do this p 325

"Millimeter wave detection systems, also known as
cyberware scanners, process video taken in the millimeter
wave spectrum to identify the energy signature of cyberware
and concealed items (specifically weapons) on a person.
These devices can “see through” thick layers of clothing and
other concealment to identify items from a distance of 15
meters away. To determine if the detector scans cyberware
or a prohibited item, roll the Device rating and compare
the hits scored to the thresholds given on the Cyberware
Scanner Table. Millimeter wave scans can detect any nonbiological
item by its shape and composition, assuming
the item is listed in the device’s database. If the threshold
is reached, the scanner detects the item/implant and notes
its general locations and type; additional hits provide more
detail (function, model, grade, etc.)."

The Cyberware Scanner Table on p 255 gives us a pattern where, the higher the grade, the higher the threshold, but the more pieces of cyberware, the higher the pool used to detect cyberware.

Given "Millimeter wave scans can detect any nonbiological
item by its shape and composition, assuming
the item is listed in the device’s database." it's likely only bioware is undetected. But pretty any one loaded with more then a few peices of cyberware is likely to be detected by a cyberware scanner.

Additional hits would give you the added info, such as if the hot sim module was included. So it's fairly reasonable to think some illegal attachments or mods might not be revealed without deeper inspection.