As you may have noticed, most commlinks have holoprojectors. The holographic image they send is probably of a better quality than the Star Wars version, but still if this is to be used instead of a screen the image cannot be transcluent. The BBB says the threshold to notice that a holographic image is unreal is just 2 on a perception check, but how about using it to block line of sight?

The party hacker in my campaign (Life in the Barrens) used this trick in a narrow alley in Kowloon walled city to disprupt the line of sight of a Triad sniper f firing from a window. I still allowed the sniper to fire at them, but with -6 blind fire penalty on everyone taking full cover behind the holographic wall.

That worked pretty well, considering the party tank (Trog) had been hit twice with APDS and taken 11 damage (and drain bramage) and Uzz (gunslinger adept) was missing!

But is this a valid use of the holographic projector?

i don't know that the holoprojector on your commlink would be able to project an object quite as large as a full-scale wall. maybe one of the actual separate devices, but even then that's pretty danged big... i'd probably ad hoc a more expensive, larger, less convenient model personally. but that's just me.

I think it's a pretty smart tactic for the characters to come up with on the fly and I would have allowed it on that basis alone, but I might have only given them a -4 benefit from the sniper. After the fact, I might warn them that while it was a good idea that maybe it's a bit too much, but if they want to tinker with equipment, they can probably rig up a device that will actually give them the full -6 in the future.

Vlad

Well the character had experimented with this tactic before, and had preinstalled the holowall. If he needed to mod the holoprojector somewhat to be able to do this, he would have already. So far he has only been able to fool a few gangers and helped himself from being targeted, at other times it has failed horribly to fool people.

Most people have barely 6 Perception dice pool. If they are distracted, it is a -2 DP. Meaning they'd have 4 dice for Threshold 2.

Interesting tactic. Definitely bonus karma for creativity if the player had the foresight to mod his comm.

I don't think I would allow it on a standard commlink though. I have always imagined the "micro trid / holo projector" on a commlink to produce a small holo image, not something large enough to hide behind. Kind of like the difference between a camera phone and a professional camera. For a larger image you would need the dedicated holo projector or a modified comm.

i imagine a drone with something like that would come in handy O.o
holo over drone to conceal drone, holo out somewhere else to play sitting duck . .

And that's already somebody trained in Perception:

Joe Average has Intuition 3 and Perception 0, leaving him with 2 dice, 0 if he's distracted...

Don't forget thermographic vision, which is natural for dwarves and troll, and can see right through the wall.

Hmmm... sentry gun with built in holo projector... Muahahaha...

build in an personafix-chip and you have the turrets from portal *g*

Well I'll be sure to congratulate the player for his ingenuity, perhaps even award him 2 bonus karma for basically saving his team this way. On the other hand, I agree a typical commlink shouldn't be able to do this, but I think he bought one of the more expensive ones and modded it, and either way he would have modified it with an improved projector if he had the chance so I guess I'll just charge him 2k nuyen for the mod retroactively. Sounds fair?

Otherwise I agree threshold 2 is hard for average joe, but that's not an enemy he needs to use this defense against. Last foe was "good merge" ant spirits with security helmets and vision enhancements... they didn't have a problem seeing through it and the hacker was shot down easily (needed to burn edge).

Since the hacker in question doesen't have any armor besides his armor vest (+cham suit) he wants to find other ways from being insta-gibbed when a foe fires a burst or two at him. Cover isn't always an option.

but maybe with SR4's advances in price decay, ruthenium-polymere-suit is? O.o
cover needn't be, concealment is almost as good as he shows with his project *g*

Yes as said he as a chameleon suit (ruthenium polymere I guess), but I don't equate that with inivisibility (although the player sometimes likes to think so). And as someone pointed out, the "false wall" is countered or at least party negated by thermographic vision, and as an extention, ultrasound.

It might only have a short charge as generally it only deals with very very small images. If you have an entire wall then I think it would drain within a few seconds if their battery is fully charged. At least this gives a good excuse that they can't just bust out with the insta-wall every single encounter.... remember a brilliant idea can turn stale if filled w/ awesome.