Do lasers have recoil?

Why would it? Does a flashlight have recoil? (sorry if that sounds snarky...it's the best way I could think to give an explanation that was managable).

The problem is that while logically they shouldn't I can't find any specific rule saying they don't follow normal recoil rules.

Why should there be a rule? Common Sense prevails here.

I might even go so far as to give lasers an extra die for accuracy. There is something to be said for not having to bother to lead your target.

One would hope...
I actually wouldn't. Leading the target seems too natural for those who've fired guns that you could quite easily skew your shot by aiming for where they will be instead of where they really are.

I didn't take the quality .


I thought lasers had reduced DV for range as opposed to reduced pool to reflect that?

That's why lasers use the exotic weapon skill rather than the firearms skill. Seems a little harsh to me, but no matter how good you are at handling a pistol, it doesn't help you with an Ares Redline.

Personally, I always assumed lasers used the same rules for SA/BF/FA as any other weapon, since there's nothing in the rules that says they don't. I usually put it down to plasma blooming making the follow-up shots less accurate rather than any actual recoil in the weapon itself.

Out of curiosity I did a quick google search and came across a thread that could give a reasonable explanation to laser recoil
http://boards.straightdope.com/sdmb/showthread.php?t=418802

its not the beam from the laser that might throw off your aim but the magnetic field created by the power source interacting with the rest of the weapon.I think Its a good enough reason for gaming for why a laser would have 'recoil'

+1
You have your own Laserpointer with Your Laserweapon. Just squeeze the Trigger a bit and put the Laserbeam where the Laserbeam points at

with a Lazerdance
Medicineman

Probably a bit late, but I found the rules for recoil on lasers

"Laser weapons use highly concentrated beams of light to burn into and sometimes even through their targets. Laser weapons cause no recoil and are resisted with half Impact armor (rounded up)." page 41 of arsenal

Not late at all .

Nope. Too late. We've changed our games to include laser recoil. Let the arguments commence!

http://scienceblogs.com/builtonfacts/2010/...r-rifle-recoil/
http://thevirtuosi.blogspot.com/2010/04/to...stion-near.html

As long as you are okay with doing it wrong...

Like that's ever stopped an arguement on the internet before..

Just to throw some fuel somewhere beside the fire...

In my games, Lasers, etcetera, aren't exotic weapons. If you hold it and aim it like a pistol, a pistol it is. If you hold it and aim it like a rifle, a longarm it is. If you hold it and fire it like an automatic, an automatic it is.

Only things that truely fall outside of those "ways you pick up and use this" category get to be exotic weapons.

Wrong or Awesome?
Actually it has never come up in our games. As soon as someone sees the price of laser weapons (cash and karma for skill) they pick something else.

Recoil for Lasers is not Awesome.
Yes, they are somewhat expensive, but that makes no nevermind once you have established yourself.

I like to whip my enemies with the beam.

a little late to the conversation but just wanted to add in a few thoughts. substituting pistols/longarms/automatics for Exotic Weapon: Lasers could work, but I'd impose a -1 or -2 penalty, because lasers would be just different enough from a ballistic weapon (no leading the target, no compensating for drop, no recoil) that your muscle memory of handling a kinetic weapon wouldn't help you with a direct energy weapon. I like the idea of a +1 for Lasers, for their inherent accuracy, tho. I'd also allow a specialization in laser pistols/rifles, were I GM'ing.

the lasers presented in the 4th Edition Arsenal are all pulse lasers, meaning that the power is concentrated into a single 'bolt' of photons - this makes them significantly more powerful, but requires more energy. if you were using pulsed repeating lasers, I'd say that instead of recoil, that they would suffer from heat buildup, which would reduce the efficiency of the battery. a short 3 round burst would cost 4 shots worth of energy. a long 7 round burst would cost 10, a full 10 rounds costing 15 shots of energy. Botches during bursts can result in melting components and burnt hands.

other megas competing for the DEW market might try to make Continuous-Wave lasers, these are the more classic style of lasers that fire a continuous beam of energy. these don't require as much energy as a pulsed laser does, but they suffer from plasma blooming (as a laser vaporizes the material of the target it produces a cloud of gas that reduces the efficiency of the beam). CW Lasers would only be available as BF/Auto models, and the longer your burst, the greater reduction to the beam's effect. 3-rnd burst = +1 target's armor ((Impact Armor /2)+1); 7-rnd burst +3 armor; 10-rnd burst +5 armor. Due to their problems with plasma blooming, pulse weapons would be preferred by most militaries employing DE weapons.

Other options that could exist for lasers, are chemical lasers (Ares' weapons are all "hard" tech, relying purely on stored electrical energy), a tank filled with a specific chemical cocktail could be used as fuel for a laser. This has the disadvantage of needing to lug spare tanks and not being able to recharge the spent tanks. However, special mixes of fuel exist that could be used to increase the range of the laser (different fuel will change the wavelength of the laser, changing the distance at which it would start to lose power) or super-high efficiency fuel.

Mil Spec tech 2 features an Ares Pulse rifle that uses full auto with the base damage starting lower.

Quitters.

Indeed. One of my old characters had a katana with an underbarrel ares redline at chargen. (Thanks to the restricted gear and in debt qualities from Runner's Companion) The laser pistol was smartlinked and hooked up to an inertial trigger so that when it was armed (via the smartlink) it would automatically fire if the inertial trigger detected the impact of the blade hitting a target.

Thing was basically the melee-equivalent of a gauss rifle, it was awesome.

Well, the accuracy of laser weapons should be better espacially at long range.
I mean, it is quite a differance if you hit your target instantly or if you have your bullet travel for half a second being subject to wind and whatever.

IIRC, the idea was that diffraction through the air and other factors tended to make up for the shorter travel time and put lasers on about the same footing with conventional weapons as far as accuracy over a distance.

Diffusion. The concentrated heat of the laser ends up being absorbed by the air, reducing the effectiveness. Also, even though it is a concentrated beam, a laser will still broaden over a large distance - this is why you aren't supposed to shine laser pointers at airplanes; by the time the pinpoint laser reaches the cabin of the plane it actually fills the whole plane. Imagine the light emitting from the laser not so much as a tiny rod extending outwards but an extremely narrow cone.

That would be what's known as diffraction, omae--though you're right that heat diffusion can also be a problem.

Meh, I've been away from big words that don't have anything to do with chemicals for too long. Spent the last year or so doing hazmat stuff, so a bit rusty on the terms of other things.

If you were tossing around IDLH, LD50, molecular weight, vapor pressure, specific gravity, UEL/LEL, and solubility around I'd not have had such a brain fart. /shrug

This thread need some *SCIENCE*! (Insert mad cackle here)

...from Winchell Chung (Project Rho)...

http://www.projectrho.com/public_html/rock...dearmenergy.php
http://www.projectrho.com/public_html/rock...egunconvent.php

...Rick Robinson (Rocketpunk Manifesto)

http://www.rocketpunk-manifesto.com/2009/0...er-weapons.html

...and Luke Campbell:
http://panoptesv.com/SciFi/LaserDeathRay/DeathRay.html

Luke Campbell's stuff is the most relevant since he mainly focuses on atmospheric use sidearms instead space weaponry. He came up with three "categories" of laser weapons heat rays, blasters and ray beams:

Heat Ray:
"Heat Ray is the terminology I will be using for a laser that shines a beam of near constant power on its target for a prolonged period of time (from a few hundredths of a second or more). It causes damage primarily by heating the illuminated part of the target hot enough to cause softening, warping, blistering, cracking, charring, cooking, ignition, melting, or vaporization. Usually the heat ray heats up the surface of the target, but highly penetrating radiation (such as visible light on a transparent material or hard x-rays to most matter) can raise the temperature of a considerable volume along the beam path.

While heat rays can instantly scorch or ignite a surface, they generally require time to burn through the surface to vulnerable parts underneath. If the target can sense damage (such as our feeling of pain) and can writhe or turn away, the heat ray may be ineffective at reaching vital components or organs since it constantly has to burn through new parts of the surface. This drastically limits their use as antipersonnel weapons unless the beam is used as a sort of long range flamethrower, to ignite clothes and char the skin over a wide area. Against soft skinned, numb targets, the heat ray is more useful. In tests of modern heat rays against rockets in flight, the heat ray does not even have to burn through the skin, simply heating and softening the thin shell is sufficient to cause the rocket to blow itself to pieces."

Blaster:
"If a laser emits a pulse of light so intense that it causes matter it is incident upon to violently explode, I will call it a blaster. A single pulse can carve a crater out of the surface. If the pulse is fast enough and its energy is large enough, the subsequent blast can cause damage similar to that of the detonation of a high explosive. Alternately, the blaster can emit a very rapid burst of pulses, so fast that they land on top of each other. Each pulse enters into the hole dug out by its predecessors, allowing the blaster to drill deeply to reach vital components or organs.

It is likely that to acheive this performance, each pulse will have to be less than a nanosecond in duration. Some modern lasers can emit pulses that are picoseconds or femptoseconds in duration, so this is not a technological limit. The energy density of matter irradiated by these pulses can be higher than the fissioning core of an exploding nuclear weapon, or the fusioning core of a sun. This energy is so high that no matter held together by chemical bonds can withstand it. However, modern lasers deliver pulses that have an energy too low to cause much damage. They blast out only a very small amount of material - suitable for drilling small holes or producing a small flash of thermal x-rays but not for use as a weapon. To use a blaster for deep penetration against active targets, it is likely the pulses in a burst will need to be spaced only microseconds or less apart, and will all need to be delivered within a few milliseconds or less. "

Ray Beam:
"In brief: Ray beam weapons emit needle-thin beams that produce a white-hot plasma along their path and easily burn deep holes into their targets. They look and sound like bolts of straight lightning.

Detailed description: There are a wide variety of emmanations that can be broadly classed as "light", both invisible and visible. Lasers can be made to emit any of these. Those which are shorter wavelength, higher frequency, and higher energy per particle than the familiar visible light interact differently with matter than the more typical near ultraviolet, visible, and infrared electromagnetic emissions. The light in the vacuum ultraviolet, extreme ultraviolet, and soft x-ray region of the spectrum has unique properties that render death rays that use pulses of these wavelength significantly different from the effects of near visible blasters.

Air is transparent to the light of blasters, but the plasma the blaster pulse creates when incident upon condensed matter is opaque to their light. As a result, a thin layer of plasma absorbs all the light and then violently explodes. Ray beams have the opposite issue. They easily penetrate the energetic plasmas they create, allowing the beam to pass through and drill deeply. However, non-ionized matter of all kinds is essentially opaque to these radiations - including air. Consequently, the ray beam has to "burn" through air, ionizing it to a plasma state in order for the beam to penetrate.

A consequence of this is that the beam needs to be very narrow in order to avoid wasting a lot of energy burning through air between the laser and the target. However, as you will learn in the section on Diffraction, the narrower the beam, the faster it spreads out. Diffraction is less of an issue for these very short wavelength radiations, but it is still important for sub-millimeter wide beams if you want them to maintain focus over distances of tens or hundreds of meters.

In vacuum, these problems go away and the beam can be emitted from a wide aperture and focused to a point, just as for any heat ray or blaster. Because of their short wavelengths, ray beams can be focused more tightly from a given size aperture at any given range than near visible varieties of light. Thus if ray beams are technologically possible they are likely to be preferred for combat in space. "

Something that comes to mind that are not obvious at first glance is that lasers weapons have big optical parts, this means you're lugging around something that looks more like a big camera with a massive telephoto lens than a gun.

As it has been pointed out time and again, they're "hit-scan"... Using such a weapon is *lot* easier than any slug thrower. It was also (correctly) pointed out that all your muscle memory for kinetic weapons will work *against* you... but only on *follow up* shots.

How this is handled in game mechanics depends on how much of the old SR skill synergies you wanna bring back. Using the exotic weapon proficiency is the simplest approach, anything else will inevitably resemble older editions (SR1-3) somewhat.

I love rayguns. For a previous mad scientist character my GM allowed the Arc Pistol, a laser induced plasma channel weapon. It was 5S(e), -1/2 AP, and 10©. It could be switched to 5P 1/2AP for double the shot cost. I had a lot of fun with that gun.

Do you have to take separate Exotic Weps skills for each DEW or can you take Exotic Ranged Weapon: Directed Energy?

What damage did it do?

Nevermind.

( Strength / 2 + 8 )P, AP 1/2 -1

I managed to convince the GM to let me combine the damage codes, since both attacks were effectively hitting at the same time as part of the same weapon. At one point we tried going more by RAW and having it apply each of the damage codes separately, but honestly it was still pretty ridiculous. The fact that my character's strength was being maxed out by a combination of cyberware and combat drugs probably didn't help.

Holy carp! Meaty!!!

Slight turn on the topic, but back in Star Wars didn't you ever wonder about this?

Hey! Quit throwing physics into my space fantasy!

Now that would have been a clever plan to take down the second Death Star.

The solution I went with was to say that the sword was a nano-forged prototype with fiber optics running from the laser emitter in the hilt down into the blade. The ends of the fiber optic strands were placed at points along either side of the blade and aimed so that the beams would pass just over the surface of the metal and cross at just the right point for their wavelengths to cancel each other out via wave interference.

Since nanoforges are a thing and that's how laser weapons and fiber optics work in SR, the GM said OK. Technically, the inertial trigger was set up to activate the laser when it detected a swing, rather than detecting impact.

If you wanted to skip all that silliness and design one that could theoretically work in our universe all you'd need is a straight-bladed sword with a beam that fires parallel to it's edge, and rig the sensor so it doesn't fire the laser until the blade makes contact with a solid object. Of course, you'd probably end up damaging the blade from all that plasma being blown off the target when the laser hits.

Well, they were actually forcefields containing plasma, not an actual laser beam.

Indeed. And Shadowrun did have the Centurion Laser Ax in Cannon Companion, so there is a precedent set.

Indeed. And Shadowrun did have the Centurion Laser Ax in Cannon Companion, so there is a precedent set.

Now I have to work THIS into a fight sometime.

Not that particular reflector, but maybe some mirrors in a Stuffer Shack or something.

Makes sense, think of those big convex mirrors they use for security in convenience stores.
Imagine getting hired to knock over a Quick-E-Mart--seems like a total milk run--until you find out the owner is a crack shot with an ares redline and has spent thousands of hours practicing bank shots off the mirrors and fiber-optic surveillance network built into his store.

Take care with how the Johnson words that request.

"Knocking over" can be taken very, very literally, depending on the money involved.

Nobody expects the Spanish In Construction!!!

You should be flogged for that comment. Flogged badly...

I thought it was amusing, at least.


Anyway: Re: Milk Runs that turn unexpectedly difficult, any Shadowrunner should be very, very suspicious of "milk runs." If it was a milk run, they wouldn't be hiring Shadowrunners, they'd be hiring street bangers; Runners should be accordingly paranoid.