Laser Rifle Range??? Another Laser thread, but different

[bobharly]

So in the world of kinetic weapons, good old gravity pulls stuff down. Plus, there is a bit of air resistance to blame too. So when a M-16 has a range of 1500' it makes sense to me.

But when a laser has a range, let's say 1500' again, what happens at 1501'??? Gravity isn't a factor. Air resistance can't be much of a problem either, since we are still rolling full damage, right? Does it just abruptly dissipate? And what happens when the laser strikes natural surfaces like water in a lake or earth and rock? I had a nomad hiding behind a dirt mound, about 2' thick for cover. An another was behind a 18" thick adobe wall. I made judgement calls and allowed the blasts to penetrate both, absorbing 2/3rds the energy. But it would be nice to know how natural elements resist Laser strikes.

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

Thanks.

[Tiree]

Obviously utilize your best judgement, as this is a game.

But yes, I always go with the theory that Power, Diffusion, Etc... is the reason it does not go past the ranges dictated in the book. I do allow for extended ranges while in space. But please remember that gravity does affect light as well - so Lasers would be affected.

[bobharly]

Obviously utilize your best judgement, as this is a game.

But yes, I always go with the theory that Power, Diffusion, Etc... is the reason it does not go past the ranges dictated in the book. I do allow for extended ranges while in space. But please remember that gravity does affect light as well - so Lasers would be affected.

I know it's just a game. But some folks have really clever ideas to share, so why not ask?

And yes, light is affected by gravity, but not in the same way that a bullet is. So giving lasers similar ranges as bullets seems a bit odd to me when I think about it.

[Marcethus]

I use the idea that the stated range is the effective range of the weapon. After going out side of that range the accuracy for targeting becomes problematic. And if someone wanted to target out of effective range then well penalties apply.

[bobharly]

I use the idea that the stated range is the effective range of the weapon. After going out side of that range the accuracy for targeting becomes problematic. And if someone wanted to target out of effective range then well penalties apply.

For game play, I agree.

I was feeling philosophical. I mean we read in the news of airplanes being annoyed by people with laser pointers or laser Christmas lights from up to 8 miles away! But a laser rifle is only good for 2000'??? I know the technology is totally fictionalized for the game play, but it does raise a valid question?

[Marcethus]

yes it does. One I have often pondered myself. But I am too lazy to try and rewrite the game rules to reflect reality unless they totally need it. Which in this case doesn't feel as if it does.

[Axelmania]

Past the range you just get strike penalties.

[Svartalf]

With lasers, the damage would also be affected as the ray starts to lose coherence due to refraction from humidity and dust in the atmosphere.

[VictoryWeaver]

Diffusion of the beam.

[ShadowLogan]

So in the world of kinetic weapons, good old gravity pulls stuff down. Plus, there is a bit of air resistance to blame too. So when a M-16 has a range of 1500' it makes sense to me.

But when a laser has a range, let's say 1500' again, what happens at 1501'??? Gravity isn't a factor. Air resistance can't be much of a problem either, since we are still rolling full damage, right? Does it just abruptly dissipate? And what happens when the laser strikes natural surfaces like water in a lake or earth and rock? I had a nomad hiding behind a dirt mound, about 2' thick for cover. An another was behind a 18" thick adobe wall. I made judgement calls and allowed the blasts to penetrate both, absorbing 2/3rds the energy. But it would be nice to know how natural elements resist Laser strikes.

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

I go with the range stat being the "effective" range of the weapon the beam will keep going after that, but as the beam travels farther out the beam will spreadout and get bigger so it will lose energy on target and at some point won't be able to do any real damage because of this and there will be some energy transfer to the air.

Its really a judgement call in how much of a given material will stop a solid/energy projectile from game purposes. Natural materials though will take full damage, but collectively they could act as a shield. It isn't in RUE any more (that I could find, could be wrong at a quick glance), but some of the older Main Books (Rifts Main Book included, it is on pg36) had a basic table for SDC items. It wasn't complete/extensive, but could help. You might also want to consider looking up rock/earth creatures for an idea of how much SDC/MDC they might have (even if it is magical, supernatural, or natural) as it could help gauge durability, and don't forget there are magical walls made of various substances that could also help (ex clay, stone, iron, ice) and maybe fortification information (I seem to recall some in Merc Ops).

[HWalsh]

So in the world of kinetic weapons, good old gravity pulls stuff down. Plus, there is a bit of air resistance to blame too. So when a M-16 has a range of 1500' it makes sense to me.

But when a laser has a range, let's say 1500' again, what happens at 1501'??? Gravity isn't a factor. Air resistance can't be much of a problem either, since we are still rolling full damage, right? Does it just abruptly dissipate? And what happens when the laser strikes natural surfaces like water in a lake or earth and rock? I had a nomad hiding behind a dirt mound, about 2' thick for cover. An another was behind a 18" thick adobe wall. I made judgement calls and allowed the blasts to penetrate both, absorbing 2/3rds the energy. But it would be nice to know how natural elements resist Laser strikes.

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

Thanks.

Lasers lose coherency for a number of reasons. They are varied and range from atmospheric particles effectively getting in the way to wavelength interference. To dig up some sources for you I found a wide breadth of articles on Google that went into far more detail.

http://www.photonics.com/EDU/Handbook.aspx?AID=25161

As to your rules question regarding the sand dune...

"Note that most blasts and beams stop upon hitting their target, and if a beam goes all the way through an SDC structure, it stops upon hitting whatever is behind the first target. The same is true of M.D. projectiles such as rail gun rounds."

Found in the first paragraph after the warning paragraph explaining, "How M.D. Weapons Work."

So, if they're hiding behind an M.D.C. dune, the blast hits the dune, damages or destroys the dune, and the guy behind it is unharmed.

If they're hiding behind an S.D.C. dune, the blast hits the dune, if it exceeds the S.D.C. of the dune it travels through and strikes the guy behind it.

[glitterboy2098]

RUE has rules for firing at targets beyond the listed ranges. It makes the shot harder but it is doable. The only issue is that it is presented as a flat percent beyond, rather than brackets to allow even longer shots, but that is easy to houserule

[bobharly]

an M.D.C. dune.

Ha! LOL. "I'm sorry but that sand dune was armor plated. It has MDC!"

Points taken and thanks for the reading material!

For everyone posting, I am familiar with the Range rules for the game and the old SDC lists from 1st edition (as that is what I play). I am not planning on rewriting the rules (I've already written too many house rules). I was just feeling curious as to how laser weapons would really work...

[dragonfett]

So in the world of kinetic weapons, good old gravity pulls stuff down. Plus, there is a bit of air resistance to blame too. So when a M-16 has a range of 1500' it makes sense to me.

But when a laser has a range, let's say 1500' again, what happens at 1501'??? Gravity isn't a factor. Air resistance can't be much of a problem either, since we are still rolling full damage, right? Does it just abruptly dissipate? And what happens when the laser strikes natural surfaces like water in a lake or earth and rock? I had a nomad hiding behind a dirt mound, about 2' thick for cover. An another was behind a 18" thick adobe wall. I made judgement calls and allowed the blasts to penetrate both, absorbing 2/3rds the energy. But it would be nice to know how natural elements resist Laser strikes.

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

Thanks.

Lasers lose coherency for a number of reasons. They are varied and range from atmospheric particles effectively getting in the way to wavelength interference. To dig up some sources for you I found a wide breadth of articles on Google that went into far more detail.

http://www.photonics.com/EDU/Handbook.aspx?AID=25161

As to your rules question regarding the sand dune...

"Note that most blasts and beams stop upon hitting their target, and if a beam goes all the way through an SDC structure, it stops upon hitting whatever is behind the first target. The same is true of M.D. projectiles such as rail gun rounds."

Found in the first paragraph after the warning paragraph explaining, "How M.D. Weapons Work."

So, if they're hiding behind an M.D.C. dune, the blast hits the dune, damages or destroys the dune, and the guy behind it is unharmed.

If they're hiding behind an S.D.C. dune, the blast hits the dune, if it exceeds the S.D.C. of the dune it travels through and strikes the guy behind it.

But the guy hiding behind a 2' mound will now ask "How much S/MDC does the earth have?"

Personally I would say that the earth mound that the guy was using to hide behind takes the entire blast but also vanishes in a show of dust, dirt, and debris.

My biggest issue is how there is no difference in hitting a target at 20' vs. 200' vs. 2000'. I feel that there should be some sort of penalty for targets based on how far they are and power armor and robot vehicles have targeting computers to help offset the penalties.

[Marcethus]

So in the world of kinetic weapons, good old gravity pulls stuff down. Plus, there is a bit of air resistance to blame too. So when a M-16 has a range of 1500' it makes sense to me.

But when a laser has a range, let's say 1500' again, what happens at 1501'??? Gravity isn't a factor. Air resistance can't be much of a problem either, since we are still rolling full damage, right? Does it just abruptly dissipate? And what happens when the laser strikes natural surfaces like water in a lake or earth and rock? I had a nomad hiding behind a dirt mound, about 2' thick for cover. An another was behind a 18" thick adobe wall. I made judgement calls and allowed the blasts to penetrate both, absorbing 2/3rds the energy. But it would be nice to know how natural elements resist Laser strikes.

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

Thanks.

Lasers lose coherency for a number of reasons. They are varied and range from atmospheric particles effectively getting in the way to wavelength interference. To dig up some sources for you I found a wide breadth of articles on Google that went into far more detail.

http://www.photonics.com/EDU/Handbook.aspx?AID=25161

As to your rules question regarding the sand dune...

"Note that most blasts and beams stop upon hitting their target, and if a beam goes all the way through an SDC structure, it stops upon hitting whatever is behind the first target. The same is true of M.D. projectiles such as rail gun rounds."

Found in the first paragraph after the warning paragraph explaining, "How M.D. Weapons Work."

So, if they're hiding behind an M.D.C. dune, the blast hits the dune, damages or destroys the dune, and the guy behind it is unharmed.

If they're hiding behind an S.D.C. dune, the blast hits the dune, if it exceeds the S.D.C. of the dune it travels through and strikes the guy behind it.

But the guy hiding behind a 2' mound will now ask "How much S/MDC does the earth have?"

Personally I would say that the earth mound that the guy was using to hide behind takes the entire blast but also vanishes in a show of dust, dirt, and debris.

My biggest issue is how there is no difference in hitting a target at 20' vs. 200' vs. 2000'. I feel that there should be some sort of penalty for targets based on how far they are and power armor and robot vehicles have targeting computers to help offset the penalties.

I too have had that issue for years, still haven't come up with a decent solution for it.

[HWalsh]

an M.D.C. dune.

Ha! LOL. "I'm sorry but that sand dune was armor plated. It has MDC!"

Points taken and thanks for the reading material!

For everyone posting, I am familiar with the Range rules for the game and the old SDC lists from 1st edition (as that is what I play). I am not planning on rewriting the rules (I've already written too many house rules). I was just feeling curious as to how laser weapons would really work...

Just to note, there are ways to get MDC environments. It's probably rare, but can happen.

[Killer Cyborg]

RUE has rules for firing at targets beyond the listed ranges. It makes the shot harder but it is doable. The only issue is that it is presented as a flat percent beyond, rather than brackets to allow even longer shots, but that is easy to houserule

Yup.
Just what I was going to say.

[bobharly]

My biggest issue is how there is no difference in hitting a target at 20' vs. 200' vs. 2000'. I feel that there should be some sort of penalty for targets based on how far they are and power armor and robot vehicles have targeting computers to help offset the penalties.

After reading the website link above, I think the key word here is "Diffraction", the idea that over longer distances the beam begins to break up as it passes through humidity, air and other elements between you and the target. Since Lasers travel like light, a penalty at range has more to do with how steady your aim is. Effective range may be the human element of hand-eye coordination. But this still leaves the question open for computer assisted targeting and professional snipers.

My take on diffraction is that as the beam fractures over distance it loses energy. Thus beyond the effective range it does less damage. But that requires new rules... Interestingly enough in 1st edition Robotech, Southern Cross, several Laser Pistols have two different damage settings. The Night Stalker for example does 2d4 MD up to 600' and 1d4 MD up to 1200'. I suspect this was an early attempt to address the issue, but was later abandoned for game simplicity.

[bobharly]

an M.D.C. dune.

Ha! LOL. "I'm sorry but that sand dune was armor plated. It has MDC!"

Points taken and thanks for the reading material!

For everyone posting, I am familiar with the Range rules for the game and the old SDC lists from 1st edition (as that is what I play). I am not planning on rewriting the rules (I've already written too many house rules). I was just feeling curious as to how laser weapons would really work...

Just to note, there are ways to get MDC environments. It's probably rare, but can happen.

Yes, as a GM I agree there are ways, but I was imagining the look on my player's face. I hope my humor doesn't translate too poorly over the internet.

[drewkitty ~..~]

So in the world of kinetic weapons, good old gravity pulls stuff down. Plus, there is a bit of air resistance to blame too. So when a M-16 has a range of 1500' it makes sense to me.

snip...

I will point out the unlike with most spells and other powers, the ranges given for mundane weapons are just their "Effective" range. The range within they are most effective. (no penalties when used with a WP).

Yes, RUE is short on text about what sort of penalties are imposed on the strike roll when shooting 'over-ranged'. In fact, off hand I can't think of any text in any of the books that deals with 'over-ranged' penalties. So most GMs make up their own.

---
Lasers….Theoretically if the laser weapon had a matched laser aiming pointer the weapon's range would be effectively Line of Sight for aiming concerns for smallarms. Damages….with MD lasers I would not impose any or much of penalty till 10 miles out, depending on the humidity and visibility index (rain, dust, other junk in the air) With SD lasers I would put the damage penalties starting around 5 miles.

---
With lasers there is also the refractional effects of the air, yes….that question a GM will have to answer themselves is will the refractional optic of the air bend the laser beam as it does normal light.

As in, if you can see the target behind the edge of the hill due to the refractional effects of the air, will the Laser be bent by the same effects of the air? (the mirage effect is caused by this refactional bending)

[glitterboy2098]

Yes, RUE is short on text about what sort of penalties are imposed on the strike roll when shooting 'over-ranged'. In fact, off hand I can't think of any text in any of the books that deals with 'over-ranged' penalties. So most GMs make up their own.

RUE pg 361, 2nd column, 6th paragraph

Out to 30% beyond the listed range, but at -5 to strike. Isnt hard to use that to houserule shots even farther away.

Ultimately, the main limiter is accuracy, be it due to human physical limits or those of mechanical aiming systems. The greater the distance, the bigger the effect otherwise minor imprecisions have on the relative aimpoint.

[drewkitty ~..~]

I am not a big fan of RUE. So I have not Brian'ed it.

[HWalsh]

:D I am not a big fan of RUE. So I have not Brian'ed it.

What don't you like about RUE?

[drewkitty ~..~]

:D I am not a big fan of RUE. So I have not Brian'ed it.

What don't you like about RUE?

Little things here and there.

Some that nerf a mages abilities and others that I find stupid or that (while making the game more realistic) downgrade the fun.

[Blue_Lion]

So in the world of kinetic weapons, good old gravity pulls stuff down. Plus, there is a bit of air resistance to blame too. So when a M-16 has a range of 1500' it makes sense to me.

But when a laser has a range, let's say 1500' again, what happens at 1501'??? Gravity isn't a factor. Air resistance can't be much of a problem either, since we are still rolling full damage, right? Does it just abruptly dissipate? And what happens when the laser strikes natural surfaces like water in a lake or earth and rock? I had a nomad hiding behind a dirt mound, about 2' thick for cover. An another was behind a 18" thick adobe wall. I made judgement calls and allowed the blasts to penetrate both, absorbing 2/3rds the energy. But it would be nice to know how natural elements resist Laser strikes.

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

Thanks.

Lasers lose coherency for a number of reasons. They are varied and range from atmospheric particles effectively getting in the way to wavelength interference. To dig up some sources for you I found a wide breadth of articles on Google that went into far more detail.

http://www.photonics.com/EDU/Handbook.aspx?AID=25161

As to your rules question regarding the sand dune...

"Note that most blasts and beams stop upon hitting their target, and if a beam goes all the way through an SDC structure, it stops upon hitting whatever is behind the first target. The same is true of M.D. projectiles such as rail gun rounds."

Found in the first paragraph after the warning paragraph explaining, "How M.D. Weapons Work."

So, if they're hiding behind an M.D.C. dune, the blast hits the dune, damages or destroys the dune, and the guy behind it is unharmed.

If they're hiding behind an S.D.C. dune, the blast hits the dune, if it exceeds the S.D.C. of the dune it travels through and strikes the guy behind it.

But the guy hiding behind a 2' mound will now ask "How much S/MDC does the earth have?"

Personally I would say that the earth mound that the guy was using to hide behind takes the entire blast but also vanishes in a show of dust, dirt, and debris.

My biggest issue is how there is no difference in hitting a target at 20' vs. 200' vs. 2000'. I feel that there should be some sort of penalty for targets based on how far they are and power armor and robot vehicles have targeting computers to help offset the penalties.

Dunes, sand bags and large rocks provide a level of protection against MD attacks. If I recall right Rifts mercenaries list them as having 1300 SDC for sand bags and rocks. A larger dune would of course have more protection. So a sand dune should provide MD protection.

[kaid]

Obviously utilize your best judgement, as this is a game.

But yes, I always go with the theory that Power, Diffusion, Etc... is the reason it does not go past the ranges dictated in the book. I do allow for extended ranges while in space. But please remember that gravity does affect light as well - so Lasers would be affected.

Basically its a matter of accuracy and diffusion. Enough atmospheric effects would blunt the impact of lasers over distance at least enough where they are no longer going to do MDC damage. Also a lot of the weapon distances are I think maximum accurate range not maximum possible range.

[J_cobbers]

My personal take on MD lasers in Rifts is that the technology when developed was designed with some sort of focal length such that at about or before the half way mark in the the range, the beam becomes perfectly focused and then inverted so that by the time it reached its normal range it was once again the same width as when it left the barrel, and further out from there it gets wider and less focused as it diffuses rapidly enough to dissipate the beam to the point where it won't do much if any damage (say beyond that extra 30% of the given range). Here's a poor man's ascii art depiction of what I mean:

Zap!:::===>-<====:::[-[-[-[

----^shot---^focal pt-^max ^laser dissipates

So basically because weapons makers know how dangerous MD laser weapons could be, the intentionally design them to rapidly lose focus as compared to modern conventional lasers.

[bobharly]

:D I am not a big fan of RUE. So I have not Brian'ed it.

What don't you like about RUE?

Drewkitty remembered my name! Cool.

I'm the kind of DM that writes my own rules when I am not satisfied with the book rules. Actually, I'm 1st edition, so that's RMB for me.

As for lasers, I have decided that the biggest limitation of the weapons is the Human holding them. As range increases to the max range, even a slight twitch or hesitation can compromise the shot. The energy blast likely continues beyond the range limit, as even the 1st edition rules allowed a -1 per 25' beyond. Just say that the other day, but don't have a page or book unless you need me to go find it again.

It makes sense that the laser blast continues on beyond the max effective range, but hitting something is more chance than aim or accuracy. Nat. 20 anyone?

[Axelmania]

With lasers, the damage would also be affected as the ray starts to lose coherence due to refraction from humidity and dust in the atmosphere.

In theory sure, but based on that there should probably be a similar difference in damage between 1000 feet and 4000 feet as there is between 4000 feet and 7000 feet. We would have to penalize damage within maximal range as well as beyond it.

I think this consideration may be valid for SDC lasers but not for MD ones. The fun part about MD is you can ignore petty stuff like the SDC of dust. It just can't reflect MD because MD laser is MEGA.

[kaid]

an M.D.C. dune.

Ha! LOL. "I'm sorry but that sand dune was armor plated. It has MDC!"

Points taken and thanks for the reading material!

For everyone posting, I am familiar with the Range rules for the game and the old SDC lists from 1st edition (as that is what I play). I am not planning on rewriting the rules (I've already written too many house rules). I was just feeling curious as to how laser weapons would really work...

I can imagine a situation like this and somebody just starts cursing about damn warlocks at it again.

[Natasha]

My personal take on MD lasers in Rifts is that the technology when developed was designed with some sort of focal length such that at about or before the half way mark in the the range, the beam becomes perfectly focused and then inverted so that by the time it reached its normal range it was once again the same width as when it left the barrel, and further out from there it gets wider and less focused as it diffuses rapidly enough to dissipate the beam to the point where it won't do much if any damage (say beyond that extra 30% of the given range). Here's a poor man's ascii art depiction of what I mean:

Zap!:::===>-<====:::[-[-[-[

----^shot---^focal pt-^max ^laser dissipates

So basically because weapons makers know how dangerous MD laser weapons could be, the intentionally design them to rapidly lose focus as compared to modern conventional lasers.

This is kind of close to the correct answer. Start at >-<; that is, cut off the first half and start from within the rifle (or very close to it). The beam width, w, as a function distance the beam travels, z, is

w(z) = w_i [ 1 + ( (λ z) / (π w_i^2) )^2 ]^0.5

where w_i is the minimum beam width and λ is the laser's wavelength. As long as z is less than or equal to

(π w_i^2) / λ

then w is essentially constant. This is the called the Raleigh range of the laser; when z is larger than the Raleigh range, then the beam width spreads in proportion to z.

However, when operated in atmosphere the effective range of the laser is going to be shorter. This is due to absorption and scattering of the laser. This is called attenuation. The rate of attenuation depends on the density of the atmosphere, the chemical composition of the atmosphere, and the wavelength of the laser light.

The damage done by a laser is related to the laser's energy density, which is Joules per meter squared. Spreading of the beam increases meter squared and diffraction reduces Joules. They combine to reduce the effective range because they reduce its energy density.

[Zer0 Kay]

So in the world of kinetic weapons, good old gravity pulls stuff down. Plus, there is a bit of air resistance to blame too. So when a M-16 has a range of 1500' it makes sense to me.

But when a laser has a range, let's say 1500' again, what happens at 1501'??? Gravity isn't a factor. Air resistance can't be much of a problem either, since we are still rolling full damage, right? Does it just abruptly dissipate? And what happens when the laser strikes natural surfaces like water in a lake or earth and rock? I had a nomad hiding behind a dirt mound, about 2' thick for cover. An another was behind a 18" thick adobe wall. I made judgement calls and allowed the blasts to penetrate both, absorbing 2/3rds the energy. But it would be nice to know how natural elements resist Laser strikes.

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

Thanks.

We'll considering the effective range for an M16 is 1803 feet for point and 2625 feet for area with a max range of 11811 feet (more than 2 miles), NOT a measly 1500 feet... what's your point? The game designers made up data. Heck they even call fast firing slug throwers that use a gauss field and require that the round be ferrous, railguns when railguns are normally slower loading and use Lorentz forces to drive a conductive armature down the rails either being a part of the round or pushing it. They made ion weapons short range, stronger energy weapons. There is no other reason to pick between energy weapons besides how far you plan to engage your opponent and how much damage you want to do. There are soooo many issues with the weapons that the range of the lasers isn't the largest issue.

Why a laser would do damage past a given range. Well first off bother the solid and energy projectiles should diminish in damage with range as energy is being lost. So we know that it isn't accounted for with bullets so why would it be with lasers? As a laser travels it will diffuse, the photon beam becoming less cohesive and in Palladium, without the use of extended range or house rules the bullet stops and falls to the ground (otherwise the shooter would just have to aim higher) the Laser, particle beam, ion blast and plasma beam, ball or whatever you use just fizzles out. The range is just the farthest point of damage the light continues on it just no longer causes damage. For realism you could always use RL ranges for weapons with diminishing damage and come up with something for energy weapons.

[ShadowLogan]

So in the world of kinetic weapons, good old gravity pulls stuff down. Plus, there is a bit of air resistance to blame too. So when a M-16 has a range of 1500' it makes sense to me.

But when a laser has a range, let's say 1500' again, what happens at 1501'??? Gravity isn't a factor. Air resistance can't be much of a problem either, since we are still rolling full damage, right? Does it just abruptly dissipate? And what happens when the laser strikes natural surfaces like water in a lake or earth and rock? I had a nomad hiding behind a dirt mound, about 2' thick for cover. An another was behind a 18" thick adobe wall. I made judgement calls and allowed the blasts to penetrate both, absorbing 2/3rds the energy. But it would be nice to know how natural elements resist Laser strikes.

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

Thanks.

We'll considering the effective range for an M16 is 1803 feet for point and 2625 feet for area with a max range of 11811 feet (more than 2 miles), NOT a measly 1500 feet... what's your point? The game designers made up data. Heck they even call fast firing slug throwers that use a gauss field and require that the round be ferrous, railguns when railguns are normally slower loading and use Lorentz forces to drive a conductive armature down the rails either being a part of the round or pushing it. They made ion weapons short range, stronger energy weapons. There is no other reason to pick between energy weapons besides how far you plan to engage your opponent and how much damage you want to do. There are soooo many issues with the weapons that the range of the lasers isn't the largest issue.

Why a laser would do damage past a given range. Well first off bother the solid and energy projectiles should diminish in damage with range as energy is being lost. So we know that it isn't accounted for with bullets so why would it be with lasers? As a laser travels it will diffuse, the photon beam becoming less cohesive and in Palladium, without the use of extended range or house rules the bullet stops and falls to the ground (otherwise the shooter would just have to aim higher) the Laser, particle beam, ion blast and plasma beam, ball or whatever you use just fizzles out. The range is just the farthest point of damage the light continues on it just no longer causes damage. For realism you could always use RL ranges for weapons with diminishing damage and come up with something for energy weapons.

And the M16 I don't think is the only example of a real world weapon system that "falls into the WTH" category or don't get X type of system correct.

However, I will add that Palladium in the FIRST EDITION Robotech books (specifically Bk #4 and Sentinels reprinted those specifically) had several laser weapons that modified their damage based on range. That is an isolated incident AFAIK, and I don't dispute what you are saying, I am merely stating that Palladium has had rare examples like this in their publishing history.

This is ignoring that weapons are generically modified by firing in vacuum/underwater/atmosphere, but does nothing to the damage factor that is much more wide spread.

[Zer0 Kay]

With lasers, the damage would also be affected as the ray starts to lose coherence due to refraction from humidity and dust in the atmosphere.

In theory sure, but based on that there should probably be a similar difference in damage between 1000 feet and 4000 feet as there is between 4000 feet and 7000 feet. We would have to penalize damage within maximal range as well as beyond it.

I think this consideration may be valid for SDC lasers but not for MD ones. The fun part about MD is you can ignore petty stuff like the SDC of dust. It just can't reflect MD because MD laser is MEGA.

Yup that's why the SDC earth stopped the rain of death from the Zentradi fleet...

Regardless of particles being SDC or MDC it will effect the path and disrupt the photon that hit it. Damage Wethersfield it be normal mega or gigga will transfer it's energy, in part or whole into any matter it hits.

[Zer0 Kay]

So in the world of kinetic weapons, good old gravity pulls stuff down. Plus, there is a bit of air resistance to blame too. So when a M-16 has a range of 1500' it makes sense to me.

But when a laser has a range, let's say 1500' again, what happens at 1501'??? Gravity isn't a factor. Air resistance can't be much of a problem either, since we are still rolling full damage, right? Does it just abruptly dissipate? And what happens when the laser strikes natural surfaces like water in a lake or earth and rock? I had a nomad hiding behind a dirt mound, about 2' thick for cover. An another was behind a 18" thick adobe wall. I made judgement calls and allowed the blasts to penetrate both, absorbing 2/3rds the energy. But it would be nice to know how natural elements resist Laser strikes.

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

Thanks.

We'll considering the effective range for an M16 is 1803 feet for point and 2625 feet for area with a max range of 11811 feet (more than 2 miles), NOT a measly 1500 feet... what's your point? The game designers made up data. Heck they even call fast firing slug throwers that use a gauss field and require that the round be ferrous, railguns when railguns are normally slower loading and use Lorentz forces to drive a conductive armature down the rails either being a part of the round or pushing it. They made ion weapons short range, stronger energy weapons. There is no other reason to pick between energy weapons besides how far you plan to engage your opponent and how much damage you want to do. There are soooo many issues with the weapons that the range of the lasers isn't the largest issue.

Why a laser would do damage past a given range. Well first off bother the solid and energy projectiles should diminish in damage with range as energy is being lost. So we know that it isn't accounted for with bullets so why would it be with lasers? As a laser travels it will diffuse, the photon beam becoming less cohesive and in Palladium, without the use of extended range or house rules the bullet stops and falls to the ground (otherwise the shooter would just have to aim higher) the Laser, particle beam, ion blast and plasma beam, ball or whatever you use just fizzles out. The range is just the farthest point of damage the light continues on it just no longer causes damage. For realism you could always use RL ranges for weapons with diminishing damage and come up with something for energy weapons.

And the M16 I don't think is the only example of a real world weapon system that "falls into the WTH" category or don't get X type of system correct.

However, I will add that Palladium in the FIRST EDITION Robotech books (specifically Bk #4 and Sentinels reprinted those specifically) had several laser weapons that modified their damage based on range. That is an isolated incident AFAIK, and I don't dispute what you are saying, I am merely stating that Palladium has had rare examples like this in their publishing history.

This is ignoring that weapons are generically modified by firing in vacuum/underwater/atmosphere, but does nothing to the damage factor that is much more wide spread.

I'm pretty certain the m16 isn't. I just used it because it was in the OPEN.

Just like they used to have a particle beam IIRC the original was in Mechanics but migrated to BTS where the beam scattered and on almost misses they did less damage because the periphery instead of the core of the beam hit the target.

You say nothing that is not true.

I miss the days when they tried to be interesting with their weapons capabilities.

[Axelmania]

Yup that's why the SDC earth stopped the rain of death from the Zentradi fleet...

A dirt wall alone has hundreds of SDC (check Control Elemental Force Earth in HU) so could soak up MD, obviously a whole planet of it could soak up even more.

The cumulative weight of dust particules that a narrow laser beam would interact with over less than a mile doesn't seem like anything I'd assign any serious SDC to.

[bobharly]

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

Thanks.

We'll considering the effective range for an M16 is 1803 feet for point and 2625 feet for area with a max range of 11811 feet (more than 2 miles), NOT a measly 1500 feet... what's your point? The game designers made up data.

I pulled 1500' off the top of my head, because I recalled the Palladium books publishing a rather short range for the weapon. I am sorry being imprecise. So yes, when Palladium quotes an M16A1 as Effective Range of "1200 Feet" Robotech: Macross 1st Edition Reprint 1989, page 77 that #1 the writers are making stuff up and that #2 that represents Point Blank usage (Without accounting for elevation or wind), I understand that. And I also understand why a Sniper can use that same rifle up to 1/2 mile range under ideal circumstances. And I understand that the bullet is dangerous over 2 miles away. I understand all of that. That was not my point.

My point was that I did not understand is how Lasers work. And from all of the wonderful posts on this thread I have learned A LOT!!!

Furthermore, I agree that the one of the short comings of the game, amongst many for those of us who dare to question the realism, is that as range increases the amount of energy transferred should be reduced. However, I am not in the mood to rewrite those rules. I was simply curious and I have enjoyed everyone's input. Thank you for everyone who has contributed.

[Axelmania]

Writers are okay to make stuff up since Macross' M16A1 may work differently than the gun named that in our dimension.

Like how Palladium's dolphins are explicitly different inherently than ours.

[Natasha]

In any case, the bullet does not stop and fall to the ground. It starts falling to the ground the instant it leaves the barrel of the gun. The greatest range possible for any given muzzle velocity is when the projectile is shot 45 degrees from the horizontal. All other angles will give ranges less than the range at 45 degrees. In fact, complimentary angles like 30 degrees and 60 degrees give precisely the same range. Air resistance will cause shorter ranges at any angle because of the decreased velocity but where there is no atmosphere the muzzle velocity is the impact velocity; furthermore, such as on the Moon where gravity is much less than on Earth the exactly shot on the Moon as on Earth will travel a larger distance with no loss of energy.

You can say muscle shake for humans but not for cyborgs. So on and so forth. Pick a maximum range for the gun and pick an explanation... it's as good as any.

[J_cobbers]

My personal take on MD lasers in Rifts is that the technology when developed was designed with some sort of focal length such that at about or before the half way mark in the the range, the beam becomes perfectly focused and then inverted so that by the time it reached its normal range it was once again the same width as when it left the barrel, and further out from there it gets wider and less focused as it diffuses rapidly enough to dissipate the beam to the point where it won't do much if any damage (say beyond that extra 30% of the given range). Here's a poor man's ascii art depiction of what I mean:

Zap!:::===>-<====:::[-[-[-[

----^shot---^focal pt-^max ^laser dissipates

So basically because weapons makers know how dangerous MD laser weapons could be, the intentionally design them to rapidly lose focus as compared to modern conventional lasers.

This is kind of close to the correct answer. Start at >-<; that is, cut off the first half and start from within the rifle (or very close to it). The beam width, w, as a function distance the beam travels, z, is

w(z) = w_i [ 1 + ( (λ z) / (π w_i^2) )^2 ]^0.5

where w_i is the minimum beam width and λ is the laser's wavelength. As long as z is less than or equal to

(π w_i^2) / λ

then w is essentially constant. This is the called the Raleigh range of the laser; when z is larger than the Raleigh range, then the beam width spreads in proportion to z.

However, when operated in atmosphere the effective range of the laser is going to be shorter. This is due to absorption and scattering of the laser. This is called attenuation. The rate of attenuation depends on the density of the atmosphere, the chemical composition of the atmosphere, and the wavelength of the laser light.

The damage done by a laser is related to the laser's energy density, which is Joules per meter squared. Spreading of the beam increases meter squared and diffraction reduces Joules. They combine to reduce the effective range because they reduce its energy density.

Huzzah Science! I figured I would start at the point of emission, or final focusing lens as that would be the point at which what ever super science optical tricks would apply their effects on the beam. My whole concept is that an artificial "flaw" in the focal properties in the beam is introduced for safety (minimize collateral damage) and so on. Perhaps they also factored in atmospheric attenuation into the selection of wavelengths used in MD lasers for much the same reason.

Much like the CS and others generally don't use full sized city destroying nukes in their missiles, but rather use 'tactical nukes' I kind of see MD lasers in Rifts and other PB MD settings as "tactical lasers" designed for limited combat engagement ranges. Where as other possible uses for lasers in things like communications and the like wouldn't have these purposeful design characteristics.

[J_cobbers]

In any case, the bullet does not stop and fall to the ground. It starts falling to the ground the instant it leaves the barrel of the gun. The greatest range possible for any given muzzle velocity is when the projectile is shot 45 degrees from the horizontal. All other angles will give ranges less than the range at 45 degrees. In fact, complimentary angles like 30 degrees and 60 degrees give precisely the same range. Air resistance will cause shorter ranges at any angle because of the decreased velocity but where there is no atmosphere the muzzle velocity is the impact velocity; furthermore, such as on the Moon where gravity is much less than on Earth the exactly shot on the Moon as on Earth will travel a larger distance with no loss of energy.

You can say muscle shake for humans but not for cyborgs. So on and so forth. Pick a maximum range for the gun and pick an explanation... it's as good as any.

While cyborgs don't have muscle shake, they have mechanical vibration and hydrolic pressure fluctuation

[Blue_Lion]

In any case, the bullet does not stop and fall to the ground. It starts falling to the ground the instant it leaves the barrel of the gun. The greatest range possible for any given muzzle velocity is when the projectile is shot 45 degrees from the horizontal. All other angles will give ranges less than the range at 45 degrees. In fact, complimentary angles like 30 degrees and 60 degrees give precisely the same range. Air resistance will cause shorter ranges at any angle because of the decreased velocity but where there is no atmosphere the muzzle velocity is the impact velocity; furthermore, such as on the Moon where gravity is much less than on Earth the exactly shot on the Moon as on Earth will travel a larger distance with no loss of energy.

You can say muscle shake for humans but not for cyborgs. So on and so forth. Pick a maximum range for the gun and pick an explanation... it's as good as any.

While cyborgs don't have muscle shake, they have mechanical vibration and hydrolic pressure fluctuation

Eben Full conversion borgs breath that can cause changes in aiming point.

[Natasha]

My personal take on MD lasers in Rifts is that the technology when developed was designed with some sort of focal length such that at about or before the half way mark in the the range, the beam becomes perfectly focused and then inverted so that by the time it reached its normal range it was once again the same width as when it left the barrel, and further out from there it gets wider and less focused as it diffuses rapidly enough to dissipate the beam to the point where it won't do much if any damage (say beyond that extra 30% of the given range). Here's a poor man's ascii art depiction of what I mean:

Zap!:::===>-<====:::[-[-[-[

----^shot---^focal pt-^max ^laser dissipates

So basically because weapons makers know how dangerous MD laser weapons could be, the intentionally design them to rapidly lose focus as compared to modern conventional lasers.

This is kind of close to the correct answer. Start at >-<; that is, cut off the first half and start from within the rifle (or very close to it). The beam width, w, as a function distance the beam travels, z, is

w(z) = w_i [ 1 + ( (λ z) / (π w_i^2) )^2 ]^0.5

where w_i is the minimum beam width and λ is the laser's wavelength. As long as z is less than or equal to

(π w_i^2) / λ

then w is essentially constant. This is the called the Raleigh range of the laser; when z is larger than the Raleigh range, then the beam width spreads in proportion to z.

However, when operated in atmosphere the effective range of the laser is going to be shorter. This is due to absorption and scattering of the laser. This is called attenuation. The rate of attenuation depends on the density of the atmosphere, the chemical composition of the atmosphere, and the wavelength of the laser light.

The damage done by a laser is related to the laser's energy density, which is Joules per meter squared. Spreading of the beam increases meter squared and diffraction reduces Joules. They combine to reduce the effective range because they reduce its energy density.

Huzzah Science! I figured I would start at the point of emission, or final focusing lens as that would be the point at which what ever super science optical tricks would apply their effects on the beam. My whole concept is that an artificial "flaw" in the focal properties in the beam is introduced for safety (minimize collateral damage) and so on. Perhaps they also factored in atmospheric attenuation into the selection of wavelengths used in MD lasers for much the same reason.

Much like the CS and others generally don't use full sized city destroying nukes in their missiles, but rather use 'tactical nukes' I kind of see MD lasers in Rifts and other PB MD settings as "tactical lasers" designed for limited combat engagement ranges. Where as other possible uses for lasers in things like communications and the like wouldn't have these purposeful design characteristics.

You'd have a fluctuating energy density; it would be minimum at the end points and maximum at the midpoint. Then again, maybe that's why we have dice to roll for damage. The lens would be quite useful for things like the Wilks cutting tool. The focal point's diameter would be roughly the laser's wavelength and that'd jack up the energy density.

The Raleigh range is a quick way to determine the beam width required to damage up to the range: choose z and solve for initial beam width. For instance, a ruby laser has a wavelength of 0.69 micrometers; setting the max effective range to 1 kilometer yields a 1.5 centimeter beam. And from that the energy density can be calculated. Sometimes it is desirable to go on and calculate the electric field if for no other reason than to see why a 10 Joule ruby laser with a nanosecond pulse duration packs such a punch.

As about the cyborg, I reckon it depends on its power source and what components are moving when it's shooting.

[Zer0 Kay]

Please be educational. If you cite a rule from a palladium book, give the book and page. If you cite real science, you don't have to provide a supplemental link, but I would enjoy it if you did.

Thanks.

We'll considering the effective range for an M16 is 1803 feet for point and 2625 feet for area with a max range of 11811 feet (more than 2 miles), NOT a measly 1500 feet... what's your point? The game designers made up data.

I pulled 1500' off the top of my head, because I recalled the Palladium books publishing a rather short range for the weapon. I am sorry being imprecise. So yes, when Palladium quotes an M16A1 as Effective Range of "1200 Feet" Robotech: Macross 1st Edition Reprint 1989, page 77 that #1 the writers are making stuff up and that #2 that represents Point Blank usage (Without accounting for elevation or wind), I understand that. And I also understand why a Sniper can use that same rifle up to 1/2 mile range under ideal circumstances. And I understand that the bullet is dangerous over 2 miles away. I understand all of that. That was not my point.

My point was that I did not understand is how Lasers work. And from all of the wonderful posts on this thread I have learned A LOT!!!

Furthermore, I agree that the one of the short comings of the game, amongst many for those of us who dare to question the realism, is that as range increases the amount of energy transferred should be reduced. However, I am not in the mood to rewrite those rules. I was simply curious and I have enjoyed everyone's input. Thank you for everyone who has contributed.

I didn't know you were wrong with the 1500' I assumed it was pulled from the books.

[Zer0 Kay]

Yup that's why the SDC earth stopped the rain of death from the Zentradi fleet...

A dirt wall alone has hundreds of SDC (check Control Elemental Force Earth in HU) so could soak up MD, obviously a whole planet of it could soak up even more.

The cumulative weight of dust particules that a narrow laser beam would interact with over less than a mile doesn't seem like anything I'd assign any serious SDC to.

yup but regardless of it being only a few SDC it still is capable of deflecting MDC. Just like a car in the way of a train may derail the train. Of course the train may also just rip through the car but the train will be slowed even if slightly as some of the energy is transfered into the car.

[bobharly]

I didn't know you were wrong with the 1500' I assumed it was pulled from the books.

That's OK "Zer0 Kay". It just shows that my estimate was more generous than the publication. My estimate was based on real life experience from over 20 years ago with a .30-30 carbine (which by specs is also farther). I personally prefer point blank linear shots. I was never very good using adjustable elevation sites--I always had trouble gauge range by eye sight alone.

I write a lot of house rules, when I can reasonably apply them. However, in many cases this is only a game and in order to keep the game playable and fast paced I tried to avoid overly complex concepts. For example I might create a data sheet and change the damage of a weapon to reflect it's real world muzzle energy. But it is impractical to list out damage by range to show the loss of energy as blast goes from point blank to it's most extreme range. I am really enjoying the information from this thread, but as a GM I have already decided that it doesn't matter if the strike is at 5', 500' or 5000', we are just going to roll the same damage dice. Why? Because the dice already apply the randomness. I can create the drama of Point Blank damage through dramatic description of the damage inflicted (like I did last week) and it is more entertaining and fast than trying to make an overly specific rule. But... If a player has a question about how lasers work, I can now field that question and sound like I know a thing or two... And I can describe Laser strikes much better now too.

[J_cobbers]

You'd have a fluctuating energy density; it would be minimum at the end points and maximum at the midpoint. Then again, maybe that's why we have dice to roll for damage. The lens would be quite useful for things like the Wilks cutting tool. The focal point's diameter would be roughly the laser's wavelength and that'd jack up the energy density.

The Raleigh range is a quick way to determine the beam width required to damage up to the range: choose z and solve for initial beam width. For instance, a ruby laser has a wavelength of 0.69 micrometers; setting the max effective range to 1 kilometer yields a 1.5 centimeter beam. And from that the energy density can be calculated. Sometimes it is desirable to go on and calculate the electric field if for no other reason than to see why a 10 Joule ruby laser with a nanosecond pulse duration packs such a punch.

As about the cyborg, I reckon it depends on its power source and what components are moving when it's shooting.

I'm just gonna tip my nerd hat to you for the much greater understanding of the real world elements of lasers, their design and characteristics, but your explanation of energy densities based on the Raleigh formula actually kinda jives with my story based idea on laser ranges, not perfectly, but enough that if another player ever complained, I'd feel justified as using it as a semi-plausible explanation for how they work.

As for cyborgs, they are big walking talking machine bodies full of components that have to be monitored, and regulated. The power system is basically always on, and some sort of coolant is probably always being cycled through to regulate the power generation. Capacitors are being charged and discharged, motors are whirring (at the very least some sort of system is cycling blood through the few remaining organic organs), mechanical eyes are focusing, integrated computers are making calculations on and on. So like any complicated system, there are tons of factors that might affect the ability of the borg to focus on a target, plus if the darned thing is moving the borg will have to track with the target and that'll induce movement too. At least that'd be the kind of explanation I'd use for a justification on the limitations of a cyborg as the shooter rather than an equipment based one.

Also on a slightly related tangent, having shot M-16 and M4s as Service Member (and then just as a support MOS, not an infantry guy) being able to spot a target and put shot on it at 300 meters (~900 ft) during rifle qualifications (only so much time to shoot the target) without an optical enhancement is moderately difficult, unless you are out on the range to practice regularly. I imagine even with a laser weapon adding an additional 600 feet means the shooter would have to be very precise, something as simple as your breathing and how smoothly you pull the trigger can make a big difference and contribute to the maximum (effective) range our fictional laser guns.

[bobharly]

Also on a slightly related tangent, having shot M-16 and M4s as Service Member (and then just as a support MOS, not an infantry guy) being able to spot a target and put shot on it at 300 meters (~900 ft) during rifle qualifications (only so much time to shoot the target) without an optical enhancement is moderately difficult, unless you are out on the range to practice regularly. I imagine even with a laser weapon adding an additional 600 feet means the shooter would have to be very precise, something as simple as your breathing and how smoothly you pull the trigger can make a big difference and contribute to the maximum (effective) range our fictional laser guns.

Ah yes, the reality is much more difficult than the game. Thanks for sharing your personal experience. I never could match my dad, who was an army vet. But the game is "fiction" which is what I always remind myself when I start to take things to serious. We need a little bit of fantastic icing on our plausible cake!

[bobharly]

I was looking up how far a person can see under ideal circumstances and I found this. I never thought about the curvature of the earth, even on a relatively flat plane (like water or the Bonneville salt flats). Obviously, everything from slight elevation changes of surface to the humidity in the air would likely reduce line of sight to less than 3 miles, but I'd say that without radar and computer targeting, 3 miles is absolute max for line of sight on a flat surface.


"The Earth's surface curves out of sight at a distance of 3.1 miles, or 5 kilometers. But our visual acuity extends far beyond the horizon. If Earth were flat, or if you were standing atop a mountain surveying a larger-than-usual patch of the planet, you could perceive bright lights hundreds of miles distant.May 7, 2012



How Far Can the Human Eye See? | Human Visual Acuity - Live Science



www.livescience.com/33895-human-eye.html"

[dragonfett]

I was looking up how far a person can see under ideal circumstances and I found this. I never thought about the curvature of the earth, even on a relatively flat plane (like water or the Bonneville salt flats). Obviously, everything from slight elevation changes of surface to the humidity in the air would likely reduce line of sight to less than 3 miles, but I'd say that without radar and computer targeting, 3 miles is absolute max for line of sight on a flat surface.


"The Earth's surface curves out of sight at a distance of 3.1 miles, or 5 kilometers. But our visual acuity extends far beyond the horizon. If Earth were flat, or if you were standing atop a mountain surveying a larger-than-usual patch of the planet, you could perceive bright lights hundreds of miles distant.May 7, 2012



How Far Can the Human Eye See? | Human Visual Acuity - Live Science



http://www.livescience.com/33895-human-eye.html"

Now the more important question, what should the range be for an easy shot, medium difficulty shot, a tough shot, and an expert level shot?