Night Vision LDI options

[Spot-on]

I see on tnvc there are several LDI IR laser options for civvies:

1. DBAL - slaved visible and IR lasers
2. ITAL - inline IR laser only
3. OTAL - offset IR laser only

I think I understand the difference between them as listed above, but what I need guidance on is which model and mounting options are working out well for people? Is it ITAL mounted at 3 or 9 o'clock, or offset mounted at 12, or ??? (I understand about the front sight potentially getting in the way of some mountings. Are the DBAL lasers both offset a little so a 12:00 mounting would let each one bypass the front sight on each side?)

Next, any neat tricks for zeroing the ITAL or OTAL (with no visible laser to work from)? Or is it just go out to the range at night? (I'm assuming daylight would wash out the IR and you wouldn't be able to see the aiming point during the day.)

Finally, I noticed in the tnvc descriptions that the DBAL has a range of 200 yards, the ITAL 450, and the OTAL 400 yards. Yet they all seem to use the same 0.7mW emitter. So why the difference?

Thanks for any recommendations.

 

[aubie515]

You need to be more specific because there are multiple DBALs...The DBAL I2 is not slaved and does not have an illuminator. The DBAL D2 is slaved and has illuminator.

I'm sure someone from TNVC will come along to answer your question and others who have used those items you listed.

 

[Spot-on]

I wasn't aware of that.

 

[JohnnyC]

By design, the lasers are supposed to be mounted on the top rail, all of them. The OTAL (and really all offset lasers) exists because people run a fixed front sight post, which obviously will not work with an ITAL. Ideally you want the laser in-line with the bore rather than offset if at all possible. If you don't have a front sight post in the way, the ITAL is the way to go for a simple IR-only laser.

With an offset laser the goal is to zero it perfectly parallel to the bore so that there's no crossover between the point of aim and point of impact. That's why the military has special laser zeroing targets. What can happen, and is exaggerated the farther away from the boreline your laser is, your point of aim and point of impact are only the same at one given distance, and closer you'll have offset, and further away you'll have offset. By placing the laser in-line (ITAL) or parallel to the bore (OTAL or other offset) you only have to account for an elevation offset, although with an offset laser you just have to remember that POI will be x distance in whatever direction you've mounted your laser.

Ok, now that the hypothetical is all out of the way......realistically you won't be engaging targets at a distance where the laser offset distance will really make a difference. Hell, I don't even know if you'd be able to get a laser zero'd that precisely or find a laser with small enough beam divergence that at that distance you'd be able to have that precise a beam to begin with. So, what most people do is pick a laser and pick some intermediate distance that's most likely going to be your engagement distance. You zero your laser for that point and know that at shorter and longer distances you're pretty close. Close enough that it won't matter that they're not perfectly zero'd.

Pick whichever laser you want, if it's an offset, put it on the top, if it's an in-line like an ITAL, put it on the top unless you've got a front sight post or it won't clear your folding front site. Zero it for whatever distance you'll be expecting to take a shot. To zero the IR-only ones, put your NOD behind your scope and turn on your laser. Overlay the dot onto your crosshairs and it should be close enough to do what you want it to do. If it's a red dot on your gun, it will probably be close enough that you won't even have to shoot the gun and it'll be close enough for short-range work. If it's a scoped gun, you'll definitely want to put some rounds through it just to make sure that it's as close as you want it.

 

[Spot-on]

Good feedback, thanks. Anyone able to shed light (no pun intended) on my other questions?

 

[I^2 Technologies - Peter]

I see on tnvc there are several LDI IR laser options for civvies:

1. DBAL - slaved visible and IR lasers
2. ITAL - inline IR laser only
3. OTAL - offset IR laser only

I think I understand the difference between them as listed above, but what I need guidance on is which model and mounting options are working out well for people? Is it ITAL mounted at 3 or 9 o'clock, or offset mounted at 12, or ??? (I understand about the front sight potentially getting in the way of some mountings. Are the DBAL lasers both offset a little so a 12:00 mounting would let each one bypass the front sight on each side?)

Next, any neat tricks for zeroing the ITAL or OTAL (with no visible laser to work from)? Or is it just go out to the range at night? (I'm assuming daylight would wash out the IR and you wouldn't be able to see the aiming point during the day.)

Finally, I noticed in the tnvc descriptions that the DBAL has a range of 200 yards, the ITAL 450, and the OTAL 400 yards. Yet they all seem to use the same 0.7mW emitter. So why the difference?

Ok as was covered every laser mentioned except the ITAL has an off-set to get around the Front sight post. Like Johnny said, best on the 12 o'clock position, zeroed exactly as described.

I have no idea why the disparity in the two distances, as they are the exact same laser module. When my design group took the specs for the DBAL-D2 to LDI for manufacture (yes you read that right, the D2 is not an LDI design) we speced a .3 MR laser to get the dot as small and round as possible. LDI incorporated this laser through their entire product line.

Thanks for any recommendations.

There is one other laser not mentioned. If you have a standard triangular front sight base, there is the LDI AR2-A that is a single IR laser mounted at 12 o'clock over the bore forward of the FSB, and it takes up NO rail space. I am a fan of this laser where many are not.

AR-2A | Lasers & Illuminators (Laser Devices, Inc. | World-Class Lasers & Tactical Lights)

 

[Victor-TNVC]

Hi Spot-on. Thank you for the interests in our products.

Since a few of the topics have been covered, the ranges of our DBAL, ITAL and OTAL units are basically the same except for the visible laser ranges which are further at night. We also actually test each and every unit at night where environmental differences give us slight differences which we measure from effective ranges. If you look at each IR ranges, they are all pretty close.

Hope this helps and Happy Veterans Day!

Vic

 

[Spot-on]

Thanks everyone for the replies. So if I am understanding this right, ALL the models discussed have an "offset". Even the ITAL (inline) ones are offset vertically from the barrel's line of fire. I could in fact mount an ITAL at 9:00 and it would possibly be more offset than an OTAL at 3:00? Or maybe the offset would just have horizontal components and not vertical components?

Anyway, thanks Johnny for reeling me back into reality. I am getting the impression that under 400 yards (the effective range of most of these) the offset matters little to none, no matter if it is horizontal or vertical. This is going on a rifle with a Aimpoint T-1 2 moa. I will use a PVS-14 on my head when using the IR laser. So I'll probably ask Victor to supply the cheapest of these models as all will work well, unless someone can assure me that the DBAL at 12:00 behind the T-1 would "bracket" the T-1 on each side with IR laser and red laser and therefore allow both lasers as well as the T-1 dot to work.

I could also mount the T-1 behind the DBAL but not sure if the T-1's dot would "clear" the DBAL housing.

 

[JohnnyC]

EVERYTHING except the bullet has offset (well, until they invent bullets with lasers in them). The ITAL only has offset in the vertical component if mounted at 12 or 6. At 3 or 9 an ITAL would only have offset in the horizontal component. The DBAL models and OTAL will always have vertical AND horizontal offsets regardless of where you put them. If you mounted an ITAL at 3 or 9 it would probably have more horizontal offset than either the OTAL or the DBALs. Unless you have a front sight that blocks the laser, I don't know why you'd put the ITAL anywhere but 12 o'clock though. That's defeating the purpose of having it in-line.

I can't figure out why you'd want to put the laser behind the T-1. Am I missing something? Where would you put the laser and where would you put the T-1? Your T-1 should be on the receiver and the laser should be at the front of that handguard.

 

[elephantrider]

Thanks everyone for the replies. So if I am understanding this right, ALL the models discussed have an "offset". Even the ITAL (inline) ones are offset vertically from the barrel's line of fire.

Yes, that is correct.

I could in fact mount an ITAL at 9:00 and it would possibly be more offset than an OTAL at 3:00? Or maybe the offset would just have horizontal components and not vertical components?

Yes, and no depending on how you are mounting each one. Take a closer look at how each one mounts the laser emitter in relation to the bore axis. Mounting the ITAL at 3 or 9 o'clock will align the laser vertically with the bore, but offset it horizontally (not a good thing as it is very different from how your standard rifle sights/zero work). Mounting the ITAL at 12 o'clock will just give you the vert. offset/zero very similar to your daytime optic. Mounting the OTAL at 3'oclock will put the laser below the bore axis and offset to the right. Being below the bore is terrible as you might be able to get a 25 meter zero and who knows after that. Mounting the OTAL at 9 o'clock will put the laser offset left and slightly above the bore axis, which might be useable.

Anyway, thanks Johnny for reeling me back into reality. I am getting the impression that under 400 yards (the effective range of most of these) the offset matters little to none, no matter if it is horizontal or vertical.

The vertical offset is always going to present just like it is with your daytime optics (your daytime optic sits about 2.5" above your bore axis and is precisely zeroed at one distance). You want to achieve a similar vertical zero with your IR laser, only offset the same horizontal distance throughout the trajectory. In other words with the DBAL I2, DBAL D2, or OTAL mounted at 12 o'clock, only adjust the vertical not the horizontal. You want to keep the same horizontal mechanical offset at all ranges. This is called parallel zeros. You are using same trajectory as with your daytime optic but slightly offset. The ITAL at 12 o'clock is even easier as there is no horizontal offset.

This is going on a rifle with a Aimpoint T-1 2 moa. I will use a PVS-14 on my head when using the IR laser. So I'll probably ask Victor to supply the cheapest of these models as all will work well, unless someone can assure me that the DBAL at 12:00 behind the T-1 would "bracket" the T-1 on each side with IR laser and red laser and therefore allow both lasers as well as the T-1 dot to work.

I could also mount the T-1 behind the DBAL but not sure if the T-1's dot would "clear" the DBAL housing.

Not sure what you mean by putting the DBAL behind the T-1, but the DBAL should definitely go in front of the T-1, if not all the way forward on your rail. If you are referring to the DBAL I2, then when you mount it at 12 o'clock you will have the IR laser offset to the left (bullet will impact slightly to the right of the IR laser aiming point) and the visible laser offset to the right (bullet will impact slightly to the left of the visible laser aiming point). Each is offset in the opposite direction and zeroed independently on the DBAL I2. There, clear as mud.