Emisar D4vn - Smallest 18650 Quad Thrower

[b8llzblue]

Vinh are you still planning on releasing the xpl vn version? I'd like more lumens and have a bit less throw than the xpg2 version

 

[ven]

This seems vastly overspecced.. Reports suggest the real candela is around 26kcd. This is also in line of what you get when you dedome.

Vinhs measurements are comparative to his own, so if you have a 30kcd light, one of his 40kcd lights will throw around 10kcd more if makes sense. There are far too many variables in others measurements .

It is certainly more focused and concentrated than the 219c version, kcd wise its hard to be exact. If a throwier version is wanted, something a little different than offered........the D4vn is defo worth a look imo.

 

[Sledgestone]

Not sure that I really understand what you mean, Ven..

But it is relatively easy to check if someone owns both the XP-L Hi and his version. If his really does 37kcd it would be a pretty big difference between the two.

Also I'm thinking about dedoming on of mine, so then I'll know for sure.

 

[ven]

I mean vinhs measurements can all be compared with his other lights as the same sphere/settings are used. I could measure one light at 20kcd, you could measure the same light on your equipment at 25kcd. With all vinhs measurements being taken with the same sphere, you can compare other vinh lights to each other.

In past, if anything vinhs measurements have been conservative. However i have no means of measuring, but so far over the years i can confidently compare one v54 to another v54.

Taking figures away, and going from what i see, the 219c version is more of a wall of light,hard to make the hot spot out at a little distance. The D4vn is very noticeable, there is a substantial difference in throw to my eyes out of these. I dont have the xpl HI version to compare. I would have thought vinh would have compared though, as he would have not bothered doing the xp-g2 PDT version if makes sense.

Not too sure on the latest D4vn, he might be doing tweaks to the optics still as well as hand selecting his xp-g2's for the PDT version.

 

[Capolini]

Another thing to consider from Professor TEEJ! Taken from this link,,post # 56 :naughty:

http://www.candlepowerforums.com/vb/showthread.php?403386-V54-Lumen-amp-Lux-Measurements/page2


Well, you can COMPARE them all you want, its the conclusions you'd draw that would be suspect if expecting too fine a differentiation between lights.

Just to RE-Clarify:

Just because they are measured at 7.5 meters DOESN'T mean they are comparable numbers, EXCEPT at 7.5 m.


The reason is, again, the distance required for the beam to fully form.

This is WHY the 1 m numbers are always low for example on a good thrower, and we back calculate TO 1 m equivalent....and measure at a longer distance.


So if Beam A is fully formed at 6 m, and Beam B is fully formed at 15 m, and BOTH are measured at 7.5 M and back calculated to 1 m (cd), then, Beam A's cd number might be accurate, and Beam B's cd number might be lower than it really is.


If both are measured at 7.5 m, and Beam A is fully formed at 10 M, and Beam B is fully formed at 15 M, BOTH cd will be lower than they really are, but NOT necessary by the same amount...or with one 33% less, etc.

The DEGREE of beam formation is NOT necessarily the same, as every beam has its own collimation formation pattern. So, you really CAN'T compare the cd of all of them at 7.5 M UNLESS they ALL form NO FARTHER AWAY THAN THAT.

Well, you can COMPARE them all you want, its the conclusions you'd draw that would be suspect if expecting too fine a differentiation between lights.

The problem is, you'd need to know the cd to know if the light was more, or less, likely to NEED more distance, and, ironically, that's what you're trying to find in the first place.

_____________________________________________________________________________________________________________________________________

 

[MAD777]

I have both the stock Nichia 219c and Vinh's XPG2 PDT mod. I've measured both on my cell phone lights meter, so can give only relative data.
The D4vn XPG2 measures exactly double the D4 Nichia 219c, center of beam at 17 meters.
The Nichia is noticeably brighter in ceiling bounce indoors, which makes sense.

 

[ven]

What i like about the D4vn, is the way the spill(flood) is channelled quite a lot more narrow. The beam is completely different and actually less distracting in certain applications. By that, using along walkways, i am not getting bounce back off everything to the sides of me .

Hard to explain, imagine a large tunnel you could drive a car through, this light will fire the light down it without it hitting the sides close by. Although a loss of lumens compared to the dome on or other LED's in this light, more light is punched out ahead compared to going into the wide spill.

In a room, i can contain the D4vn beam on one wall . The D4 simply lights up the wall ahead(not as intense) and walls at the side.

I am finding the more i use, the more i enjoy..................and i am using a lot

 

[elcidroyale]

I am new to all this. Can someone explain why the D4VN XPG2 version costs so much more than his other modded D4Vn? What is so special about that emitter?

 

[thedodgedud]

I am new to all this. Can someone explain why the D4VN XPG2 version costs so much more than his other modded D4Vn? What is so special about that emitter?

The factory version has dome on. Vinh dedomes them and picks the best tint emitters and uses those, so it's a process to get good ones. He also changes the board that the emitters are on, to rotate them to create a better shaped beam. This results in more throw, better tint, and a better beam pattern

 

[Sledgestone]

I have both the stock Nichia 219c and Vinh's XPG2 PDT mod. I've measured both on my cell phone lights meter, so can give only relative data.
The D4vn XPG2 measures exactly double the D4 Nichia 219c, center of beam at 17 meters.
The Nichia is noticeably brighter in ceiling bounce indoors, which makes sense.

As I thought then. That would make the candela on the vn ~25kcd.

 

[Sledgestone]

I see what you mean now. But I don't agree with you that his numbers are conservative.

I have one of his modded lights that according to his numbers should be much better than its stock form. However, it's in fact much worse.

I know that my meter shows true numbers. Because almost all my light is within 5% of the manufacturers specs.

 

[thedodgedud]

I see what you mean now. But I don't agree with you that his numbers are conservative.

I have one of his modded lights that according to his numbers should be much better than its stock form. However, it's in fact much worse.

I know that my meter shows true numbers. Because almost all my light is within 5% of the manufacturers specs.

What light and how is it worse?

 

[Sledgestone]

I bought

T25vn XHP50 SD 2*26650/18650
2,720 OTF lumen at Turn On
2,600 OTF lumen at 30 second
113K Max Lux

I measured it to 80kcd..

 

[ven]

Maybe its the distance it is measured from which causes the variable. No doubt some will be measured over, usually dedicated throwers tend to be under due to not being measured at a further distance(variable in the beams focus, be it 10m, 15m or 20m etc .)

 

[Sledgestone]

Nope, I measured it at several distances including the distance he does his measuring at.

 

[ven]

Dont know then!

 

[thedodgedud]

Let's get back to d4vn topic

 

[Sledgestone]

Yes, sorry for the derail!

 

[Newlumen]

I like d4 so much and I take it to work and show off.. nice light... It's beautiful and it's more beautiful when u take it outside.

 

[ven]

Me to NL :laughing: great minds and all that!