Got Lucky - Right Place at the Right Time

[ShortArc]

Here is a pic of the Lead Acid Bat pack it came with.

 

[BVH]

Now That's what I call HEAVY duty!

One thing I did not plan on in deciding to do this project, was that the MR has a full-time parasitic current draw of about 40 mAh. I found this out while finishing the electrical connections and observing a tiny spark when connecting the fuse. So, while it's not difficult to remove the setscrew and front end cap for charging, it will require an additional R&Rs for connection and disconnection of the electrical when using the light. The draw will empty the pack in 4 days.

While I did not think that the mod was all that practical, I thought it worth the effort considering I wanted some experience on the lathe and mill and that I have another MR that is stock. This one may go back to stock. But then again, I hardly use them so what's a few extra minutes going to cost?

 

[ShortArc]

WOW a 40mA draw. That is alot. Thank you for this discovery.

 

[Lips]

Very Cool. I'm jealous!


Bet soldiers would like setup over heavy backpack at times.

 

[stephan van straaten]

What do mean the lights are from south africa?

 

[BVH]

What do mean the lights are from south africa?

Night Vision Optics/Megaray: Somerset House I 11 York Street I Randburg I Johannesburg I 2194 I South Africa

 

[japudjuha]

BVH
In your first post you mentioned a portable 28v power supply.

Quote:
"What the heck – a new 80 Watt Maxabeam is $2,300 and I can run this light on my 28 Volt portable power supply so a working light would cost me about $1,850 with shipping."

May I ask about the specifics of this PS.
I am looking for any options that will work for powering a Q4559X application.

Thanks
James

 

[BVH]

PM sent.

 

[BVH]

A free MegaRay charger over on MarketPlace Giveaways.

 

[bshanahan14rulz]

Very nice of you, nice kits too

I did want to comment and say that tube looks awesome!

 

[holylight]

When I get my hands on these, my wife will use it it to knock my head.....

 

[The_Driver]

BVH's light with the mounted battery is definitely one of my dream lights!

Using the numbers posted on their website and in the manual (for the current MKII version) I calculated some stuff:
At max-focus (2°) it does 51lux at 200m distance. This means the luminous intensity is 3,187,500cd (a quarter of the Maxabeam, so half the range)
In a distance of 1000m it thus does 3.1875lux. According to the manual the hotspot has a diameter of 35m in this distance with max-focus. That equates to an area of 962m2​. So there are around 3066 lumens in the actual beam at 1000m distance (values in other distances will be very similar)! That's an extremely high value for a light with this much candela! Since the light also doesn't have any real spill it is probably best suited for actually seeing stuff in long distances.

The Maxabeam has a very deep reflector which limits the amount of light which is actually in the hotspot (a lot actually goes into the corona). There are probably less than 1000 lumens actually in the main hotspot. Thats a big difference!

I have used the Lemax LX-70 (standard head version). Because of the properties of the arc in the car HID bulbs only a very small hotspot actually has the stated luminous intensity. The corona is much, much larger (and still very bright), but it intensity is much lower. I think the Superpower probably has a very similar beam pattern (jut more focussed). This means that there is also probably less light in the actual hotspot compared to the Megaray even though the Lemax lights have much more lumens to work with.

EDIT2: Together with the Lemax/Xe-Vision lights the Megaray also has a much better flood mode compared to the Maxabeam. The former can be used with a diffusor while the Megaray can de-focus to 6° and all the way to 74° with an add-on lens. All of that with a uniform beam pattern. The Maxabeam has a big donut hole when defocussed, can be used with an add-on lens (probably to get rid of the donut hole), but really suffers from low total lumens output.

EDIT3: it's interesting though that Cermax states that the bulb used in the Mageary (Cermax PE175BF) only produces 2200lumens at 175W!?! In the manual Megaray states a lumens output of 4375 lumens "as per the lamp manufacturer at 25lm/W". The latter value does make much more sense to me! Low-powered xenon short-arc lamps have an efficiency in this range.

Edit4: my calculations are probably wrong. The Megaray also has a visible corona on BVH's beamshots. The stated spot diameter probably refers to this Corona. This beam profile makes sense because the arc of a Xenon short-arc bulb does not have a uniform luminance like an LED. It has a small bright spot and a dimmer, much larger area around it.