ROP NiMH vs ROP LIon beamshot

So curiousity got the better of me, and i popped out the low output bulb in my 2D ROP and put in the high one :devil: .

Two ROPS used

2D ROP
-UCL
-Low loss LOP reflector
-Modamag 6aa holder
-6xCBP 1650s hot off charger, series config
-Solder wicked spring caps
-Contact cleaned *every* possible contact point

3D ROP
-UCL
-Low loss LOP reflector (identical to one in 2D ROP)
-No battery holder
-4 18650 2200mAh LIons, rare earth magnets to connect cells together, 2 series 2 parallel config
-Solder wicked spring caps
-Contact cleaned *every* possible contact point

2D Left, 3D Right


That was my first time seeing my two different ROP setups side by side. Well 2D just got ate by the 3D =/. I knew when i finished building my 3D that there was some difference, but i didn't know there was *that* much difference =/. If my 2D setup is putting out near 800 lumens, my 3D will definitely be able to mix it no problems with 3D M@g85's. and i get 1 hour of relatively flat runtime, not to mention much lighter (weight).

Notice how Mr3D's hotspot is larger than 2D ? I don't know how because the lights were the same distance away. Also notice that the immediate sidespill of 3D is larger and brighter than 2D. You might even notice that the 3D's beam is MUCH whiter than the 2D...i used to think my 2D ROP's beam was white as can be (bar LEDs), obviously i was mistaken =/. I'm still kind of shocked by the comparison...

Oh yeah, general usage like lighting up trees/houses far away, i can definitely tell the difference between the 2D and 3D. I know my 2D isn't underperforming either, because when i turned it on by itself, it was definitely bright and looks brighter than when i first built it (I actually had higher resistance when i first built it and as i did various tweaks the colour and output improved. I've been through a few lamps as well...i like strobing them =P)

One last note, had the 3D had a new bulb in it, it would've ate the 2D even better. When i first installed the new low loss reflector in the 3D, the opening rubbed against the bulb when i used the cam action and the bulb actually has some reflector coating melted onto it which no doubt, would be eating some lumens.

thanks for the beamshots Delvance - nice work, I find that side by side shots are so useful. Interesting to see that the li ions are out doing the legendary CBP1650's.

Do you have a mag85? I'm pretty sure mine is a lot whiter than that - we can run them side by side if you want, we live in the same city.

Heya Missionaryman!

Thanks =). Yeah i was surprised how stomped the cbps got as well. Unfortunately, i don't have have a M@g 85. I'm considering building one though, after my current project. The photo doesn't do the whiteness justice, bear in mind the beam is shot against a brown/red coloured wall. I'll post a whitewall beamshot later if i get some time.

Would love to compare to a M@g85, would love to see a M@g 85 in action too mhmm.

missionaryman said:

thanks for the beamshots Delvance - nice work, I find that side by side shots are so useful. Interesting to see that the li ions are out doing the legendary CBP1650's.

Do you have a mag85? I'm pretty sure mine is a lot whiter than that - we can run them side by side if you want, we live in the same city.

Click to expand...

I wonder how much power each one of those setups is dissipating. Can you do a current test at the tailcap to give us a feel for current at least. Voltage would be great too but that is a bit harder.

BTW: THe CBS's still sag further than the sub-c's so I wonder how the original 4D ROP would do.

I wonder which bulb is "capable" of being brighter? I say this because it seems that the ROP bulb can take some serious abuse. Most people run the Mag85 on 9xAA's and pop the bulb if they dont let the batteries settle a bit off the charger. This means it is being run extremely close to the edge. THe ROP bulb doenst seem to care too much about the cells hot off the charger. This means that it isnt close to the edge. I have heard of some running the ROP bulb on 7 cells but have never seen it. It will be interesting to see what happens when the "dial a voltage" regulators hit the streets

The 7-high-current-cell crew have popped bulbs after a couple of runs. bwaites ran his with 7 x 1/2D cells and confirmed that there is an instaflash risk. I designed the ROP to be able to light hot off the charger on a six cell high-current NiMH pack. You'll note my original ROP has six high current Sub-Cs good for 20+ amps continous.

Your 2S2P lithium ion config is pretty cool.. as far as I know you are one of the first to implement it and your 3D is definitely taking less voltage sag than the 2D.

Current for incandescent bulbs should be equal. You will definitely want to measure voltage drop, a far more tricky operation. To do that, you'll have to insert your DMM probes between the positive and negative legs of the circuit in parallel with the circuit.. how you're going to do that, don't ask me, because I frankly have no idea (mechanically)....

One thing that I have been wondering for a while is how the NiCD version of the bulb would work if powered by 7 or 8 cells. Anyone ever done that?

Ginseng ran 7 cells against a WA1274 7.2V 2.77A.

I would think the Big D Nicad would be rated~3.33A to get to 24 watts.

I want to see how that puppy hunts in your big bad 8 banger.

Yah the 3D is definitely outperforming the 2D. I've measured current draw before and i'm prettyu sure it was around 4.1A (4.13 to be exact but i doubt my cheapie meter is that good). I'd love to measure the V at lamp sometime too but lack of time and laziness prevents this lol (got to wrap some wire around the 've etc and lead it out and turn light on in a safe shielded area).

Also curious how it'd compare to the 4D subC design! I have a feeling the 4D will outperform my 3D if quality subCs are being used.

Those 7.2V BigD bulbs are interesting...i think maybe one day i'll get some and experiment with them.

I'm not going to be using regulators in my lights (funds absorbed in current project), but if someone were to add a regulator in their ROP and have 8 cells...they'd be able to adjust the output to near 7 cells (at lamp)...now that would be very nice!