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Torch Tests: New 'Nemo' vs Convoy S2+ Nichia


Cadmium

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The new 'no name', AKA 'Nemo' torch, introduced here first by Ulf:

https://www.ultravio...dpost__p__37933

 

Does anyone know the actual LED used in the 'Nemo' torch?

 

Here are some comparisons I did between the Nemo and Convoy S2+ Nichia torches.

All things being equal, with fully charged batteries.

 

Beam comparison. Distance is 3.75" (95mm). Reflectors in place.

post-87-0-46205100-1597636775.jpg

 

BLAK-RAY UV Meter test, distance is 3" (76mm), no filter. Reflectors in place.

post-87-0-07398700-1597636791.jpg

 

BLAK-RAY UV Meter test, distance is 3" (76mm), with Hoya U-340 2mm filter. Reflectors in place.

post-87-0-44248300-1597637776.jpg

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I'm trying to make sense of the results and failing. The Nemo is noticeably brighter, but the meter seems to give the same reading as the Convoy. Is it the same power but just a different amount of beam spreading?
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At what point is the Nemo brighter?

 

The outer diameter of the two beams look the same size from the same distance.

The center hot spot of the Convoy beam looks a little brighter than the brightest point of the Nemo.

Outer beams seem to have the same brightness.

The main difference I see is that the Nemo has a larger inner beam, thus a larger inner bright area.

 

If both torches are placed directly on the Meter they read the same brightness, about 8 (A scale).

The Meter sensor is rectangular, so not as deep (front to back) as wide. That may be part of the meter reading.

The actual beam photo is interesting to me.

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I'm trying to make sense of the results and failing. The Nemo is noticeably brighter, but the meter seems to give the same reading as the Convoy. Is it the same power but just a different amount of beam spreading?

I think the explanation is simple. The Nemo torch is brighter (it emits more light) but this light is spreaded over a wider area. The irradiance (W/m2) is the same (kind of).
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This is exactly what I saw comparing my new convoys to the Nemo.

I didn't see a significant difference. However this is probably good as, it might just be similar LED, just four of them to spread the beam out a bit.

So better than adding PTFE to expand the light circle of the convoy.

I still need to try the light painting mode (live composite mode) on my Olympus camera with these.

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Another factor is the battery's charge status and interna resistance.

As the Challenger, Nemo draws much more current than the Convoy all serial resistance in the circuit will be much more limiting to the output light.

The convoy is forgiving in a way the Challenger is not.

 

Unfortunately my Blak-Ray meter has died, so I could no repeat Steve's test.

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The Nemo center spot looks uneven to me, kind of mottled. This would not be a problem for light painting, but it might be for other applications that require even illumination or where repeatable illumination of a small spot is required.
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That is due to the lens on Nemos's LED with four chips.

If a small bright spot is needed the Nemo is not the one to use, but that often was a problem instead of a merit for the Convoy.

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It would be interesting to find the brand/model of the LED used in the Nemo, and maybe find more info on it.

 

Ulf, If you pull the sensor out toward the front (it plugs in with two contact prongs), then take the metal screen off it, you will see the size of the sensor filter. That is the maximum area the meter is seeing.

It i not square. Anyone who has one of those meters, it is interesting to take a look at the size.

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Unfortunately the meter is not responding at all.

I'll have to take it appart.

 

The metal screen was stored separately in the box, so I have seen the sensing area with the filter.

Anyway thank you for the tip.

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Convoy S2+ (with newer Nichia NCSU276C LED) and 'Nemo' mA tests, fresh batteries, using Fluke 83 multimeter.

Convoy = 1072 mA

'Nemo' = 1765 mA

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Convoy S2+ (with newer Nichia NCSU276C LED) and 'Nemo' mA tests, fresh batteries, using Fluke 83 multimeter.

Convoy = 1072 mA

'Nemo' = 1765 mA

 

That makes sense as the newer convoys have three 7135 chips (3x350mA=1050mA).

Whereas the Nemo, at least mine, has five (5x350mA=1750mA).

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Not sure if the battery itself makes a difference, given that I tried it earlier with a different battery, which was also fully charged, but it gave a lower reading, around 900 mA.

The battery used above was a more expensive battery, has built in protection, got it from the place John recommended, from this place:

https://liionwholesa...batteries/18650

As I remember the battery has a lower labeled mAh, but I never trust those ratings anyway, but the label on the battery is now completely worn off of all 4 I have of that type, so I don't really know more about it.

I don't know if the battery can be a mA factor other than the charge or not. Ulf would probably know.

 

Added:

I looked up the original battery order, 2017, the same model they have listed/shown now looks different, but same part number:

https://liionwholesa...ant=12534255236

The silver/gray label on mine has the writing completely worn off now.

These are the most expensive 18650 batteries I have ever purchased, most of mine are much cheaper,

they all seem to work fine, I have never compared them directly.

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The quality batteries you have are likely with a reasonably honest capacity label.

It is not easy to squeeze in more than 3500mAh in a 18650.

The rest have "marketing" labels.

For 26650 the real capacity limit is about doubled.

 

The key parameter for the Nemo is batteries with low internal resistance as their output voltage is kept more stable when loaded.

Cheap "9000mAh"- and similar- batteries with actual low capacity almost always have a high internal series resistance and when loaded the voltage drops much.

 

As 26650 batteries are bigger the physical shape makes it easier to get low internal resistance and even a bit cheaper types might deliver full UV-power directly when fully charged.

However the point when the light starts to decay is reached faster.

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I only have a selection of various quality 18650, so that is all I can compare.

The question would be, would a higher quality, or different 18650 batteries deliver different current, to the same device, even when they are all fully charged?

 

I only have one type of the 26650. But the question still pertains.

 

In other words, given better 'quality, or just 'different' batteries, would there be differences in the current output when fully charged.

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