ZebraLight H502 XM-L

[peterharvey73]

So good so far, except for this:

"and all three with a frosted lens".

The 502 is a mule. It doesn't use a frosted lens.

Oh, I'll edit that.
I don't have a 502, but on photo, it did look not quite frosted as usual - it was more transparent - say semi-frosted?

[moozooh]

It's not frosted at all; look again, it's absolutely clear. The reason for exceptional beam width without hotspot is the lack of reflector.

[peterharvey73]

It's not frosted at all; look again, it's absolutely clear. The reason for exceptional beam width without hotspot is the lack of reflector.

Ah, it actually uses a GITD Glow in the Dark reflector...

[Brasso]

No. It doesn't use a reflector of any kind. The GITD is just there where a reflector would normally be, but it doesn't serve as a reflector. The 502 is like a mule. It's basically a bare emitter with a dome. The lens is just there to protect the led. No frosting.

[lampeDépêche]

The 502 is like a mule.

Just as a student of the English language, I am curious: where did this sense of "mule" come from?

I have to assume that it did not originate in flashlight terminology, but in some older usage.

Is there some origin in car mechanics, or military jargon?

Those who understand it right away--what images does it call to mind, or what comparisons?

[bbb74]

Seriously?

WTF - obviously I meant using the same emitter behind both optics.

Why don't u think before u post?

Your post appeared to be either stating the obvious and repeating what YoSeKi had already just said in the previous post, or disagreeing with his post. Given it started with a "Umm-" and had a somewhat patronising tone it appeared you were disagreeing with him, and given that you said that 80 degrees would always outthrow 120 degrees - with no further qualifications - it appeared you were wrong.

Keep in mind YoSeKi had already pointed out the large increase in power required to make a 120 degree beam throw as well as an 80 degree beam. He also discussed different die sizes playing a part. When I read your post it appeared you were saying that was all irrelevant and 80 degree would *always* outthrow 120 degrees.

As you have now clarified, that is not what you meant, so ok. It just read that way to me.

[Bolster]

Just as a student of the English language, I am curious: where did this sense of "mule" come from?

I'm also confused about the usage of "mule" in this context, explain please?

[psychbeat]

Your post appeared to be either stating the obvious and repeating what YoSeKi had already just said in the previous post, or disagreeing with his post. Given it started with a "Umm-" and had a somewhat patronising tone it appeared you were disagreeing with him, and given that you said that 80 degrees would always outthrow 120 degrees - with no further qualifications - it appeared you were wrong.

Keep in mind YoSeKi had already pointed out the large increase in power required to make a 120 degree beam throw as well as an 80 degree beam. He also discussed different die sizes playing a part. When I read your post it appeared you were saying that was all irrelevant and 80 degree would *always* outthrow 120 degrees.

As you have now clarified, that is not what you meant, so ok. It just read that way to me.

In most cases given the SAME emitter a narrower optic will have higher lux than a wider one.

Therefore, IF the H502 had an 80degree optic it would most likely have more lux than it does now with the 120.

As was said earlier- some of us feel this would be more desirable than the 120.
For others it would not as they like the extra coverage.

YoSeki has proposed that maybe more lux is not what those of us in the former group really want/need..


CPF is all about nit picking and sometimes armchair engineering sometimes real innovation.


there's already another thread about it anyways and theres nothing to argue about really as a well designed 80degree would
out throw the 120degree optic period - I should have said "tedious" rather than boring earlier.
blah blah blah

is there even an optic under the glass- and is the glass-or optic causing the green edge?
seems like it is as I have a number of XML lights and none have a green spill + it seems people with
the Rebel models are seeing it too...

[psychbeat]

oh yeah and I too wonder where the "mule" term came from?

is it from the McGizmo light?
Id bet those dont have a green edge

[peterharvey73]

No. It doesn't use a reflector of any kind. The GITD is just there where a reflector would normally be, but it doesn't serve as a reflector. The 502 is like a mule. It's basically a bare emitter with a dome. The lens is just there to protect the led. No frosting.

I see - the Zebralight website calls it a GITD "reflector" in single inverted comas.
Sneaky. We have to really read the fine print.
With essentially no reflector, it's a pure flooder...

[Esko]

No. It doesn't use a reflector of any kind. The GITD is just there where a reflector would normally be, but it doesn't serve as a reflector. The 502 is like a mule. It's basically a bare emitter with a dome.

No. It DOES work as a reflector. A non-directional one. Otherwise the lumens from 120 to 180 degrees would be either lost or reflected uncontrollably (~30% of the total output of the led, provided that the calculations presented a few days ago are correct).

It is very easy to verify. Turn the light on high and put your finger on the bezel so that it covers the led but leaves part of the reflector visible. You can see that the GITD reflector is shining bright whitish light. Those are the lumens emitted from the led in 120 to 180 degree angles, and reflected from the surface and (since it is transparent) the inner material of the GITD reflector and the surfaces below it. A white one would have been more efficient and wouldn't have any effect on the beam color, but this is what Zebralight decided to use (GITD green).

I wish that the discussion about the properties of 120 degree vs. 80 degree beam could be continued in the dedicated thread, too. Everything has been said in this thread already and many things have been said multiple times, but it has either been buried under other things, people have forgotten it or they haven't understood it. And with other people continuing to misunderstand others (not saying that it is intentional), same claims, explanations and misunderstandings seem to pop up again and again.

[peterharvey73]

To be technically correct, I guess it is a reflector, but a "diffuse" reflector - one which diffuses the light beam to produce incoherence.
Conventional reflectors have a mirror surface, to produce a more coherent light beam...

[lampeDépêche]

I'm also confused about the usage of "mule" in this context, explain please?

Thanks, Bolster--I should have checked Wikipedia myself.

But even faced with that array of possible disambiguations, there is still a little bit of work to do (i.e. it is not obvious that any one of them solves our mystery).

Our mystery is: what is the source of the use of "mule" to refer to a flashlight without any optics?

Surveying the choices on the Wiki page, I don't think it comes from the sense of "a type of shoe or slipper without a back". At any rate, the backs of my shoes and slippers are not that reflective (though they do have complex quasi-parabolic curves).

I don't think it comes from "a person who carries contraband", or "a person who transfers stolen money or ships stolen goods across country lines". LEDs are very precious to us, but not to most people. And you wouldn't really fool customs agents by hiding an LED on the top of a flashlight. ("They'll never think to look there!")

So my best guess is that it is related to a "development mule",
http://en.wikipedia.org/wiki/Development_mule

"A development mule or a test mule in the automotive industry is a vehicle equipped with experimental or prototype components for testing."

If you are testing (e.g.) new fuel-injection systems, then you might assemble a very simple chassis without anything fancy on it--no passenger seats, no upholstery, etc.. You would build just enough of the car to allow you to test the parts that you want to test. Keeping it simple might also make it easier to switch between the different versions of the component you were focusing on (omitting the hood makes it easier to work on the engine).

So too, if you want to test a number of emitters, you might build a "stripped down" flashlight body without optics. You don't really care about developing the reflector and lens and so on right now, you want to build just enough of the light in order to test the emitter. And doing it this way may also make it easier to exchange a number of emitters.

So right now, this is my best hypothesis: the use of "mule" in flashoholic jargon comes from the world of auto development. And the sense is: a simplified platform that allows you to test one component, while not developing the others beyond the stage needed to make the target component work.

Perhaps this word is also used in the broader world of electronic hobbyists? I could imagine that having been the path of diffusion (cars > electronics > flashlights) if people employed, e.g. a simplified amplifier "mule" in order to test different tubes.

Can any readers who are more proficient in English tell me whether my guess is on the right track?

[pjandyho]

Just as a student of the English language, I am curious: where did this sense of "mule" come from?

I have to assume that it did not originate in flashlight terminology, but in some older usage.

Is there some origin in car mechanics, or military jargon?

Those who understand it right away--what images does it call to mind, or what comparisons?

McGizmo came up with a reflectorless flashlight and call it the Mule. It became the norm in CPF whenever we talk about flashlight using only bare LED with neither optic nor reflector.

[thaugen]

We just had a new baby so my wife has been getting up every two hours to feed the little lady. My H502d has been left on L1 (2 lumens) for the past four nights in a row with an eneloop battery. This morning I checked the battery level and got 4 flashes! Way to go Zebralight!

[moozooh]

H502d. The Ultimate Babycare Flashlight.™ :D

[Bolster]

No. It DOES work as a reflector. A non-directional one. Otherwise the lumens from 120 to 180 degrees would be either lost or reflected uncontrollably (~30% of the total output of the led, provided that the calculations presented a few days ago are correct).

So what does this say about Spark's SD series, which uses a dark-anodized "reflector" on its light with 120-degree beam? Just wasting light.

[Brasso]

It may be reflecting some light, but that's not it's purpose.

[Cataract]

SCREW YOU GUYS! This thread cost me 70$ this very minute and now I have to wait for the mailman with my H502d. It better get here on time for my vacation or I'll hold you all responsible.

[Diablo_331]

SCREW YOU GUYS! This thread cost me 70$ this very minute and now I have to wait for the mailman with my H502d. It better get here on time for my vacation or I'll hold you all responsible.

I feel your pain! I have too many Zebralights because of all of you!

[Diablo_331]

It seems my last post was lost so here it goes again.
I received my 502c a few days ago. There is an obvious green hue around the outer edge but I can't really see it in real use so it doesn't bother me. I can also see some light leaking through around the switch boot so I guess this means that I got one of the less than water resistant duds. It's going back and I just may wait a few more months for a revision to be released. This is my first true flood light and I'm so excited that I'm not ready to give up on the 502c just yet..

Just a quick update from ZL customer service. They replied that the silcone boot is transparent with some black die. Part of the switch is thin to allow for flexibility and that some light will get through but it still should be water resistant. I guess the best way to find out is to dunk it in some water and see what happens. I'll report back after I do this.

I gave it the 'ol dunk test in my sink and moved it rapidly back and forth while under water. The light was on high during the little test. I was pretty nervous and really hoping that ZL customer service was right.

The verdict... It turns out that they were! It still works! So I guess there is no need to be worried if you can see light coming through the edges of the switch boot. I'm just curious to see if anyone can't see any light around the boot on their H502? I wonder if their is any variation in thickness? Is it like this on all of them?

[Bolster]

Light seen thru switch boot on mine, and it survived a 15 minute dunk.

[Ezeriel]

mine leaks.. it's not the button that you need to worry about. Take the battery out and place your mouth over the led lens portion and blow, air easily passes through mine.

I ended up putting wax around the lens, and then superglue around the lens, and then sucking slightly on the battery tube. I then scraped off the excess wax and glue, and now it's waterproof, but I'm not happy about it.

mine also has metal shavings on the inside of the lens.. and I'm not happy about it

the button cover is thin.. very thin on the edges.. so I dripped superglue in the gap there as well...

and this is a freakin $70 light!!

All the 80 degree vs 120 degree arguments seemed silly to me, but I can see where the 80 degree folks are coming from.
For walking around there are much better options out there, but for doing up-close work, it's a very good light.

...and it makes a great camping lantern.


..but it should have never made it out of quality control.

..just horrible.

...$70

...meh!

[nakahoshi]

I have 2 H502's and they both are perfect. I feel much better knowing why light was leaking through near the button. The run time has been very nice (as advertised) and I really love the 4 click battery gauge feature. No gimmicky external screen or led, just a hidden simple interface.

-Bobby

[Bolster]

mine leaks.. it's not the button that you need to worry about. Take the battery out and place your mouth over the led lens portion and blow, air easily passes through mine.

Very disturbing to hear of sealment issues with the new ZL. ZL has had reputation-bruising problems in this area before, and should have learned a thing or two about waterproofing!!! I had high hopes they'd learned a lesson from the early H501 moisture ingress failures.

My SOP with any ZL is to give it a dunk as soon as it arrives. Haven't had a leaker yet but I'd return it immediately if I did. No way would I try to fix it myself with wax and glue.

[Bolster]

I really love the 4 click battery gauge feature.

Anyone notice the flash gauge drops quickly? One night I tested at 4 flashes and a very short time later it was 1 flash. I wonder if it drops to a single flash very rapidly at the end of cell life, rather than being a gauge of quarters, as I thought it might be.

[RedForest UK]

It's probably a voltage based readout and so with Ni-mh is likely to remain high before a sudden drop near the end of usable capacity.

[nakahoshi]

Anyone notice the flash gauge drops quickly? One night I tested at 4 flashes and a very short time later it was 1 flash. I wonder if it drops to a single flash very rapidly at the end of cell life, rather than being a gauge of quarters, as I thought it might be.

Mine has been pretty accurate using Enloops

-Bobby

[Bolster]

It's probably a voltage based readout and so with Ni-mh is likely to remain high before a sudden drop near the end of usable capacity.

OK that makes sense. Yes I was using Eneloops.

[Ezeriel]

No way would I try to fix it myself with wax and glue.

nothing ventured nothing gained