OT: flashlights again

Mar asked if I might enjoy Chinese tonight. That's femglish for "I don't feel like cooking". Roger that. We went to the pretty-good
Chinese place, ordered some takeout. While they were getting that ready we went down a few doors to bum around in the Goodwill. I spied a hishlight, ohmygosh. I almost resisted it, but Mar said I *must* buy that hishlight for $4.99. This is an instance of the orignal "hishlight" my Dad brought home from Camp Perry for me before he deployed to Guam in WWII. I was a very little boy, too little to say "flashlight" (hence the term hishlight) but apparently not too little to love it instantly and once clock a matron in the forehead with it who'd tried to relieve me of it as being too heavy for a tyke. MY hishlight -- bonk! I barely remember that event other than that I was being held aloft by someone else at the time , probably Ma. Ma laughed about that for the rest of her life whenever the subject of flashlights came up. It ain't a replica, it's the real thing: the L-shaped MX-991\U with O-ring seals. I'm quite sure it's not a Chinese knockoff because it says "made in USA" and the threads on it are inch (12 TPI) not metric. How could I not have a real "hishlight" at Donnie's house, 60+ years later? There is a threaded ring missing from the front. I can easly make a replacement, though it won't be olive-drab. There are some filters stored in the endcap: a faceted clear diffuser (flood), a white diffuser (tactical) and a bluish-purple filter (signalling?) The switch has a mid-position where a little adjacent pushbutton can be used for signalling in morse code. It works. There probably was also a red filter in there originally. The belt/webbing clip is not sprung and the metal slide-switch works fine. Both are brass, or maybe phos-bronze since they're springy. Some of the black is worn off of the metal. I don't think I'll try to restore that, just leave it as "experience". The rest of the light is in excellent condition. The reflector is metal. Other than Pelikan, what's the last flashlight you've seen with a metal (not metallized plastic) reflector? Maglite reflectors are metallized plastic. This flashlight model was in military use during WWII and 'Nam, presumably Korea as well. Don't know how long after that. It's probably not quite as robust as a Maglite, but it's not far behind it and it's a hell of a lot lighter in weight with batteries. It's flat base and L-shape enables it to stand on a flat surface and point at something you need to work on with both hands. There's a flip-out ring recessed in the base for hanging the light on a caribiner or whatever when the belt/webbing clip might not suffice.
Good functional design is almost timeless. A google search got zero hits for actual units or even knockoffs, but there are plenty of models and action figures that include a model MX-991\U as part of their kit. It is unremarkable as a source of illumination: it's a plain-vanilla 2D flashlight in that regard, not as bright as a Maglite 2D. As you might guess, I think I'd like to fix that.... I'd like to fit it with a Carley #1908 or #1937 deep paraboloid reflector and a 3-watt Luxeon. The reflector in it is in mint condition but a deeper short-focal-length paraboloid would work better with a Luxeon.
http://www.carleylamps.com/reflectors.htm
(I recently learned about Carley from a poster on RCM. Thanks!) I think there's ample room for drive elex in the head. A pair of D cells will run a 3-watt Luxeon for quite a while. I tried a 3-watt Lux tonight in a slightly smaller reflector I had at hand (from a Pelikan flashlight), compared spots on the wall side by side with this light with new batteries. Very similar spot size, HUGE difference in whiteness and brightness. The Luxeon-ized MX-991\U would put a 2D Maglite to shame and would meet or beat 3D Maglites with krypton bulbs -- with less than half the weight. The elex will also keep it running bright throughout battery life, quite unlike any incandescant flashlight including Maglites. And, like most Luxeon lights, the spot will be absolutely free of mottling and filament image artifacts. The more I think about this the more eager I get to do it. Given my "hishlight" history, I gotta do it. I can just imagine Olga (Ma) and Big Don chuckling. I'll be on the lookout at "old stuff" stores, in case I see an original threaded nose ring, but I'll make one of black delryn for the interim. I suppose I could also make it of aluminum and anodize it OD... Fun, huh?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 14 Oct 2005 02:02:55 -0500, Don Foreman

When you get it up and running, post the project please
Ive got about 4-6 L head military flashlights and converting a few to LEDs would be cool
Gunner
"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

OK. Don't hold yer breath, but I will get around to it sooner or later.
This conversion probably wouldn't be too pricey if several guys did it. The hooker with buying Luxeons, circuitboards and probably reflectors is minimum charges plus inflated shipping -- which can be minimized if spread around a little. Example: 3-watt Luxeons are $8.50 each. Elex parts would probably be $5 to $10. Circuit boards are about 60 cents per flashlight but there's about $50 of overhead per lot.
Barter works: for example, I might stuff a circuit board (surfacemount parts, need a microscope) in exchange for a genuine nose ring and red filter.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 14 Oct 2005 11:55:20 -0500, Don Foreman

You need GI parts? Let me check..hell I can probably send you an entire flashlight.
Gunner
"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Cool
Pending a look at how well the Carley reflector works, I'm moving toward a 1-watt Luxeon rather than a 3-watt for this light. 1-watt with a good reflector compares very favorably with a 2D Magite in brightness and is WAY brighter than the standard MX-991\U. It has more than half as much output as a 3-watt -- go figure, but that's what the specs say: 45 lumens vs 80 lumens. That's plenty of light, much better battery life (25-30 hours on 2 D cells at full brightness), no heatsinking problem, simpler elex.
Half output power produces considerably more than half perceptible brightness due to how our eyes work.
Most of the available 3-watt lights run on 6 volts -- typically two 123 lithium cells. I'm now seeing why: it has to do with the elex. They're good lights, but 123's are pricey and don't contain nearly as much energy as D cells.
The 3W would be a neat "showoff" light but the 1W is more practical.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
If I remember my physics. It requires ten times as much light to look twice as bright. Karl

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 16 Oct 2005 12:05:22 GMT, "Karl Vorwerk"

It's logarithmic, but I haven't found a reference that says what base log it might be or what multiplier factor would be "right". I wonder how one can say with any certainty when something is "twice as bright".
Bell (Alexander Graham) reckoned that sound must increase 10X in power to sound twice as loud, hence the Bel -- a ratio of base 10 logs and the more commonly-used deciBel which is 1/10 of a Bel.
I can attest that a 3-watt Luxeon looks "noticably brighter" than a 1-watt, but it isn't twice as bright. Reflector size and shape are much more important in realizing a "good" flashlight. That's one reason Maglight 2D's are "good"; they have a fairly large reflector that is quite deep with short focal length, so more of the light is collimated and less is spilled. A 1-watt Luxeon in a 2D Maglite reflector makes a damned good flashlight!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Inverse square law for light. Check out the hpyerphysics pages - E=I/r^2
Martin [ rusty in his Physics so I bought Hyperphysics web pages ] Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder
Don Foreman wrote:

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 16 Oct 2005 21:46:05 -0500, "Martin H. Eastburn"

That deals with distance, Martin. It has nothing to do with perceived brightness produced by two otherwise identical lights at same range but of different luminous output.
Measuring perception is "soft science". How can one know one light looks twice as bright as another rather than 1.8 times as bright? Maybe the human factors folks have devised a way to do that but I've not found it in the literature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Then use the oil spot test.
Power Per Unit Solid Angle
The power (flux) per unit solid angle (sometimes called pointance) is the nearest precise terminology to the common term intensity. It expresses the directionality of the radiated energy and is appropriate for the description of point sources. In the case of radiant power, it is expressed in watts per steradian. For visible light it is expressed in lumens per steradian = candela. Calculation to be added.
If the intensity ( I = dF/dw ) of a source is the same in all directions, the source is called isotropic. Otherwise, for a flat radiating surface, known as a lambertian, the intensity falls off as the cosine of the observation angle with respect to the surface normal.
Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder
Don Foreman wrote:

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 17 Oct 2005 21:06:35 -0500, "Martin H. Eastburn"
Say more about that please. Doesn't the oil spot test change the amount of radiant power observed?

All true, but the relevant measure of "brightness" for a flashlight would be light reflected from an illuminated target. Seems to me that measuring how perceived brightness increases with increasing power would best be done with the same reflector or collimator (hence same beam angle in steradians), same target and same target distance so the only variable is power.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
It has been (blush) 40 years since playing the game - in the lab...
Ok - on a card stock cut a nice hole. Across the hole put an oily tissue or such that is stretched tightly.
Now place the two lamps at the end of a 12" or 20" or some length. It needs not be perfect. The card is placed on a carrier that rides on the length of wood or meter stick..... Now in a dark room - look at the oil spot. Total blackness ! - Got You!
Have to light each lamp on the ends with precision voltages (same measured to reasonable accuracy). It can be a battery and a pot that provides a specific VI across and through the diode or lamp and make the other one the same.
Now if one has a 6v lamp and a 12 volt lamp - then make the lamps to their specs.
Once lit, the two lamps have a distance to shine towards each other. The oil spot between. Now with the lights out, look at the oil spot. Do you see the other lamp - through the oil ? move it away from it... until it just goes away. Measure the distance to the oil spot from each lamp.
...
The math is left to the student - but one can easily tell if one lamp is stronger than the other - as it drives further. Inverse square law is law here...
Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder
Don Foreman wrote:

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 17 Oct 2005 22:56:06 -0500, "Martin H. Eastburn"

Why not simply use an old photographers light meter? and measure them both, if one wants to be picky..I suppose you could use reflected on a grey card.
Gunner

"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

If it helps, each doubling of light energy equates to approximately equal steps of human perception. Photographically speaking, one f/stop corresponds to doubling/halving the exposure time or aperture area. So there it is: human perceptive response is exponential, roughly 2^^n.
Why "old"? They still innovate and make new meters that work on the same (old)principles. Maybe it seems novel now that some don't come with an attached camera. :)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 18 Oct 2005 09:28:18 GMT, "Mike Young"

"Old" in that few people today buy one, as they did in the "Old Days"
I have about 15 of them...from a very old #2 Wesson to several Sekonics. I use them whenever I drag out the TLRs or the 4x5s, which in the last few years, has been unfortunately rare.
None of the cameras came with metering...least of all the Linhoff.
The some of the Nkons have em..others dont. The S1 has an add on. The Canon A1s of course..shrug..do.
Which I suppose could be used to evaluate the light outputs, if one set a nominal ASA rating, a slow shutter speed, then viewed reflected on a all or grey card...and see what the f-stop differences were.
But a Sekonic might be a better thing..as it will give you candlepower if you so desire.
Hummmm then I suppose one could dig up ones old enlarging meter....
<G>
Gunner
"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I have a Toyo. From time to time, I think I'll reinvent the view camera; use the new smaller|lighter|much more expensive linear motion goodies of today, and get rid of the stiction and backlash in the movements.

A spotmeter will probably do a reasonable job with a point light source, although I'll happily send you the cheapie Ilford meter if it surfaces without much digging. It's still pretty new; I only turned it on long enough to plumb its depths and exclaim "What a piece of SH*T!"
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 18 Oct 2005 12:09:07 GMT, "Mike Young"

LOL...I think Ive got one too out in storage, along with the two Omega D2 enlargers..which Ive not used in at least 15 yrs. Someday Ill start up a dark room again. Least Ill think about it and drag my feet and the next of kin will have to deal with the stuff....
Gunner
"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Gunner - that is a D22 I bet. I have a 2 1/4 x 2 1/4 one upstairs now. Got it in 64 when living on island. Last time used it - when in Austin. Have to get it out and stock up on chemicals - those are getting rare.
Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder
Gunner Asch wrote:

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 18 Oct 2005 20:52:30 -0500, "Martin H. Eastburn"

They are whatever the 4x5 versions are. IRRC its the D2..but Im often wrong.
Gunner

"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
OH oh - I may have boo booed.
Maybe a 4x5 /2 is a D2/2 or simply D22.
Forgot you had a 4x5 - I once had a beautiful 11x17 battle field view camera. I could not lift the tripod. I think it was 25 feet tall when spread. Kept it in a Storehouse. Left it in the islands - once again attached to the News paper looking for another good home. Once was a U.S. Marine official camera that took the major pictures of Kwajalein Atoll. Most of my shots were with 4x5 and once 8x10. I didn't have developing trays for 11x17 - the film was 'easy' for me to get. Just a call.
Martin
Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder
Gunner wrote:

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.