Lumens VS. Candlepower....and Surefire VS. Stinger

[**DONOTDELETE**]

Here's the situation....

I'm a cop in a Canadian City, and have a 9P SureFire which uses (3) lithium batteries. As most of you would realize, I prefer using the SureFire versus the department issue (2) D cell MagLight, as the difference between the 2 flashlights is: during a building search lighting up the whole room with the SureFire, or just putting a spot on the wall with the MagLight.

The problem is the lithium batteries is putting me in the poor house. I contacted a few businesses as well as SureFire and they said there is no conversion kit available to convert the lithium batteries to a rechargable system.

Therefore, I've been looking on the net at flashlights, and must admit my favorite thus far is the Streamlight Stinger XT HP, with 40,000 candlepower.

QUESTIONS:

-what is everyones experience with this Stinger XT HP?
-my old SureFire is 110 lumens (I Believe)...the stinger is 40,000 candlepower...which is brighter?....how do you convert lumens/candlepower?
-where is the best deal on the Stinger?

...etc...etc...etc ANYTHING YOU COULD ADD WOULD BE EXTREMELY APPRECIATED !!!

Thanks !

 

[Nerd]

QUESTIONS:

-what is everyones experience with this Stinger XT HP?
-my old SureFire is 110 lumens (I Believe)...the stinger is 40,000 candlepower...which is brighter?....how do you convert lumens/candlepower?
-where is the best deal on the Stinger?

From carley lamps's site : "Lumens = CP x 4 pi 1 CP=12.57 Lumens"

Doesn't that mean the US qualifies for 502800 lumens? Something is very wrong here.......

 

[MarcV]

I've got an 8NX that I'd be willing to swap for your 9P and some spare change (or other consideration).

I assume the light output would be equivalent, but the 8NX has a spare battery and charger, the very thing I'd demand. In my day (1970s) we loaded our KelLites with high amperage rechargeable D cells. These days you have gyms to go to for exercise so you would probably be much happier with the 8NX.

 

[sunspot]

Hello and welcome. You will get alot of opinions here. Here is mine. If you like the Surefire you hae, go to ebay and find the seller named carguy21. Find an auction for 223 batteries. Buy six for about $6+ USD. Split them open to get the 123's. Now you have twelve 123's for about $0.50 each.
Opinion #2. Buy the Ultrastinger. About the same length as a Mag 3D but thinner. 70,000 CP. A better beam than the SF 8 AND 9'S and the Mag-charger. Almost like the SF M3T.
Good luck to you.

 

[lightlover]

NakedDog,
if you buy an A20 body extender from SF, that will make the 9P into a 6-Volt rechargeable. (You'll have to add the B65 battery and charger cradle and transformer, etc.)
The B65 will power the 65 Lumen P60 for around 45? minutes, and the 120 Lumen P61 for about 12-15 minutes.

OK, that doesn't seem to be the answer to your situation, but it is an option. Any of our LEO members will tell you that you need a back-up light, maybe that would do ?

The general opinion is that Lithium powered SF's are whiter than the rechargeables, but that's a purist view - in action, it doesn't seem to make a big difference.

Jahn

Whoa sunspot - you think that 12 123's is enough !!

 

[rlhess]

Originally posted by Nerd:
QUESTIONS:

From carley lamps's site : "Lumens = CP x 4 pi 1 CP=12.57 Lumens"

Doesn't that mean the US qualifies for 502800 lumens? Something is very wrong here.......

<font size="2" face="Verdana, Arial">No...it's confusing. One candela (cp) is equal to one lumen per steradian. The 4pi conversion assumes an isotropic source (omnidirectional) like an A-lamp (standard Edison base lamp).

So, if your light evenly covers one steradian of angle, then cd = lm.

Most flashlights (UltraStingers on tight focus in particular as I understand it) cover less than one steradian, so the cd measurement will be higher than the lm measurement.

For example. My Surefire E2e is rated at 60 lm but produces a center hotspot of 1200 cd.

That means that the light is spread out (if it were even) over 1/20 of a steradian.

Now, some of you might be asking, "What is a steradian?"

It is defined as a section of a sphere whose area is equal to the square of the radius. There are 4pi of these in a total sphere.

So, if you have a 3 foot radius sphere, then one steradian will encompass 9 square feet of surface and the entire sphere's surface area would be 12.57 (4pi) * 9 or 113 square feet. Compare that to the bounding box of a 6 foot cube or 36 x 6 square feet (216 square feet) of surface area and it seems reasonable.

I hope this helps.

Should I change my screen name to nerd2 after this one?

Cheers,

Richard

 

[sunspot]

Originally posted by lightlover:the general opinion is that Lithium powered SF's are whiter than the rechargeables, but that's a purist view - in action, it doesn't seem to make a big difference.

<font size="2" face="Verdana, Arial">Have you seen the US beam? It's very white.

Whoa sunspot - you think that 12 123's is enough !!

<font size="2" face="Verdana, Arial">Good point Jahn.

 

[jtivat]

Trade your P9 for a P6 and get the rechargable kit for it. Also get a spare battery and the P61 lamp. You will have a light that is about the same size and brightness as your P9 and about 40 min. of run time.

 

[Big Tex]

I've got a XTHP and a UltraStinger. If the additonal size is not a problem, you'll like the US better. It blows away the XT but it doesn't have the rear switch which you probably want.

 

[poalcat]

rlhess -

Huh? Your post reminded me of why I dislike math and physics so much. You might as well be talking Martian .

Ever think of working for NASA?

Best regards.

 

[rlhess]

Poalcat,

EEEEEKKKKK...work for the government? no thanks.

It's actually taken me several months to become comfortable with these light measurements. CPF inspired me to really understand it. I think I do, now.

It really does make sense. Here is cutting to the chase.

Lumens measure total light output. Candlepower (candela) measure the illumination in one direction. They are NOT easy to relate, because the optics will modify the total light output by directing it.

You will have more lumens than candela in a very wide beam. You will have more candela than lumens in a very narrow beam. My post above attempted to explain where that crossover point occurred.

Yes, it's math and physics...sorry.

I actually don't enjoy learning the stuff...but I enjoy coming to an understanding of how it all works and why it works the way it does.

You should see the research all the "dirty bomb" and "flying into the nuclear generating plant" news scenarios have had me doing. Bottom line on that one, I'm less worried after the research than before.

Cheers,

Richard

 

[lightlover]

jtivat,
what I was saying is that a 9P with an A20 body extender will house a B65 - you don't need to trade in the 9P for a 6P or 6R.
Also, if you have a 9P, you can make it a 6-volt by substituting a Z20, "blank 123", and using 2 123s only.

If you're using a 9P + A20, there is a Z29 - a "blank battery" the same size as ~1.3 123s, so in that configuration, it will (again) take 2 cells.

The standard 9P with a P90 LA will give 105 Lumens for an hour, or with a P91 LA, 200 Lumens for 20 minutes.
The 9P + A20 and the B65 powering a P61 will give out 120 Lumens for 12-15 minutes, or with a P60, 65 Lumens for ~45 minutes.

Baffling - but Versatile ......

Jahn

 

[sunspot]

lightlover, this looks like a math test.

(a)120 lum (b)65 lum (c)10 min (d)none of the above

 

[**DONOTDELETE**]

1)WOW!...seems I opened up quite a 'can-of-worms' with the whole "lumens VS candlepower" debate. ...as most of you can tell, I'm quite the "flashlight/ battery virgin"!!! Thanks y'all for the input, however I'm still quite embarrassed to admit I still don't understand. Simply put; I know what I have (SureFire 9p with 105 lumens), and want to be able to compare that light power to something I don't have (i.e: other flashlight with a power noted in candlepower), as I obviously don't want to decrease my light intensity.

2)I went to a few of the web sites some of you supplied...thanks. However as most of you correctly assumed, a rechargable 123 battery is complete crap. For example, 1 of the sites has 2 rechargable 123 batteries & charger for over $100, and the resulting power only last 3 MINUTES !!! What the hell is the good of that? I can't even believe a company would market that!

** 3)**The most plausible option seems to be just hide my tears and buy the batteries. A good option supplied was to buy the bigger pack and break it apart, for the cheapest solution. Or another solution, just get rid of the flashlight all together. However as some of you will know, converting U.S.$ to Canadian$$, including the customs fees and shipping, most of the flashlight on the net work out to costing over DOUBLE the advertised price.

***** So who wanted to trade their rechargable flashlight with me?....and why?....sounds like a good trade for me !!!

 

[sunspot]

NakedDog. You did not open a can o' worms. This is a normal dialogue between different opinions because that is what it all boils down to. Opinions or what one likes. Candle power or Lumens are just a guide.
As a direct answer to your first question on your 9P, my Ultrastinger can beat your SF by a good bit. You can compare a US to a SF M3T.
As far as the batteries costing so much to ship to Canada (GST, et al., contact that ebay guy and ask him. It may not be so bad.

 

[**DONOTDELETE**]

Thanks Sunspot...I have a bid on EBay right now !

 

[sunspot]

Your quite welcome. I remember something about the UltraS. The switch is a bit difficult with winter gloves. Good luck on your bid. You should get it with the minimum. He has them all the time.

 

[jtivat]

Lightlover, I didn't realize what you where saying. You are right, your option would be easier and accomplish the same thing.

 

[rlhess]

The only way to really compare is to hold several of the flashlights in your hands at the same time and evaluate them under simulated use conditions. I know that is as hard as figuring out the math!

The bottom line is the numbers are not comparable in any accurate way IF the numbers could be trusted! Beam shots are good, and I think there are a few beam shots on the Web, but I don't have the links handy. Try searching on other Ultra Stinger (or US) threads.

I have two "1,000,000" candlepower rechargeable spotlights. I don't know how they come up with these numbers. I measured 100,000 and 65,000 for them.

Good luck!

Richard