Hi I am New. could you fill me in on terms

f22warzone

Newly Enlightened
Joined
Nov 21, 2006
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Ok i am not very big on flashlights i just wanted an upgrade from my 4cell mag and i was wondering if this was a good perchas now i dont kno much about lights and i have read a lil bit on the form and i got to admit its more complicated than laser talk. : )

Ok i recently bough a WF-800 3W Cree Q2 LED Flashlight (2x18650 4xCR123A 7.4V~17V) from DX sku 6965
with
Ultrafire 3.7V 2400mAh LC 18650 Protected Battery 2-Pack
DX sku 3287
and a charger for them now i was wondering is this a good set up? the only light i have ever ownd would be a 1AAA minimag and a 4D maglight. will this be brighter than them? also what is the diffrence between lums and lux? and p4 and q2? also about how many lums would a 4d maglight be?

Any help at would would be apreacicated

Thank you,
michael


 
Hi, f22! I'm not familiar with the set-up that you bought from DX, but knowing what the output of a Cree Q2 when pushed at the specs of that light, it should be EASILY brighter than your 4D Mag.

As far as lux and lumens is concerned: Lux is a light source measured at one certain point from a certain distance (i.e. it's a light intensity measurement that's synonomous with candlepower). Lumens is a measurement of OVERALL output (i.e. how much total light is being emitted). Lux is relatively easy to measure using a common lux meter. Lumens on the other hand needs to be measured using a device called an integrating sphere...not all that common and quite expensive. Some CPFers have devised "light boxes" that have proven to be pretty accurate in determining lumen output.

Your 4D Mag may have a higher Lux measurement than the set-up you ordered from DX (due to the Mag's larger reflector), but I can guarantee that the DX light you ordered will be putting out MUCH more overall light.

Hope that helped...

PJD
 
F-22 welcome to the forum. You really need to just take your time and slowly learn. It's like anything...it just takes a little time and you'll be fine. The light you ordered will be very powerful...You can't buy a light just on advertised lux or lumens or throw ect..Often you can find a review of a light you want...just enjoy your new light while you think what you want next!
 
man you guies are great and quick to. but you didnt answer the one question what is the diffrence between a p4 and a q2 light bulb? and yes i do want to learn about them lol i didnt think lights were that complicated i though it was just based on volts not the sutff it was made of. crazy i tell ya. anways thank you.
 
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man you guies are great and quick to. but you didnt answer the one question what is the diffrence between a p4 and a q2 light bulb? and yes i do want to learn about them lol i didnt think lights were that complicated i though it was just based on volts not the sutff it was made of. crazy i tell ya. anways thank you.

That designation is a rating system for the quality of a particular LED. It's difficult to manufacture them identical and consistent, so each individual one needs to be rated after production. I'll respond with a quote from another thread which answers your question perfectly:

Cree is an LED manufacturer, Their XR-E LEDs have many different bins. P3, P4, Q2, Q3, Q4, Q5, in order of efficiency and brightness. The cheaper lights might use the lower Bins and the more expensive ones might use higher bins.
 
Q2 is much more efficient. at 350ma input current you will have a lot more Lumens output than with a P4. I forget exactly but probably around 85 versus 120 Lumens.
 
cree makes the q2 and the q5.
seoul makes the p4

different throw, spill, lumens per watt characteristics.
q5 is the most efficent led bar none right now.
i heard even over the new rebel 100.
 
cree makes the q2 and the q5.
seoul makes the p4

different throw, spill, lumens per watt characteristics.
q5 is the most efficent led bar none right now.
i heard even over the new rebel 100.
Just to clarify that for the benefit of new people:
Seoul make a product called the P4, available in various brightnesses ('T-bin', 'U-bin', etc)
Cree make a product called the XR-E, available in various brightnesses (P4,Q2,Q5, etc, as in the chart above)

A term like 'P4 LED' can be ambiguous unless it's otherwise obvious what it's referring to.
 
I got my flash light to day and man is it great. its so much bright then my mag light even better than my 2 4D put together. now the next question i have is. will the Q5 fit in just like the Q2 or does it need modification. and also will it be any brighter. i rember reading some whare that the Q2 is brigther only becaus a Q2 flashlight dosent put out the necessary ma to power the Q5 to full brightness. now i was wondering is this true for the flashlight i have?
 
The essential difference between the Q2 and Q5 is that the Q5 is more efficient - at the same electrical power input, it puts out ~25% more light.

The Q5 Cree XR-E is the same physical size as the Q2 XR-E, though it's possible to buy XR-Es either 'bare' or pre-mounted on various shapes and sizes of circuit board.
At the simplest level, replacing one Cree LED with another can vary in difficulty depending how easy the existing one is to get to, how it is fastened down, and how electrical connections are made to it. Potentially it could be a pain, and there's always the possibility of breaking something.

In practical terms, a 25% difference may well not look like 25% to the human eye, and may not even be easy to notice. If you had two identical lights, one with a Q2 and one with a Q5, and someone else kept pointed them alternately at a target, but you closed you eyes for a few seconds each time while they were changing from one to another, it might not be obvious which was which. Even side-by side shining at a wall, the difference might not look great.

If I were you, I'd be tempted to save what I might spend on a Q5 Cree to upgrade your flashlight, and maybe put it towards picking up a 1x18650 light for times you want something a little smaller.
 
F22,
Since you have started with 18650s, I suggest you stick to them to avoid having to buy many different chargers. I also agree with uk_caver that you should get a 1x18650 set up. It is much safer than putting 2x18650s together in series.
 
Keep your new light stock! It's a great light, and there is a good chance that a Q5 might only be a small bit brighter. Unless you are experienced, I would take my time and learn more before changing Led's yet. Consider getting an inexpensive 3 Watt Luxeon lll light that uses a full size star. Then, you can try changing it with a Cree P4 star ( about $5-$6) for the practice. You'll have a light that is noticably brighter, and you won't take a chance of messing up a really good $40 light.
 
Since you already have a Q2 in the light, I'd wait till the R4s come out next year before upgrading.

Have you seen this thread? It might help with some therms.

The WF-800 is a great place to start with high power LEDs. Good throw and good runtime.
 
r4's? Ok so you really cant tell the diffrences that sounds good i will just keep it stock then. and i dont think i will buy a new light becaus this one is like just the right size it fits in most of my pocets and i really didnt buy the light for size was acutly expecting somting biggger orjust as big as my 4d mag but was very suprised when i saw this small thing and that it put out a ton more light : ). thanks for all your help on this and i will take your advise and just keep it stock.

thank you
michael
 
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