Which is brighter?

Showolf · Sep 29, 2010

Can someone please clarify for me.... Which is brighter? :thinking:

Cree Q5 or XPG R5

I just ordered an ULTRAFIRE C8 with the XPG R5 emitter that is claiming 350 lumens, and I am curious if it would be brighter than the Q5 version. Its beam looked damn impressive in a picture I viewed online!

P.S. I also own a KAIDOMAIN RAIDFIRE SPEAR CLONE with the Q5... Will it stomp that in throw?

John_Galt · Sep 29, 2010

The R5 XP-G is more efficient than the Q5 XR-E, so, yes, it should be brighter, if the drive levels are the same.

Brighter, as in "more output", yes. If using similar sized reflectors, especially smaller, shallower ones, the XR-E based light may appear "brighter," but that is not due to increased output, but a higher lux rating (lux is the concentration of light).

sol-leks · Sep 29, 2010

Short answer is that the XP-G is brighter. Of course circuitry and battery configuation is also very important, but the xp-g is newer and more efficient.

AnAppleSnail · Sep 29, 2010

Showolf said:
Can someone please clarify for me.... Which is brighter? :thinking:

Cree Q5 or XPG R5

I just ordered an ULTRAFIRE c8 with the XPG R5 emitter that is claiming 350 lumens, and I am curious if it would be brighter than the Q5 version. Its beam looked damn impressive in a picture I viewed online!

What you need to do is read about Lux and Lumens - and then Cree bin codes.

Cree LEDs, single-die.
XR-E: Old. Small die, throws better in a given reflector. Up to R2. Higher lux.
XP-E: Newer
XP-G: Newest. Large die, lots more output. Up to R5. More lumens.

Bin codes:
Q2-Q5
R2-R5

Each "+1" is 7% more lumens at 350 mA. So an R2 is 7% higher-output than Q5, and an R5 gives 35% more photons.

Brightness: Lux or lumens?

"Lumens" is total light output. "Lux" is concentration of light. Think of a searchlight - it sends a narrow beam of light great distances. That's a "Throwy" light with high lux. It's great for seeing things far away or through fog, but not-so-great for working up close. Lux = lumens per square meter.

"Lumens" is total light output. The human eye is very easily fooled into thinking high-lux sources are brighter than low-lux sources. One common way to compare lumens is a 'Ceiling bounce test,' where you point each light at the ceiling and switch them on and off to see how bright the room is.

So you'll get more lumens from the R5, but maybe not many more lux. You'll probably see about the same lux in a wider pattern than on the Q5.

Showolf · Sep 29, 2010

Thanks for the input... I appreciate it! :rock:

The C8 I ordered seems to be intended as a throw light from what I could tell , and its reflector appears deep like the spear. I will be happy if its beam has long legs like the spear , and can hit far away objects well. I guess I will have to wait and see!!!!

Does anyone here own one? If so could you share your opinions on it? :naughty:

sol-leks · Sep 29, 2010

that was a great little summary. I actually didn't know that about the bin codes, and I've been here forever.

Watts Up! · Sep 29, 2010

AnAppleSnail said:
What you need to do is read about Lux and Lumens - and then Cree bin codes.

Cree LEDs, single-die.
XR-E: Old. Small die, throws better in a given reflector. Up to R2. Higher lux.
XP-E: Newer
XP-G: Newest. Large die, lots more output. Up to R5. More lumens.

Bin codes:
Q2-Q5
R2-R5

Each "+1" is 7% more lumens at 350 mA. So an R2 is 7% higher-output than Q5, and an R5 gives 35% more photons.

Brightness: Lux or lumens?

"Lumens" is total light output. "Lux" is concentration of light. Think of a searchlight - it sends a narrow beam of light great distances. That's a "Throwy" light with high lux. It's great for seeing things far away or through fog, but not-so-great for working up close. Lux = lumens per square meter.

"Lumens" is total light output. The human eye is very easily fooled into thinking high-lux sources are brighter than low-lux sources. One common way to compare lumens is a 'Ceiling bounce test,' where you point each light at the ceiling and switch them on and off to see how bright the room is.

So you'll get more lumens from the R5, but maybe not many more lux. You'll probably see about the same lux in a wider pattern than on the Q5.

Yep great summary. This should be automatically e-mailed to each new person that joins the forum as sort of a quick intro.

Showolf · Sep 29, 2010

sol-leks said:
that was a great little summary. I actually didn't know that about the bin codes, and I've been here forever.

Yes! I learned a lot from the summary... Respect to the poster!

Which is brighter?

Showolf

Newly Enlightened

John_Galt

Flashlight Enthusiast

sol-leks

Flashlight Enthusiast

AnAppleSnail

Flashlight Enthusiast

Showolf

Newly Enlightened

sol-leks

Flashlight Enthusiast

Watts Up!

Newly Enlightened

Showolf

Newly Enlightened

Similar threads

Latest posts