Nichia GS vs. DS

Which is brighter when both driven at the same power level? Which is a better buy?

GS is brighter, duno which is better I only have DS.

GS is a little bit brighter but in the opinion of some has an uglier beam. "Better buy" makes no sense--if you're talking about bare leds they're both basically the same price. If you mean the Arc AAA DS vs GS versions, the GS costs a little more but preferences go both ways based mostly on the beam profile and color.

In my experience (only with Photon ML's) the DS has better efficiency, better beam, better tint, longer rated lifespan and is so close in output as to not matter. IMHO, stick with DS's

Just so you know, the L.R.I. Photon lights use GS l.e.d.s.

The GS is slightly brighter, the DS has a nicer beam.

Also, the GS has 1/10 of the rated lifespan, which is IIRC still several hundred hours. Whether this is a problem depends on how you want to use the light.

Fallingwater said:

Also, the GS has 1/10 of the rated lifespan,

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For real? I can't recall reading this before. It's hard to imagine Nichia or the various manufacturers taking, to me, such a step backwards for a negligible increase in brightness. Say it ain't so.

Geoff

It is shorter than DS but I recall it was a couple thousand hours, not hundreds. Still if you figure this into how much the light will be on, it doesn't really matter.

Hooked on Fenix said:

Just so you know, the L.R.I. Photon lights use GS l.e.d.s.

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Yup, they do now. They have, however, gone through the complete spectrum of Nichias from 50' beam angle to 5600mcd 20' beam to BS to CS to DS and now GS. It's also not too difficult to obtain a bare DS bulb and bend it to fit a Photon (although I'm keeping my "real" Photon DS as they gold plate the leads for corrosion resistance and good contact)

The DS is, far and away, my favorite Photon. Really useful output on 1-2032 battery (say 6-8 lumens?) with great batt. life and is silly bright on 2-2016's (I'm guessin' 25+ lumens, brighter than my Streamlight Microstream for sure)

Fallingwater said:

The GS is slightly brighter, the DS has a nicer beam.

Also, the GS has 1/10 of the rated lifespan, which is IIRC still several hundred hours. Whether this is a problem depends on how you want to use the light.

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The DS data sheet indicates 1000 hours of "steady state operating life".

The GS data sheet indicates 500 hours of "steady state operating life".

cyberspyder said:

Which is a better buy?

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I bought 10 DS and 10 GS in the recent group buy. I paid the same price for both types.

Found out all of the above traits too late...after I bought a couple DX keychains to tinker with for my X1...but the main point is that it's very bright, and that's what matters the most to me. I guess I can live with the crappy beam and the colour (it's not that bad)...but the lifespan might be a problem...anyone have the specs for the CS?

cyberspyder said:

anyone have the specs for the CS?

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Here's the link to the data sheets: http://www.nichia.com/product/led-lamp-phi5.html

The only CS they list is for red LEDs. 1000 hours of "steady state operating life".

Black Rose said:

Here's the link to the data sheets: http://www.nichia.com/product/led-lamp-phi5.html

The only CS they list is for red LEDs. 1000 hours of "steady state operating life".

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What does steady state operating life mean?

Ok, I know the DS has a longer life expectancy than the GS, but which one is actually more efficient? Not just "brighter", but brighter using the same amount of power?

The GS is somewhat more efficient in lumens/watt than the DS. There is a thread with some measurements of various 5mm leds in the flashlight electronics section.

Black Rose said:

The DS data sheet indicates 1000 hours of "steady state operating life".

The GS data sheet indicates 500 hours of "steady state operating life".

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If I'm reading the table correctly these are just test results with 30mA forward current. This is not expected lifetime of the LED (i can't find this value anywhere on nichia site :thinking. According to this post nichia GS LED "lasts only a few thousands hours". Which is still better than only 500 hours

Flying Turtle said:

For real? I can't recall reading this before. It's hard to imagine Nichia or the various manufacturers taking, to me, such a step backwards for a negligible increase in brightness. Say it ain't so.

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It is so, as far as I know. It's unlikely to be a problem for many, though, since most people don't keep their lights on long enough for the emitters to die.

Black Rose said:

The DS data sheet indicates 1000 hours of "steady state operating life".
The GS data sheet indicates 500 hours of "steady state operating life".

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I think it was SilverFox who said that he'd had an email exchange with Nichia and they themselves told him about the one-tenth lifespan.