is it just me - or where can I get a red emitter with lumen >150 ??

Hey all,

I'm looking for hours now ... maybe it's me but I wasn't able to fin any red emitter > 150 lumen available on the internet. The only one I found is a Seoul 3.5W Star LED (P4 Version) with 108 lumen at 800mA but it's too less for what I planed to use it for.

any sugestions :thinking:

Simon

Could you not use a more powerful white LED and a red filter?

You realize that the eye is less sensitive at red, and that 100 lumens of red light is a serious amount.

Using a red filter on a white led does not seem a good idea. You would need a p7 at least to reach the amount of that red light.

I'm moving this to the LED (emitters) section for you.

IMSabbel said:

You realize that the eye is less sensitive at red, and that 100 lumens of red light is a serious amount.

Using a red filter on a white led does not seem a good idea. You would need a p7 at least to reach the amount of that red light.

Click to expand...

... oh I didn't know that - really I can't imagine 108 lumens are "bright"

what I wanted to do is mounting my old huntlight (p60 host) onto my bike's seatpost and make a drop in out of some leftovers (cheap dx driver board with silly strobe modes) and a red emitter ... so that I can race through the nights with a real bright red strobe in the rear

so you mean the red Sould P4 is sufficient for what I want to do ?

Here you go:

http://www.luxeonstar.com/luxeon-iii-emitter-led-redorange-lambertian-190-lm-1400ma-p-73.php

Don't wait too long, though; they are slated to be discontinued...

It says it can take up to 1.4 amps...whether that is somewhere you want to go, and something you can provide adequate heatsinking for........

Enjoy!

LEDAdd1ct

A little while ago I build a light based on 5 Rebels - I had a few boards with different LED tints and, just for fun, I made a version with the deep reds.

I was going to use it as a rear tail light but it turned out to be too bright.

These LEDs were rated at 65lm at 700mA, so five of them should give ~325lm

Here is a picture to give you an idea of the output despite the rather measly lumen figures.

how about this one? 317lm :devil:

http://www.newark.com/ledengin/lz4-00r110/power-led/dp/16P3151

or this one, which is a little cheaper...

http://www.newark.com/optek/ov4zrrrr/led-lamp/dp/45P8002

I'm gonna go ahead and say this, even though you'll probably do it anyway. Putting a 100+ lumen red light on the back of your bike, particularly in a p60 module as you're intending is bad for two reasons.

The first is it's far too bright. I have two PB superflashes (conservative geusstimate, 15,maybe 20 lumens each, with wide lenses) and they're bright enough to painful to look at for any length of time, particularly when it's dark.

Second is that you will not find a reflector for a p60 host that gives you the right beam part for a rear light (where the priority is being seen from as wide an angle as possible).

All you're going to do is **** off people directly behind you (potentially endangering them, and yourself by blinding them with glare) whilst still being no better seen from the side (where the real danger is on a bike) because you've got the light stuffed down a 20degree reflector.

By all means go ahead and build your own, theres some great designs in the bike light section. but at least exercise a degree of common sense. You wouldn't use a 7/800 lumen off-road headlight in traffic would you?

red SST-90 from luminus devices...something like 600-800 lumens of red, nailbender should have some in P60 format that he will sell, check his sales thread

One aspect that might help is that most rear tail lights and stop lights are technically "red - orange" - nominal 615 - 625nm sort of range.

At that wavelength, it is quite easy to get what you are hoping for.

:twothumbs wow guys thanks for your helpful input. I really appreciated it - your advices are very helpful to me - lovecpf
I think I'll go for that red Luxeon III and of course I'll inform you how it turned out in the end. I hit on a few ideas these days

@ herulach: of course I have this in mind and it's nothing new to me after many years of racing through the city at night and lots of direct face-offs... and it's even illegal here to have a light brighter than 3W (and battery powered are illegal as well). But anyway ... I'd rather **** someone off knowing he recognizes me than observe the law and feel insecure ... but of course your are right. It's jut a personal matter of taste ...

Note you can get red dropins from either DX or Kai.

Regarding brightness... heres a 1W red cree next to a common blinkie (cateye LD1100). Beam is much bigger but not significantly brighter.

SST-90 Red:

http://www.luminus.com/stuff/conten...st_90_rgb_product_datasheet__illumination.pdf

Look at the Osram diamond dragon. You can find them in red or amber. The amber (625 nm) looks pretty close to the wavelength of luxeon III red (627). I suspect they look red. They should be a useful replacement for the discontinued luxeon IIIs, of course you'll need different optics.

The diamond dragon can be driven up to 2 amps and produce something like 234 lumens. 2 of those should be enough for any bike light :twothumbs

I know mouser and digikey carry the diamond dragons, but I think only mouser has the amber.

Mark

one thing i didnt see anyone cover is that lumens rating is based on beam angle and MCD of the led.
http://www.ohmslawcalculator.com/mcd_to_lumens.php
been using that converter to figure out some led lumens ratings. one led i have been messing with is stated to be 256k MCD with a 7k color temp with a 40 degree beam angle. the other is a 45k MCD, maybe 6-7k color temp, with a 120 degree beam angle. i have to say while the second one isnt as bright as the first. though i thought it was about just as bright since both were a blinding while about 6ft away and looking at them.

Evilsizer said:

one thing i didnt see anyone cover is that lumens rating is based on beam angle and MCD of the led.
http://www.ohmslawcalculator.com/mcd_to_lumens.php
been using that converter to figure out some led lumens ratings. one led i have been messing with is stated to be 256k MCD with a 7k color temp with a 40 degree beam angle. the other is a 45k MCD, maybe 6-7k color temp, with a 120 degree beam angle. i have to say while the second one isnt as bright as the first. though i thought it was about just as bright since both were a blinding while about 6ft away and looking at them.

Click to expand...

That calculator makes some assumptions that aren't neccessarily true.

Candela is a measure of intensity, while lumens is total light emitted. Its fairly unlikely that the peak intensity (which will be what's quoted) is maintained across the 'hot spot', with bare emitters thats certainly not the case.

The best way to subjectively test the relative brightness of the LEDs is with a ceiling bounce rather than looking directly at them, your eye can't deal with bright point light sources.

The Dane said:

SST-90 Red:

http://www.luminus.com/stuff/conten...st_90_rgb_product_datasheet__illumination.pdf

Click to expand...

Assuming you can actually afford them. AVNet sells them at $36.67/per-unit without shipping.

I still like the Luminous SST-90's in spite of their price. IIRC, driven at 10W a 4000K SST-90 will put out roughly 60W worth of light.