LED 'Flow'

[Just Plain Jeff]

Mango shares with us the following (from some other, totally unrelated thread):

Now I'm the first guy to promote a full scale LED attack. However, at the risk of bringing down the ire of my peers, I have to comment on taillight LED's.

Unless your doing what Dale did on his bus (very nice job by the way - your wife must've done the work) by replacing the entire fixture I would not just subsititure LED bulbs for the existing bulbs in the same fixture. Reason being is the new LED bulbs do not provide an even "flow" across the lens fixture. It's more of a concentrated light bead in the center of the lens that from a couple of car lengths behind the coach just doesn't quite look right.

I'm in Jon's Dark Side camp on this one.

Mike

Let the flamin' begin.
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The purpose of this thread, and certainly it will stay on topic, is to better understand the term of 'flow.' Are we talking an aesthetic, thermodynamic or electronic flux capacitance issue here. Before someone launches a frontal attack, we need a better definition of terms here.

How the heck can a guy driving his bus know what it looks like a couple of car lengths behind? Perhaps, instead, this is a commentary on someone else's handy work?

Help me understand, this is all NEWBIE to us at this end.

Creepers, when we hit 40, we won't be able to keep pace with y'all.

[Jon Wehrenberg]

That is what you stand on.

[rmboies]

That is what you stand on.

bahahahaha, only in the south Jon:D Good one!

[dalej]

Jon, how do you stay sharp as a tac? You must have stuff up there we can only dream of. :)

[MangoMike]

Obviously we didn't invade some poor defenseless nuclear laden middle Eastern country today as it would explain why Jeff has had a bad day at work.

Let me explain:

First off my comments were not outside the Thread as it has to do with installing rear LED tail lights as done by Dale's wife.

Jon's description of FLOW non withstanding, has to do with the even spread of light across the colored lens. Garyde would equate it with a Spot Bulb vs a FLood Bulb. An LED in your existing tail light assembly will just spot the back the lens, whereas the current bulbs will FLOW with light.

Making absolutely no difference to the individual(s) driving the bus it does bug the anal light sensistive guy following.

mm

[rfoster]

Before Ledshttp://i52.photobucket.com/albums/g31/parkwayautoofbristol/CIMG0476.jpg

After LEDS:
http://i52.photobucket.com/albums/g31/parkwayautoofbristol/CIMG0477.jpg

[MangoMike]

Fast Roger,

As Delicious Debi would say - BAHAHAHAHA.. You make me laugh.

I know as soon as you read my post, you grabbed your digital and headed for the dungeon with Micki in tow to work the brakes. You have way too much free time.

mm

[rfoster]

Mango: Just imagine some of the scenes from the Old Frankenstein Movies, Down in the dungeon with the sparks a flying. I woke him up to get the photos. BTW A1 2Plane, my best friend, Leak Detector in Hand Jon is coming to the Dungeon in the am. Snow is expected, he may have to camp out/in. Full report tommorrow nite at 11
In other news - we have new nominees for the Anal Award.
.:cool:

[garyde]

In my world, we call that difussion of light reflectance or optical difussion. In laymen's: Beam spread or light reflectance. Now that we have that cleared up, we need to be more careful on what we post, I can just see Roger just waiting for the next Post, Camera , etc. ready.

[MangoMike]

Ok Gary, let's get you on the ledge.

Which provides better light reflectance in the Prevost tail light housing. A LED bulb or the traditional incadescent.

MM

[garyde]

Well, I could say its in the eye of the beholder. From a subjective point of view, the LED lights are crisp and sharp, but it seems you need more to fully illuminate a lens. The lumens of a Led lamp appears to be higher than a S lamp but the glow or spread is less. Hope that clears it up!

[win42]

We were sitting behind a small ford with it's LED brake lights on last night and I was getting flash burns through my 72 year old cataracs.
If you want to keep your existing tail light lenses, add red LED lights behind clear lenses. If someone comes up behind a SS bus and can't see it, they don't belong on the road. Now what other trivia can we waste our time on.
YEEEZ

[MangoMike]

Ok.

I never questioned the intensity of LED's. All I'm saying is that from an astectic reasons, incandescent bulbs give a better "FLOW" across the lens.
As opposed to beady eyed LED approach.

mm

[Jon Wehrenberg]

OK, if you guys want technical, sticking an LED bulb assembly in a light designed to use an incandescent bulb may have less than satisfying characteristics because the fresnel pattern may have been optimized for a filament bulb.

Gary can confirm this and also indicate I speak truth. I didn't make this one up.

[rmboies]

Fast Roger,

As Delicious Debi would say - BAHAHAHAHA.. You make me laugh.
I know as soon as you read my post, you grabbed your digital and headed for the dungeon with Micki in tow to work the brakes. You have way too much free time.
mm

Hmmmmm, DD, has a nice ring to it:D

[JIM CHALOUPKA]

Yes and no, The lense does come into play, but the shape of the reflector and the position of the lamp filament or the led light source in the reflector and how the light is focused onto the lens has an equally important role in the quality of light emitted from the fixture. ;) I have never heard of light characteristics described by "flow". :confused: Someone please en..light..en me. :D are we making up answers here?

[garyde]

Yea, John is correct. The incandescent lamp is designed to reflect light off the back of the lamp housing and to illuminate thru a lens which increases its light. The LED lamp is designed to stand alone as its own lamp and does not have reflectance. That is why you typically see more LEDs in a Lens. An example would be a typical Stop light. The red/yellow/green used to have a standard long life A base lamp bulb. Know each color has approx. 30 small LED lamps. The benefit is you don't have to replace the lamps every 3 months.

[jello_jeep]

Do you think an ellipsoidal reflector would be more efficient in this regard? :confused:
(sorry, couldn't help it)... :rolleyes:


OK, if you guys want technical, sticking an LED bulb assembly in a light designed to use an incandescent bulb may have less than satisfying characteristics because the fresnel pattern may have been optimized for a filament bulb.

Gary can confirm this and also indicate I speak truth. I didn't make this one up.

[Jon Wehrenberg]

The bulb replacement interval is always cited as a reason to switch to LEDs. In the 15 years we owned the first coach we never replaced a bulb in the side marker lights.

I replaced a lot of bulbs in the top front and rear clearance lights (the wedge type), but I can't recall doing that every year. It seemed like every couple of years one or two would need to be replaced.

I never had to change a turn signal bulb, but did have to change several parking light bulbs until Prevost changed them I think they went to a lower wattage and possibly from a 24V to a 28V.

I only replaced two stop light bulbs.

I would switch to LEDs if I could replace the entire stack in the rear with assemblies that were direct replacements and were designed as LEDs. I like the way the LED lights "snap" on, and their "in-your-face" intensity.

[MangoMike]

I would switch to LEDs if I could replace the entire stack in the rear with assemblies that were direct replacements and were designed as LEDs. I like the way the LED lights "snap" on, and their "in-your-face" intensity.

Ahhhh.... We're starting to have just a hint of movement from the Dark Side.

[rfoster]

Mango, Tom:

Do you see the effects of hanging around with me? Next thing you know he will be trading his low mile Mercedes for a BMW.

[Jon Wehrenberg]

Don't look for big things to happen quickly from the dark side. I am still not sure personal computers will catch on so I am going slow here too.

[truk4u]

Roger,

Now I'm worried, I thought he was the last hold out with me on the dark side, but now I wonder if his priorities are getting a little out of wack.:confused: I think the belt buckle put him over the edge!:D

[dalej]

Guys here is a little experiment that I did with 1157 bulbs. I hope this sheds some light on this subject.

Noted: I have seen LED 1157s that just have their LEDs facing out, so what Mike is saying is true. Superbrightleds.com sells these type and I have seen these in auto parts stores. They sell for around 30 percent less then the ones we sell for Trux.

Check it out at.... http://midwestleds.com/1157LEDtails

[Toy Box]

Jon.. check out the lights from Bus Parts in Orlando. I can show them to you next month at Liberty. They were a 10 minute bolt and plug.

[Jon Wehrenberg]

TB, I'll want to see them. I like what dale showed. Most of the LEDs I've seen haven't worked well with conventional lenses because the pattern was optimized for a filament and the reflector based on that filament position, whereas what Dale shows is much closer to the light distribution of a filament bulb, but with the crispness of an LED.

But what will I do with my supply of bulbs????????

[JIM CHALOUPKA]

Jon, Usem up wear em out makem do or do without.:D JIM

[JIM CHALOUPKA]

Just Plain Jeff;Mango shares with us the following (from some other, totally unrelated thread):

Now I'm the first guy to promote a full scale LED attack. However, at the risk of bringing down the ire of my peers, I have to comment on taillight LED's.

Unless your doing what Dale did on his bus (very nice job by the way - your wife must've done the work) by replacing the entire fixture I would not just subsititure LED bulbs for the existing bulbs in the same fixture. Reason being is the new LED bulbs do not provide an even "flow" across the lens fixture. It's more of a concentrated light bead in the center of the lens that from a couple of car lengths behind the coach just doesn't quite look right.

I'm in Jon's Dark Side camp on this one.

Mike

Let the flamin' begin.
-------------------------------------------------------------------

The purpose of this thread, and certainly it will stay on topic, is to better understand the term of 'flow.' Are we talking an aesthetic, thermodynamic or electronic flux capacitance issue here. Before someone launches a frontal attack, we need a better definition of terms here.

How the heck can a guy driving his bus know what it looks like a couple of car lengths behind? Perhaps, instead, this is a commentary on someone else's handy work?

Help me understand, this is all NEWBIE to us at this end.

Creepers, when we hit 40, we won't be able to keep pace with y'all.
.................................................. .............................................
Here is a site that will probably tell you more about LED,s than you want to know, but I am sure there are some that will enjoy some part. :eek: :rolleyes: JIM
http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/leds.html ("http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/leds.html")

[Jerry Winchester]

Did someone call in an airstrike? Radially mounted LEDs in the new bulbs provide lots of light for lens coverage and reflectivity.

http://www.superbrightleds.com/tail-brake-turn.html

Whack, he hits it waaay out of the park.

LEDs = 1
Dark Side=0

[truk4u]

Stay on the dark side boys, don't let these LED weenies get ya!:D