Need Illumination on Spotlight Issue

Might anyone know if there is an H3
LED equivalent for a 100 Watt H3 Halogen spotlight bulb that will fit properly and focus to the same small round spotlight pattern the halogen bulb does? I have this spotlight on my boat, the same one that is commonly used for off road automotive uses. I would like to convert to LED to get a bright tight spot beam with much less wattage than the 100 W or even 55 W halogen bulbs these spots come with. I found several on Amazon.com, but I would need to know that the bulbs would focus narrow like the halogens do.

Not that I know anything about it but I don’t think an LED is going to focus any different than a halogen. Halogens are just brighter than a standard but don’t really focus any different than a standard bulb. You might be thinking of the high intensity lights that are more focused and very bright, but expensive. I’ve swapped LEDs in the house and the light pattern is the same as standard.

You should try a boat forum.
Or visit the websites of spotlight manufacturers. Specifically for marine applications.

Or the Sylvania website, looking for brighter replacements for your current bulb. Sylvania makes much brighter direct-fit bulbs for cars, the tradeoff being shorter rated operating hours. If there’s a brighter bulb made for your application, Sylvania will have it. And their site may even have a number you can call to help you with the selection.

The beam pattern is a reflection of the reflector and lens designs (sorry for the pun). Spotlight manufacturers will likely make a better lighting unit for your boat; all you need to do is visit their websites.

For the record, I could rattle off the differences between regular incandescent bulbs, quartz halogen bulbs, LEDs, and high intensity discharge bulbs. I could even link you to a site that compares spectral curves.But you can probably get better explanations off the Sylvania website.

It’s more than likely not going to work- here’s why:

The halogen bulb is a glass envelope that emits light into a 360 degree sphere. That means 50% of the emitted light is going backwards, away from the intended target. The answer to that is to place a reflector behind the lamp to collect all of this “unused” light and focus it forward into usable light.

An LED lamp emits light only in the forward direction.Therefore to focus the light, they use lens(es) placed in front of the emitter(s). Totally different design approach.

The LED cannot benefit from the reflector and the halogen based design does not have a lens at the front, only a flat piece of glass…therefore not interchangeable.

An LED lamp emits light only in the forward direction.Therefore to focus the light, they use lens(es) placed in front of the emitter(s).

Well, the Mag-Lite flashlight I’m holding in my hands has an LED bulb, no lens, a conventional looking reflector around it, and produces a tight spot of light. There’s more to it.

Interesting…perhaps they went so far as to mount the LEDs in a way to mimic the bulb so it was retrofittable. I’ll take a look and see what I can dig up but from what you said, it seems foregone conclusion that they may be making LED lamps specifically for retrofitting to older reflector designs. Thanks for the heads up!

EDIT: I forgot to mention, all of the LED flashlights I have are encapsulated LEDs (the tip is a lens) arranged in a pattern and facing forward through a flat glass disc…

I once bought an LED replacement for the common 2 D Cell flashlight bulb, but it did not focus. One good thing about a Maglite, you can adjust the focus. And I think that a few of the 12 Volt LED bulbs I saw on Amazon mentioned a 360 degree pattern. I will check that again though, to see if I remembered right.

OK, had a look see. They have two different versions I found;

First, a standard LED array mounted on a flat plane w/o lens. This has about 110 deg illumination angle. The reflector is capturing a portion of this wide angle dispersion for focusing.

The second is an encapsulated LED with traditional package including a lens at the tip. This lens is poking out the top of the carrier so it will fit into the traditional bulb holder. The lens is purposely diffusing the light so it can then be used with the reflector for focusing. These type of lenses can provide slightly greater angle to improve efficiency of the reflector but the total amount of light is the same.

Like I said the LEDs I’ve replaced in the house which are both lamp bulbs and can bulbs are imperceptible from standard bulbs once they are in the fixture. They emit light the same way as the standard bulbs. I even noticed some clear bulbs and some flicker bulbs that are LED and outside of a slightly different base, look the same as standard. I think they have come a long way. I’ve never had to fuss with the car LEDs so have no idea what they are like. They don’t burn out for years.

Here is a copy of an H3 12 volt LED bulb for sale on Amazon showing how it is said to have a 360 degree shine. But most of the customer reviews said it wasn’t very bright so I haven’t ordered it. It is possible to read this attachment if you click on it…