Understanding LED lumen output vs. HID lamps

Relating output lumens of an LED bulb to an energy source is not an precise way of measuring effective light output of a fixture. HID lamp lumens are measured spherically, including all lumens produced over the entire 360 degrees off the bulb.

Most light fixtures have to redirect much of these lumens back down to the target area, losing as much as 50% of the illuminating power in the process.

LED luminaires provide directional light output and have practically zero wasted lumens. Virtually every LED lumen is directed and placed to maximize efficiency. A more accurate evaluation is to measure actual foot-candles or LUX on the ground. HPS and MH lamps have a substaintial initial light output loss within the first 6 months. LEDs have no such drop and deliver useful light [with only 30% depreciation] for 12 to 15 years before needing replacement.

Measuring light effectiveness: Photopic vs. Scotopic vision

‘Photopic lumens’ refers to the amount of light emitted from a light source as measured by a light meter. The typical light meter is most sensitive to the yellow-green part of the color band. This is the light that is seen by the cone receptors in the eye, the eye’s cone activated or photopic vision.”

“However, the rod receptors in the eye also receive light, called rod activated or scotopic vision. This light, which is rich in the blue portion of the spectrum, isn’t measured by the typical light meter. Therefore, until now, lighting manufacturers have only measured light output based on the eye’s sensitivity to one type of vision (photopic).”

“A true evaluation of lumen effectiveness comes from the combination of the light received by the rods and cones (photopic and scotopic); or ‘seeable lumens.’ Therefore, measuring only photopic lumens is misleading when comparing different colors of light. This is why even though a lower lumen reading is obtained with a LED vs. HPS or Metal Halide; the LED will produce more "seeable" light.

See Photometrics
for more information on light measurement and distribution.”


DIMMABLE from 0-100%

Unlike induction lighting or other HID technologies, our LED lights work beautifully with motion sensors; so when your lights are not needed -they don’t have to be on.
This further increases their lifespan and your energy savings.

Simply install motion sensors in areas which can get by with dimmer lighting when no one is there. When needed, motion sensors will turn the LED Retro-Fit Street™ on full strength instantly.


  • Slash Your Energy Costs: ENERGY SAVINGS OF 70-80% - over old HID technology & up to 44% over regular fluorescent.

  • MADE IN THE USA: RFS light units are manufactured and assembled in Colorado.

  • KEEP YOUR CURRENT FIXTURES: When you purchase our Retro-Fit system, your not paying extra for a new LED fixture, or paying extra for the labor to remove and replace your current fixtures; we feel you shouldn’t have to discard your perfectly usable fixtures in a land fill or metal yard to move to LED technology.  Reusing fixtures where possible helps the environment, and speeds up your Return Of Investment. Our RFS bulb and driver only replace your current HID bulb and ballast, and installing our system is as simple as a bulb and ballast change.

    (If new fixtures are needed, Level2Lighting™ also offers Universal fixtures, and we have the ability to design custom fixtures to meet special needs).

  • PRESERVE PROPERTY LIGHTING DESIGN: LED Retro-Fit Street™ system maintains the look and feel of your property and eliminates the upfront costs associated with other retrofits.

  • REDUCE MAINTENANCE COSTS: RFS lights are rated for over 8 years of continual usage, compared with a HID bulb or ballast which fail and need attention every 2 years or less.

    (Note: Most manufacturers judge replacement times by using the 70% rule; by this rule, our lights at 70,000 hrs or 8 years, will have dimmed 30% – at this point it is the LED chip manufacturers “recommendation” that the lights be replaced. However, in contrast to an HID bulb which burns out completely – leaving that area in the dark, an LED’s light output only dims over the life of the unit, until replacement is desirable. So the exact replacement time will need to be determined by each customer).

  • MERCURY AND UV FREE: Unlike all HID light sources mentioned above, RFS lights do not use mercury to produce light, so there is no threat of mercury gas or solids exposure and no need for a hazmat cleanup if a bulb is broken.

  • 100% RECYCLABLE or REFURBISHABLE: After our long LED lifespan, each of our units can be recycled, or refurbished again & again and placed back in service for a reduced cost over a new unit – Our drivers will last up to 3 LED Retro-Fit Street™ changes, (Driver life- span rated at 500,000 hrs!) – further reducing future relamping costs and unnecessary landfill waste.

  • INCREASED VISIBILITY/ INCREASED SAFETY: It’s your choice; we’re able to match or even raise your current light output and still slash your lighting energy expense by a large percentage.

  • INSTANT-ON Motion Sensor-Friendly: Temporary power outages happen and are a problem for HID lamps, which take 5-15 minutes to warm after each power interruption. RFS lights turn on instantly, so the second the power comes back up, your property will have full light.

Our HID LED bulbs are designed to be a direct, commercial grade, “retrofit” replacement for HID bulbs and ballasts: High Pressure Sodium, Mercury Vapor, and Metal Halide. Florescent lights can be replaced by including our fixture.

Ideal for street lights, parking lot lights, garage lighting, wall-packs, warehouse lighting, factories & canopy lighting.