Lighting Technology ReviewMetal Halide, LED & CDM

Light Source Advantages Disadvantages

1,000W Metal Halide Good coverage Low initial cost Been in use for over 40 years

Fragile and relatively expensive bulbs Inefficient by modern standards Low CRI (Colour Rendition Index) starting at around 64/100) Intense glare Flicker from bulbs Re-strike time

400W Metal Halide 55% saving over 1,000W All of the above plus:

Less coverage150W Metal Halide 75% saving over 1,000W All of the above plus:

Even less coverage

Metal Halide has now reached the end of its useful life for use in lighting towers.

Metal Halide lighting towers are low in cost but have an expensive upkeep due to frequent bulb changes and higher fuel consumption.

Metal Halide

Advantages Disadvantages

Good coverage More efficient than Metal

Halide Long life Not prone to blowing Instant on/off, no re-strike time No flicker

Still very expensive Intense glare Light produces at the blue end of

the spectrum Lower Colour Rendition Index than

CDM Still not as efficient as CDM

LED is becoming a more mature technology with efficiency, and light to power ratios improving.

Cost has also significantly fallen in recent years although LED still has the highest initial purchase cost.

The “penetration” of LED light is still not as good per Watt as CDM and therefore requires higher wattage LED’s to act as a replacement.

To replace a 1,000W Metal Halide 250W will usually have to be used.

150W LED’s are available but will not replace 1,000W Metal Halide on a one for one basis.

The light produced is also very Blue, creating glare and discolouration.

LED

Advantages Disadvantages

Good coverage Very efficient (95% light to heat) Natural daylight No flicker Low cost bulbs Tough bulbs (no filament) 12-15,000

hours Very high Colour Rendition (96/100 CRI)

Re-strike timeCDM is very cheap to run and provides the best quality of light, with the highest Colour Rendition (96/100).

It is also the most energy efficient with 150W directly replacing 1,000W metal Halide.

CDM

250W LED 150W CDM400W Metal Halide

Colour RenditionGravel Visual

Yellow discolouration Blue discolouration True colour

Mesopic Light & Colour Rendition

LED CDMMetal Halide

Photopic, Scotopic & Mesopic Light

There are three types of light when looking at lighting towers…

Photopic: Vision under well-lit conditions, which provides full colour perception, and which functions primarily due to cone cells in the eye.

Scotopic: Monochromatic (black and white) vision in very low light, which functions primarily due to rod cells in the eye.

Mesopic: A combination of Photopic and Scotopic in low lighting, which functions due to a combination of rod and cone cells in the eye.

Metal Halide and LED produce only photopic light.

The type of light produced by CDM is called Scotopically enhanced, broad spectrum light, otherwise known as Mesopic light.

Photopic, Scotopic & Mesopic Light

Traditional Metal Halide & LED produce Photopic light. This light has the appearance of being very bright by reproducing the same spectrum of light that is produced by the sun and stimulates one of two types of light receptors in the eye (Cones).

This creates a conflict between perceived brightness and actual visibility forcing the eye to switch between daylight and low light functions, significantly reducing visibility.

The Ecolite produces Mesopic light that is detected by both types of receptor in the eye, Rods and Cones. The stimulation of the Rods enhances light sensitivity, visual acuity and driver/operator reaction times.

By complimenting how the eye naturally works under low light conditions eye strain, headaches and fatigue are also eliminated.

How Mesopic Light Works

Photopic Scotopic Mesopic

Lenses Systems

95% of light is refracted through the prismatic lens into a known pattern.

“Hot spots” and fade out areas are eliminated, allowing the operator to illuminate a very specific area with ease whilst reducing light pollution.

As an equal amount of light is refracted through each individual prism, light arrives at the same destination whilst travelling from multiple angles significantly reducing shadows.

As large, dark shadows are not cast across the illuminated area, overall visibility is improved and the need to reposition lights reduced.

Colour Rendition Index

Colour Rendition Index is a quantitative measure of the ability of a light source to reproduce the colours of various objects faithfully in comparison with an ideal or natural light source.

Ecolite produces a CRI rating of 96/100, where as traditional Metal Halide has a rating of around 64/100.

Ecolite provides the best colour rendering of any lighting tower on the market.

1,000W MH - Photopic

CDM - Mesopic

4 x 1,000W MH Vs. CDM Glare Comparison

Metal Halide Glare (this also applies to LED)

CDM – Reduced Glare improved visibility

We are happy to prove this with night time demonstrations against any other machine on the market.

Health & Safety

There are several lighting hazards in the workplace which can affect the health and safety of people. Typical risks from

lighting originate from

-Lighting At Work HSG38

“ ”

1,000W MH Are Hazardous for Health & Safety

Glare happens where vision is not directly impaired but there is discomfort, annoyance, irritability or distraction the condition is called discomfort glare. The latter is related to symptoms of visual fatigue. Both types of glare can arise from the same source.

A surface lit by different artificial light sources, or by daylight under changing sky conditions, may appear to vary in colour. Where colour discrimination is required (as for some electrical work) this can affect safety.

The eye is particularly sensitive to flicker and it is especially detectable at the edges of the visual system’s field of view. Flicker can, depending on individual sensitivity, be a source of both discomfort and fatigue. It may even cause epileptic seizures in some people.

Some lamp designs also produce significant emissions at infrared and ultraviolet wavelengths, both of which are invisible . These can cause significant disruption to nocturnal wildlife such as bats.

Ecolite: Health & Safety

Prismatic lens and fewer photopic lumens reduces glare. Limited Glare Rating (LGR) down to 15 is achievable

Colour rendition of 96/100 compared to >64/100 for 1,000W metal halide

Combination of electronic ballast and CDM light source prevents any flicker.

UV blocked to prevent light pollution

CDM are superior to LED and Metal Halide because they are…

More efficient – Giving maximum fuel economyHave higher Colour RenditionHave Patented Prismatic Lens dramatically reduces glareUV blockedNo FlickerCheaper life time costsDirect replacement for 1,000W Metal Halide

To Summarise…

Contact Us

Contact Ross Dryden for more information on Lighting Technology!

Tel: 01621 745 747Mobile: 07712 135 842

Email: rdryden@youngmangroup.com