THE GREAT LIGHTS TEST

Just how bright are the different types of bike light? That question was the trigger for members of YACF (Yet Another Cycling Forum) to conduct their own investigation. Charlotte Barnes and Graham Glen report.

THE plan was to get a bunch of lights together, battery and dynamo powered, LED and incandescent, from across the price scale, to see how they performed. How hard could it be? Between us we came up with a total of 17 lights to compare. The lights were to be tested both indoors, to allow the light output to be measured and to compare beam shapes, and outdoors to see how they performed in ‘real world’ conditions. The battery powered lights all had freshly charged batteries. For the dynamo lights, to ensure consistency Charlotte mounted them all on her bike which is equipped with a SON hub dynamo. This bike was then put onto a set of rollers and pedalled up to a constant 15 mph (25 km/h). As you can see from the photo, this was a nerve wracking proposition! Outdoors, when the rollers and tyres were wet, was even scarier… For the indoors testing, the lights were shone along the length of our ‘secret bunker’ onto a target on the end wall about 5 m away. The outer ring on the target was 2 m in diameter. Then the following process was carried out for each light in turn: 1. A light reading was taken in the centre of the beam, and another at one metre from the centre. For the incandescent lights this was taken horizontally, and for the LEDs either horizontally or vertically as their beam patterns tended to be more even. The light meter was set to display EV values, so the reading increased by one for each doubling of the measured light. I then converted these to absolute values to allow the output of the lights to be more easily compared. 2. A picture was taken of the target (obviously lit only by the light under test) with the camera set to auto. It was hoped that when these pictures

were put together they would all be roughly the same brightness so that the beam patterns could be compared. 3. A picture was taken of the target with the camera set to manual exposure. We hoped that this would allow us to easily compare the brightness of each light. Once the indoor test had been completed, and without pausing to even drink a cup of tea or scoff any Jaffa cakes, the bikes were loaded up and a convoy set off (complete with rollers) for the local park where we set up to take more pictures. The lights were all aimed along the path, which was nice and dark to simulate the road, at a point about 20 metres away. A little past that point we put a Brompton as an example of a real world object which would refl ect some light. Again, two pictures were taken, one on auto to compare beam patterns, and the other on manual with consistent settings between tests to compare brightness. Although the lights could be easily aimed at the target indoors, outdoors it wasn’t as simple. Because most of the lights didn’t have a clearly defi ned centre spot (if they did, they would probably be useless as bicycle lights) they were aimed to try and maximise the amount of path that they lit up, including the aiming point. For the outdoor pictures the camera was set to its maximum sensitivity to reduce exposure time. That made the pictures a bit grainy, but not so much that it caused problems.

CONCLUSIONS Some interesting results here. The hub dynamo lights, even the very reasonably priced IQ Fly and Cyo models, exceed all but the most ‘serious’ (expensive) battery lights in centre brightness at least. The

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VELOVISION ISSUE 32 DECEMBER 2008

fearsome Lupine Betty does eclipse the rest of course, as it should for £700… The real surprise for us was that the Smart rechargeable lights were so bright in the centre of the beam. They’re the ones which bike shops used to knock out for around £35, with two incandescent lamps and a lead acid battery. We only put them in the test as a reference point, but it would appear that battery

powered incandescent lights are still pretty good. I wish we’d managed to get some Lumicycle halogens (or HID lights) into the line-up because based on what we’ve seen here, they might well still be the kings of sheer output. Note we didn’t test for overall light output, nor for run-time, nor brightness-to-weight ratios... So please don’t take these fi nding as defi nitive – more an illustration of what can be done with a bit of DIY effort. But we hope the results, and fi ndings on beam shape, are useful nonetheless. Many thanks to all who helped in the test!

Charlotte Barnes and Graham Glen

YACF: see www.yacf.co.uk Photographers: Jonathan Glen, Graham Glen

THE LIGHTS Seven dynamo lights and ten battery models:

Name

B&M IQ Fly B&M IQ Cyo Schmidt E6 Inoled Extreme Schmidt Edelux Supernova E3 Solidlights 1203D

Power Source

Dynamo Dynamo Dynamo Dynamo Dynamo Dynamo Dynamo

Lamp type

LED LED Halogen LED LED LED LED

Approx price

£ 60 £ 65 £ 65 £ 74 £ 90 £ 125 £ 155

Source/website

Most dealers Available in UK soon. www.nabendynamo.de www.inoled.com www.nabendynamo.de www.supernovalights.de www.solidlights.co.uk

Notes

60 Lumens version Various UK dealers From Germany Various UK dealers Symmetrical beam

Bikehut 3 LED Cateye EL-410 Smart Fenix L2D Hope LED1 Dinotte 200L Li-Ion Airbike Use Exposure Race Maxx Dinotte 600L Lupine Betty 14

Battery Battery Battery Battery Battery Battery Battery Battery Battery Battery

LED LED Halogen LED LED LED LED LED LED LED

£ 19 £ 30 £ 35 £ 39 £ 79 £ 120 £ 137 £ 230 £ 267 £ 700 (!)

Halfords Most dealers or www.cateye.com –www.fenixlight.com www.hopegb.com www.dinottelighting.com www.on-one-shop.co.uk www.exposurelights.com www.dinottelighting.com www.lupine.de

Discontinued

USA

USA Various UK dealers

BRIGHTNESS MEASUREMENTS Brightness comparison on/off centre:

B&M IQ Fly: £60

B&M IQ Cyo : £65

Schmidt E6: £65

Inoled Extreme: £74

Schmidt Edelux: £90

Supernova E3: £125

Solidlights 1203D: £155

Bikehut 3 LED: £19

Cateye EL-410: £30

Smart twin halogen: £35

Fenix L2D: £39

Hope LED1: £79

Dinotte 200L Li-Ion: £120

Airbike SL1: £137

Exposure Race Maxx: £230

Dinotte 600L: £267

Lupine Betty 7: £700

Centre

1m off-centre B&M IQ Fly

INDOOR TESTS

B&M IQ Cyo

Schmidt E6

Inoled Extreme

Schmidt Edelux

Supernova E3

Solidlights 1203D

Bikehut 3 LED

Cateye EL-410

Above: auto (to show beam shape) Below: manual (for brightness comparison)

Smart

Fenix L2D

Hope LED1

Dinotte 200L Li-Ion

Airbike

Use Exposure Race Maxx

Dinotte 600L

Lupine Betty 14

OUTDOOR TESTS

Above: auto (to show beam shape) Below: manual (for brightness comparison)

ISSUE 32 DECEMBER 2008 VELOVISION

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