~ How to Light Art ~

Most of us have woeful experiences to relate – awful LED lighting that washes out the colour in a painting and throws a ghostly grey/blue light. We also have cases of LED bulbs not lasting as long as promised, and of LED lights flickering, or simply not being bright enough.

But the answer is YES – now there are wonderful LED lights that have been developed especially for the lighting of beautiful things.

When lighting Art, nothing matters more than the quality of the light, so you need to look out for the following:

• Correlated Colour Temperature (CCT) of the LED: This is measured in Degrees Kelvin and denotes its ‘tonality’. For a traditional picture light, you should aim for a CCT of 2700⁰K, which will give you the kind of nice warm light you are used to from traditional incandescent or tungsten lamps. But be careful. Warmer LED lights are typically less efficient than the cooler, slightly bluer, ones, and you need to see that the light you are getting will be bright enough. If in doubt, do a test.

• Colour Rendering Index (CRI) of the LED: This is the most important consideration of all when lighting art, and denotes how uniformly distributed the white light delivery is across the full-colour spectrum, and how well that ratio is maintained over its life.

  It is only under a well-balanced, high CRI light that all the colours in your painting, especially red, will be properly reproduced. The best picture lights offer a CRI of 95 or more. The cheaper the LED, the less you can trust the CRI to be maintained over its life, or to be consistent from fixture to fixture if you are purchasing more than one.

  
  
  

The red colours in these two collections of paintings are represented richly under the very best quality of light.

What about heat and UV?

You are absolutely right to be concerned about such things.  Terrible, and largely irreversible, damage has been done in the past, with owners and curators having been simply unaware of the harmful effects these two invisible energies, jointly and severally, were having on their art collections. 

It is a widely-proclaimed, and dangerous, fallacy that LEDs don’t get hot. They do. The brighter they are, the hotter they run, and proper thermal management is very, very important.  Badly-managed LEDs will get too hot for their own comfort.  They then become ‘parasitic’ and consume more energy, thereby getting hotter and, by the same cycle, progressively hotter.  This will severely shorten their life and cause premature failure of your picture light. 

An LED system that is man enough to illuminate a reasonably-sized canvas will be packing some punch, so you should be sure that the picture light head has sufficient capacity to dissipate the heat generated. The good news is that, unlike traditional tungsten halogen lamps, any heat being emitted by the LED should be conducted backwards into the metal hardware of the picture light head rather than projecting forwards onto your painting, as had been the case in the past.

The other good news is that LEDs emit no harmful UV rays, either.  From an art-conservation point of view, therefore, you are on safe ground. But be careful about exposure to sunlight.  Lovely though it is, do not let this stream across walls that are hung with your precious paintings.

The use of variable lensing finally enables the whole canvas to be properly and evenly lit.

We are constantly amazed at how much the users of standard picture light products have learnt to put up with, meekly accepting as their lot the truly appalling lighting coverage these have traditionally given.  The actual term ‘picture light’ was really something of an oxymoron! Light heads were too small, the arms were too short, they often stuck out from bang on top of the picture frame and even obscured some of the picture, and the standard light bulbs benefitted from no optics at all.  What light there was just dumped onto the top of the painting.

Sometimes, this splodge of reflected light glared so badly that it almost completely obscured the image underneath.  And as for the rest of the canvas, what detail there was could hardly be discerned. Professional picture lights, using individual halogen lamps in varying numbers, have been around for a long time and these gave a far better light distribution across the canvas expanse.  These tended to be mainly on the radar of specialist Lighting Consultants, and not very many normal (of even slightly paranormal) households would think it necessary to seek the services of a ‘lighting consultant’ when looking to acquire a few picture lights! As yet there are no quality LED lamps available to replace the equivalent tungsten lamps, like for like.  However, if you are fortunate enough to be the owner of some of these fittings you are better placed than most, since the existing hardware can almost certainly be quite easily re-purposed by helpful fabricators, or even by your own handyman, to incorporate today’s new LED components.  

There will always be inexpensive off-the-shelf products that will deliver the same disappointing results as their predecessors.  In summary, there really is no need to suffer from badly-distributed light any more—so don’t!  Today’s mid- and top-of-the-range picture lights are fitted with LEDs which have been specially developed to project the light using a range of lenses with varying optical properties.  Some of these will be designed to spread the light broadly in the horizontal plane, across the width of the canvas;  others will be intended to  project the light in a stronger vertical axis, down the height of the picture.  The best of these picture lights will also have lensing that is tailored to suit the orientation of the canvas (for portrait or landscape). The very best will even feature optics that have been selected exactly to suit your particular painting — its shape as well as its overall size. 

The early claims of LED immortality (for expectations of 100,000+ hours) have long been exposed as complete Bunkum.

But they still do last a very long time (if properly thermally-managed), and you will not need to waste all that money replacing blown bulbs – or to navigate the inconveniences associated with so doing. Typically, you should expect to get 50,000 hours of light life before the LED loses more than 30% of its output – so, say, 15+ years of normal domestic use. That’s a fair old time for most of us to contemplate!

You may anticipate around 10% of these not lasting that long, so you should be cautious and perhaps even have a strategy – probably in the form of a few spare back-up lights – to manage the consequences of premature/rogue failure. In considering your options, bear in mind the following:

• For picture lights where the LEDs are built into the light head, the bad news is that the whole picture light will need to be replaced when an LED fails. When selecting a light which has been manufactured as a complete entity in this way, pay particular attention to the issue highlighted earlier of ‘thermal management’. Probe a bit into the optimum temperature operating conditions of the LEDs, and ask how the heat they generate is being directed away from the individual lamps. If you have confidence in the responses you get, you are probably safe to rely upon rogue failure occurring during the manufacturer’s warranty period – which is typically 3 years; and in which case the unit should be repaired or replaced free of charge. So potentially not too much to worry about, beyond just a bit of inconvenience.

• For picture lights where the LEDs are separate lamps or individual modules, you are on much safer ground. The LED lamp may be a market standard, in which case you can be pretty confident that major lamp manufacturers will continue to produce like-for-like alternatives as technology progresses. If the modules are a special-make, discuss the issue of future ‘re-lamping’ with your supplier and ask him to clarify his policy and plans for future iterations—bearing in mind that this LED technology is moving much faster than we are accustomed to for such things. You may want to hold a few individual LED modules in reserve in your cupboard – where, of course, you used to store your substantial maintenance hoard of incandescent and halogen replacement light bulbs; so not too much hardship in that.

• As an aside, in reality it is more likely to be failure of the driver at its end of life that will precede failure of the LED lamps. This will probably have been fixed separately to the back of your picture frame, so should be relatively easy to replace in due course.

Many picture light styles can be fitted onto either the picture frame, or the wall.

The former is the most common style for what might be considered a more ‘serious’ approach, since this enables an adjustable arm to be set in the correct position in relation to the canvas and to ensure the best lighting distribution has been achieved before the painting is re-hung. Of course, this approach does mean that the paintings will have to come off the wall – but they may need to in any event where the driver is also to be fitted onto the back of the frame.

It is helpful if your picture light supplier also offers an installation and commissioning service, since this means they will be able to help you where necessary, and will be familiar with the process.

It is helpful if your picture light supplier also offers an installation and commissioning service, since this means they will be able to help you where necessary, and will be familiar with the process.

If your paintings are exceptionally large or hung in particularly awkward places such as on a staircase, they can probably also introduce you to some specialist art handlers who have all the access apparatus needed and as much experience in such matters as you could ever want, as well as being comprehensively insured to carry out this kind of work.