Too much lighting choice? Let’s cut through the confusion

British Prime Minister Harold Macmillan made an optimistic speech in 1957 that “we have never had it so good” and the same can be said of lighting today!

With so much choice of technology (HMI, MSR, LED, COB, remote phosphor, fluorescence…) and then LED subdivisions of white light, bi-colour, RGB-WW and then considering variances of panel design including spot or Fresnel, the choice can genuinely be bewildering for any camera operator.

However, Eddie Dias of Pro Lighting Direct responded with my request for clarity with what sounds like a very brave and rather simplistic statement.  He claims that when renting or buying lighting the questions are always the same.

1. Suitability
2. Budget
3. Manpower
4. Storage
   
   That’s it!

Be clear about what you need to do and the choice of suitable fixtures narrows enormously.

Technology has also helped, since modern lights built with LED technology have made many lights smaller, lighter and more efficient. This has been dramatically advanced with ‘COB’ (Chip on Board) LED technology.

A COB is a type of LED light which are essentially an array of LED chips tightly packed together to act as a single lighting source. 
(For technos out there, LED pixels are apparently bonded to a substrate such as silicon carbide to look like a large patch of yellow). This effectively creates one large LED chip that has an excellent uniformity of brightness, which makes it brilliant for lighting. 

The advantages of this are clear, as you can pack more lighting punch into a smaller area and this makes COB fixtures as effective as traditional point sources using HMI or tungsten filaments.

Efficient lighting is obviously great for the environment, so in this article, I am concentrating on LEDs only, though traditional lighting fixtures will continue to have relevance for many years to come, provided you accept that you will use more power than is otherwise necessary.

When renting or buying lighting the questions are always the same – consider Suitability, Budget, Manpower, Storage. That’s It!

Eddie Dias, Prolighting Direct

Making comparisons

Cinematographers, of course, will want to compare modern fixtures with more traditional HMIs etc, so the first question is, ‘How do the new single colour COBs with a 1.2KW power draw compare with existing fixtures?’

Eddie believes that many of us are still conditioned in the ‘Old’ ways of lighting much the same way as we still refer to fuel economy in MPG and beer in Pints (!).  Both VMI and Pro Lighting Direct have measured the lighting output of the Nanlux Evoke 1.2 and found it to have a comparable output to a 2.5 HMI Fresnel or an ARRI M18 1.8KW MSR, so the measure of power draw does not really compare.

It is easy to see how comparing lights from different technologies can really be really quite confusing.

Don’t take just our word for it. Here is an independent YouTube test on the web comparing these lights.

Manufactures don’t make it easy for us either.  Understandably they are always innovating and with it, bringing new terms and acronyms which have important differences in capability and performance.

If we cast our minds back to the arrival of the first LEDs in the marketplace, they began with the simplest array – RGB. (Hey technos, you may be interested that ‘B’ in RGB is not actually ‘blue’ but in fact, indigo with an emitter typically with a frequency of 450nm.  Similar nuances exist with the other colours too but using the simpler RGB terminology is quite helpful here!). 

The common red, green, blue array is a good starting point, as it makes use of the three primary colours of light and introduces the concept of additive colour mixing instead of the more conventional subtractive mixing we were so familiar with when learning to paint at school. 

White Light LEDs

As such, the first fixtures were only capable of producing a single colour – either daylight (5600K) or tungsten (3200K).  These were quite limiting and lights had to be ‘tuned’ to produce these colours, since white light is not a colour that individual LEDs were originally capable of producing (techno speak – LEDs are narrow-band emitters). Therefore, each pixel colour needed to be used in combination to generate each hue of white.

Bi-Colour LEDs

It wasn’t too long before technology allowed LED fixtures to output light in both daylight (5600K) and tungsten (3200K) at the flick of a switch and everyone will remember the 1×1 bi-colour litepanels which changed everything and became enormously popular, extraordinarily quickly.

RGB-WW LEDS

Fast forward some years and lighting manufacturers introduced more complex LEDs incorporating many different hues of LEDs commonly referred to as RGB-WW fixtures.  In this technology, two out of every three LEDs are white and one is coloured. 

These complex fixtures often include LED emitters of amber, lime, cyan etc which are capable of outputting a vast range of colours and some even can produce a ‘deep red’, which is very impressive for stage lighting but are not much needed for TV production.

This development meant that for the first time, LED fixtures were capable of producing a massive array of colours and could accurately synthesise coloured gel output without any of the light loss associated with shining lights through coloured gels. 

This also removes the environmental cost of disposing of harmful gels which are no longer necessary when using this design of lighting – something that we are all happy about. 

The design of this COB incorporates two white LEDs for every three pixels, so it is easy to understand why two thirds of the light output is white only leaving just one third of light output to to be coloured.

So if RGB-WW LEDs do everything, then why do we need any other lights?

This is a very good question and one that I myself wasn’t clear about when I started investigating the sea-change of lighting technology which has emerged post-COVID.  The answer is actually quite nuanced.

If you consider that a bi-colour lamp will give about 50/50 output of daylight and tungsten light, then it is easy to understand why bi-colours are not as bright as single colour lights.  So whilst RBG-WW LED fixtures can produce a wide range of colours, there is a cost to be paid for this capability. 

Since only two thirds of the LED pixels produce white light, it is clear to appreciate that the white light that they do produce has a lower intensity compared with white-light fixtures.  The coloured light that they can generate is really very useful but it will necessarily have also a lower intensity than the white light produced.  

When you consider that the clever electronics to make this all possible is quite expensive (colour fixtures cost roughly double single-colour LED fixtures to buy/hire) and that single white-light LEDs are brighter for generating white light, the first real question for the cinematographer to answer is whether they actually need coloured light, or not!

I am told that new colour COBs are in development for release soon which use a new type of colour mixing LEDs which outperform the bi colours, but this technology is still in its infancy.

Our experience is that most DPs require lighting to be as bright as possible for the same reason as always – more light means a smaller aperture and a greater depth of field.  Cameras can work at a wide range of sensitivities but even the domestic market requires the very highest definition as they sit at home on their 75” TVs watching every tiny detail.  As I have already explained, for a given power draw, white-light LEDs are brighter than bi-colour or RGB-WW lights, so I think that you know where I am going with this…

An equestrian friend of mine once told me that different breeds of horses genuinely are better suited to different terrains (horses for courses!), so it seems that this is very much the case with lighting technology too.

Soft Light or Hard Light?

Lighting styles influence the design of light required. If you want hard shadows, then you need a direct source and direct sources can always be adapted. They can be softened with a soft box or dome or lantern, or used bare, with a fresnel or a profile lens. 

Mindful of this, I would suggest that a spot lighting ought to rate highly as a chosen option and be a preferred choice if an operator was looking to make a saving.

The examples below were shot by DP and photographer, Andrew Edgecumbe to demonstrate the importance of a strong key being used to create a large soft light. He used an Aputure LS300 inside a lantern hung by a Mega Boom Arm as a fill with the main key being punched through a 4×4 grid cloth (ARRI M18 MSR) or the large parabolic soft box (Nanlux Evoke 1200) as a comparison.

Some basic rules of lighting never change…

• The larger the softbox, the softer is the light output but also the stronger the light source needs to be.
• Softlights generally are only soft and cannot give a hard shadow but a soft light can save you time and space if this is the way you intend to light.
• Purpose made softlights are ‘Plug and Play’: plug them in and you already have a nice soft light which can then be controlled and softened further (using soft boxes and frames) and also dimmed. The soft light can be further controlled using of egg crates and honeycombs.
• …and if you are going to be using lamps in a studios or outdoor environment, then single colour lighting fixtures are likely to be preferred, as they will be most efficient.
• TV studios usually require a soft, even light for which soft LED Surfaces are perfect for. However, be aware that some of these units will require cooling, so be wary of noise generated from cooling fans.

Many hands make light work (literally!)

Depending on your needs you might just want to take dedicated soft lights for convenience but it is worth mentioning that you will need some hard lighting if you wish to create shape.  Obviously, the more fixtures and accessories you take, the more hands on set you are going to need to manoeuvre your kit!

The classic approach is a three light set up Fill, key and ¾ backlight so depending on time/ labour /budget, so choose your lights according to the size of your situation.

The classic approach is a three light set up Fill, key and ¾ backlight so depending on time/ labour /budget, so choose your lights according to the size of your situation.

Eddie Dias, Prolighting Direct

Power to the people

Because LEDs are so efficient, it is clear that they need less power than other technologies.  This fundamental truism meant that at least to begin with, early low power LEDs were easily powered from 12V camera batteries and lasted for a long time.  However, as the power output of LEDs has continued to increase, this assumption no longer always holds.

To put this in perspective, the earliest 1×1 LED litepanels drew just just 40W, whereas the largest Nanlux and Aputure COB LEDs now draw 1200W – some 30x more power, so you can be sure that a single camera battery won’t be strong enough to power it!

Higher power draw necessarily demands a higher current draw, so you have to be careful with battery and light selection to avoid damaging battery cells, since batteries only work within certain parameters and their life is greatly reduced if they are made to work too hard.

I don’t want to spend too long on this topic, as we are planning a separate article on this subject but the important point to explain here is that if you double the battery voltage to 26V, then the same current draw will deliver TWICE the power; then if you double the voltage again to 48V, then the the same current draw will deliver FOUR TIMES the original power.

This explains why the latest ARRI Alexa-35 cameras are designed to be exclusively 26V powerable, (instead of the conventional 12V), as the power demands of the latest cinema cameras are much higher than with previous models and the same is true of lighting technology too.

The conclusion here is that clients need to be aware that portable powering of very bright lighting may require greater consideration than in the past.

Weather Proofing

LEDs generally offer a degree of weather protection in their design. Many are IP65 rated, meaning that they can be safely be used in heavy rain (see rating definition), whereas conventional tungsten or HMI/MSR DEFINITELY cannot do this and require to be protected from the elements in order to work safely.

However, I would suggest that unless a given fixture is designed to be used in heavy rain (IP65), then treat them with respect and keep them dry avoiding rain where possible or make sure that they are protected. 

Eddie’s advice is to treat the LEDs as you would your iPad and you will be OK!

Very efficient Dimming Capability and Amazing Functionality

We all know that traditional tungsten fixtures can dim very easily. Simply reduce the power to the light and its output dims, however at low intensity, a bi product is that the colour temperature also warms. Whilst some DPs like this, recognise that it is a consequence of a fault in the technology.

HMIs have a dimming capability though this is quite limited.  When you switch them on, the lights take some time to ‘strike’ and they become brighter as they warm up before they can be confidently used.

LEDs however, are the KING of dimming and this is all thanks to very clever electronics.  It also means that you have control at your fingertips, as they dim from 0% to 100% power very smoothly and most offer some kind of DMX capability too. 

If you don’t need a full gaffer or lighting desk control, then consider that all Nanlux/Nanlight fixtures all share a protocol whereby up to 12 fixtures can be operated by a single remote control that fits into your hand, so it may be advantageous to keep all of your fixtures of the same brand to take advantage of this capability. 

Most LED now offer a range of effects as standard, Paparazzi, TV, welding, fireworks police ambulance are all available by activating some settings in the menu. 

In summary

There is a lot of talk about RGB-WW LEDs but 90% of the time it is not required, so concentrate on the 3500>5600 Kelvin fixtures for the majority of your lighting needs.  

However, do ensure that any lights that you use feature good colour rendering (CRI) as this is crucial for most cameras.  91>96 CRI is common on most professional systems as cheaper fixtures tend to have a green or magenta cast (which is why they are cheaper!).

In summary, be clear about your needs and use the right tools for the job!

You may be interested in our workshop and events programme. We are running a series of 3-hour in-person workshops will directly compare and contrast the latest generation of LED COB lights for busy producers and crew alike.

Credits:

Eddie Dias, Prolight Direct Ltd
Barry Bassett, VMI