Tungsten to LED

[Smiffy]

Hi Guys:

 

I mentioned in Ynot's post here that I'm thinking about writing a Blog article on the impending death of Tungsten, and that I might seek some input from the forum here. So here we go...

 

I posit that many of us, myself included, are holding onto Tungsten for purely romantic rather than technical reasons.

 

Both Robert Juliat, and apparently now ETC are pushing an LED profile, and it really wasn't that long ago that LED's were only useful in LED Screens. It is clearly inevitable that in the not too distant future, the equivalent output of a 5Kw fresnel will probably be possible. By then, we will likely have no excuses for claiming that LED's are not up to the job.

 

So...

 

Are we as a community of Lighting Designers resisting the impending death of Tungsten for little more than the romantic notion that tungsten is better in terms of 'quality' of light?

 

Discuss...

 

 

Cheers

 

Smiffy

[musht]

If only it were really so, few years ago it was fibre optics, sulphur lamps , LEDs again....

 

Robert Juliat may indeed be pushing an LED profile, 85W max CRI 82, CRI and discontinuous also makes a difference to how gels look, deep reds may look a bit dim...

 

Was wanting to quote some numbers, because much as like and respect RJ , wasn`t hugely impressed with Aledin saw at PLASA, but unfortunately can`t seem to find any photometrics on the product page or in the PDFs

 

http://www.robertjuliat.fr/ProductsGB/ALEDIN_vGB.html

 

Real world efficiacy of LED sources tends to be quite a bit lower than manufacturers test conditions might sometimes suggest.

 

"impending death of Tungsten" probably said that when fluro was invented in the `30s ;-)

[peza2010]

I think one of the things at the minute is for the better LED lighting, you pay big bucks for and for a lot of us, it is just not a viable option at the moment. For example, when we talk about using led for white light, the same answer generally follows - that answer being that a decent, natural white with LED is certainly possible, but you will pay for it. So I think shelling out a lot of cash for LED to do white is unrealistic when you already have tungsten profiles in your stock.

 

 

Another issue is WHY? time and time again we read on the forum suggestions to use moving lights, or any other intelligent lighting when the same effect could be created with the use of a couple of generics. intelligent lighting is great, and can add something to a design,but more and more people almost discount generics because they have intelligent lighting to hand.

 

 

In the same light however, I think (as is already happening) is the industry as a whole will be forced more and more into a greener way of working, and of course LED's are the perfect solution to this. We are already seeing for example, venues banning the use of anything other than LED uplighting. Would they be doing this if LED's were not available? Im not sure.

[musht]

Photometrics of LED profiles are even rarer than LED profiles.

 

But Prism do publish some numbers for their Reveal Profile, 93 CRI is better than 82 of Aledin and the Reveal can change colour.

 

Is it sending tungsten for an early bath ,er...

 

http://www.prismprojection.com/Products/Profile/Reveal-Profile-Datasheet-April-2011-US.pdf

 

350W max pull, your not going to be running a rig of these off 2 AA batteries.

 

Comparing 26 degree Reveal Profile against 26 S4, adjusted to using 575/240 HPL, first link to the data sheet that came up

 

http://theatre.uwinnipeg.ca/download/lx/s4x26.pdf

 

At 15` S4 477fc RP (16.4`) 304fc

30` S4 119fc RP (32.8`) 76fc

 

LED washlights have less to contend with optically and the numbers stack up differently, but like Mark Twain, reports of the death of tungsten have been greatly exaggerated.

[Ynot]

Another issue is WHY? time and time again we read on the forum suggestions to use moving lights, or any other intelligent lighting when the same effect could be created with the use of a couple of generics. intelligent lighting is great, and can add something to a design,but more and more people almost discount generics because they have intelligent lighting to hand.

To answer this one, I'd say that due to the steep increase in output and efficiency of the LED variety, the mid to top range fixtures are finally starting to hold their own as being useful for actually lighting the stage, rather than just being pretty eye candy. This puts them, in my view, into the range of fixtures than could directly replace a generic lantern (or indeed several) for many applications.

 

For example, in my venue, as discussed in my LED topic, we've added a fair number of LEDs as side, top and cyc light. As a result we can get a very good wash of colour across the whole stage from the LEDs, and just use a handful of tungsten generics as fills and highlights. Because of this, I recently drastically reviewed my method of lighting shows here - in many ways for the better.

 

OK, we're a comparitively small stage, but if there's no top range LED kit out there that can't do the same for larger venues now, there WILL be soon, I'd say.

 

So no - I wouldn't class the current crop of decent quality LED gear as being in the same vein as movers - small venues and schools etc would be FAR better off investing in some half decent LED gear and I'd be more than happy to recommend the same where I have influence, whilst I'd advise strongly against movers.

[mark_s]

if there's no top range LED kit out there that can't do the same for larger venues now, there WILL be soon, I'd say.

 

Oh there is. 'Shrek', for example, on one of the West End's largest stages, has a fair few BB4 Washlights in the rig (IIRC). As does 'The Wizard of Oz'. LED is defintely finding its way into large-scale productions.

 

On a related note, I'm slightly puzzled by Stage Electric's approach to LED. It seems that they're holding back on investing in LED due to the pace at which the technology is improving. That's fair, but surely when people are specifying LED now, they're going to lose business? The range of LED equipment in their hire stock is virtually nonexistent.

 

intelligent lighting is great, and can add something to a design,but more and more people almost discount generics because they have intelligent lighting to hand.

 

I no doubt sound like a broken record by now, but I don't believe that intelligent lighting can 'add' anything to a design. You develop your ideas and concepts first, and only after that should you start looking at how it can be achieved practically. Having your design led by the choice of equipment available (or using equipment just because you have it) is not good!

 

(Of course everyone has their own way of approaching things, but I strongly believe that you should not be led or driven by the kit that you have available).

[lightide]

We have produced LED products about ten years. We feel that LEDs have became more popular and useful day by day. Now LED products are widely used for lighting, display, decoration and direction etc. LEDs have replaced more ane more products, such as LCD, Fluorescent and halogen etc.

 

We believe that LEDs will develop fastly in future.

[paulears]

That's hardly correct,is it?

LEDs have replaced more ane more products, such as LCD, Fluorescent and halogen etc.

LEDs are mainly in addition to,rather than replacement for. I think the comment about fluorescent is important - when tubes first became available everyone though them a panacea to all sorts of lighting problems. Kitchens had to have them, yet nobody actually liked the feel of the light - hard and bright. Now the trend towards multiple smaller light sources means flu lighting in homes has got less prominent.

 

LED will simply become another choice to make.

[adam2]

To the many good points made above, I would add that LED lighting is improving rapidly, whereas incandescent is a mature technology and unlikely to change much.

 

LED is already the best choice for some applications, and will become suited for more and more lighting needs.

I would therefore make the following suggestions.

 

For a venue already well equiped with incandescent lighting, dont rush to change anything, but be aware of the potential of LEDs if any new equipment is needed.

 

For a venue being refurbished, including rewiring. Ensure that ample numbers of hard power outlets and DMX circuits are provided to facilitate the future use of LEDs even if this is not the immediate intention.

 

For a venue with an insufficient rig of incandesant lanterns, keep these for open white and pastel shades, but dont buy any more.

Supplement with LEDs as budget allows.

 

For a new or completly rebuilt large venue, with opening a year or more away. Plan for mainly LED lighting. The savings in electrical infrastructure and air conditioning will be significant. DONT buy the lanterns until the final stage stage of the project, even in 12 months improvements are likely.

 

For very small installs in venues with very limited power and budget, I would go all LED simply because the whole lot can work from a single 13 amp socket.

[Ynot]

For very small installs in venues with very limited power and budget, I would go all LED simply because the whole lot can work from a single 13 amp socket.

Care is needed with statements like this - simply because some of the even half decent LED products can take a fair current draw.

[David A]

this explains why Leds have a long way to go, their colour is still not good, they are not available as fresnels or profiles at any sensible price and "budget" units are usually only inconsistent rgb and flickery at low level.

http://www.jands.com.au/support/product_support/lighting_technical_materials/what_to_look_for_when_judging_an_led_fixture146s_colour_mixing_capabilities133

[Ynot]

this explains why Leds have a long way to go, their colour is still not good, they are not available as fresnels or profiles at any sensible price and "budget" units are usually only inconsistent rgb and flickery at low level.

http://www.jands.com...capabilities133

Actually, no, I disagree with this.

My recent experience with the LEDs that we use, plus a couple of hire options belies both those statements.

 

Why is the colour 'not good'...?

I personally like the fact that particularly saturated colours in the units we have are nice, crisp and strong.

 

As for availability, whilst not a fresnel in the true sense, the wash I can get with my LEDs is quite impressive, and though not as cheap as a basic Par 56/64 LED can, the prices on them is far from exclusive - I'd call them a medium budget option.

 

As for flickering, our Chauvet Colorados don't have any bottom end flicker, neither do the ETC Seladors and the mac 101 movers I hired in a couple of months back also had none. There is a little bottom-end flicker on the LEDJ Omnis, but not nearly as noticeable as I've had with cheap fixtures.

 

Will it replace tungsten entirely? Not yet, and I doubt it will entirely at any stage. But as a tool in MY box, it's one that I'll be using all the time!

[Tomo]

Why is the colour 'not good'...?

I personally like the fact that particularly saturated colours in the units we have are nice, crisp and strong.

The 'common' RGB LED fixtures have always been very good at making 'pure' Primary Red, Green and Blue.

- Depending on the specific optics, other saturated colours are often less good, but they're usually there.

 

However, it's very hard to get pastels and a range of whites - the cheaper end generally doesn't even try, you can usually find one white but any others are obviously tinted green, blue or pink.

 

The "Amber" improves the saturates around yellow/orange quite a lot and makes some 'warm' whites available.

- The same way that RGB gives a lot of oddly-tinted whites.

(Note that there are a lot of different Ambers with varying bandwidths and centre wavelengths)

 

However, all this is only when looking directly at the LED (video wall/blinder) or lighting neutral colour materials (white/grey).

 

Now use this LED fixture to illuminate some real objects such as painted/natural material sets, people and costume.

 

Lit by RGB, people tend to look a bit 'fake' - 'plastic' or 'waxen'.

 

Adding in extra colours is the way to fill in the details that makes things look real.

 

- A White emitter added to RGB or RGBA does help with some pastels and whites, where the chosen white is bright enough to fill in the gaps. However, you've usually still got the problem of oddly-tinted white when you're away from the fixture's 'best' white point.

 

Taken all together, this does mean that there's not really such a thing as a 'perfect' LED fixture.

You'll need to choose the right one for the job at hand.

 

- The perfect fixture for one region of the visible gamut will have compromised somewhere else. The better the fixture the fewer compromises, but still...

[David A]

"As for flickering, our Chauvet Colorados don't have any bottom end flicker, neither do the ETC Seladors and the mac 101 movers I hired in a couple of months back also had none. There is a little bottom-end flicker on the LEDJ Omnis, but not nearly as noticeable as I've had with cheap fixtures."

 

hardly "budget" fixtures

[Ynot]

"As for flickering, our Chauvet Colorados don't have any bottom end flicker, neither do the ETC Seladors and the mac 101 movers I hired in a couple of months back also had none. There is a little bottom-end flicker on the LEDJ Omnis, but not nearly as noticeable as I've had with cheap fixtures."

 

hardly "budget" fixtures

Selador, no, they're upper mid range, but then I didn't say they WERE budget fixtures - I said they wer mid-range...

The Colorados can be gotten for around £275 if you have some buying power. The Omnis are under £200 each.

 

Now use this LED fixture to illuminate some real objects such as painted/natural material sets, people and costume.

 

Lit by RGB, people tend to look a bit 'fake' - 'plastic' or 'waxen'.

 

Adding in extra colours is the way to fill in the details that makes things look real.

 

- A White emitter added to RGB or RGBA does help with some pastels and whites, where the chosen white is bright enough to fill in the gaps. However, you've usually still got the problem of oddly-tinted white when you're away from the fixture's 'best' white point.

 

Taken all together, this does mean that there's not really such a thing as a 'perfect' LED fixture.

You'll need to choose the right one for the job at hand.

I wouldn't recommend anyone lights their whole stage with JUST LED, not at the moment anyway, which is why when our rig goes up after PAT and clean this month I'm rethinking the whole layout - using LED for colour on stage but allowing sectioned illumination of the stage with the existing tungstens (Parnel, Patt 223 etc) with a steel and straw plus 2 or 3 open lamps per area. That way we have enough pickup to cover the talent and/or set, there are lanterns available for any LD to spec their own choice if they wish, and the FoH gives plenty of front light and colour options as well.

 

It's all about using the tools in the box to their best effect, and in OUR case I believe that we've hit a good compromise of LED vs tungsten. For now.