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[Tim McCulloch]

30w led with a 4 deg beam versus a 60w led with 8 degree beam.

Tell me what information I'm missing to determine what I want to know.

The Password® is:  PHOTOMETRICS

[Dave Garoutte]

Those two beam specs are probably indicating a different intent.
Are you looking at aerial effects or stage lighting?
The tighter beam will probably be more effective with haze.
What are you trying to achieve?  More info needed.

[Dave Guilford]

Hi guys.  OP here.  Here's the info

Light Source: 1x 60W RGBW 4-in-1 LED
Beam Angle: 8°
Luminous Intensity: 
77,372 Lux @ 1M
15,330 Lux @ 2.5M
3,747 Lux @ 5M

And the other fixture...

Light Source: 1x 30W high-output white LED
Beam Angle: 4.7°
CCT = 6500K
Luminous Intensity:
63,163 Lux @ 1M
9,480 Lux @ 2.5M
2,185 Lux @ 5M

Will there be much of a difference in brightness, do we suspect?   Small stage use, approx 400 cap room.  I'm pretty confident either will be acceptable.  Just trying to learn. 

[Mark Cadwallader]

Yes. The 60w fixture is somewhat brighter, and certainly covers more area. How much area do you want illuminated?  More is not always desirable.

Tell us about how the fixture is being deployed, and how it is being used.

[Cailen Waddell]

That’s an awfully small beam for a 400 cap room unless you have 40’ or higher ceilings. 

For a room with a 14’ ceiling i recently had 80 degree downlight and 36 and 50 degree sides and front. 


Sent from my iPhone using Tapatalk

[TJ (Tom) Cornish]

That’s an awfully small beam for a 400 cap room unless you have 40’ or higher ceilings. 

For a room with a 14’ ceiling i recently had 80 degree downlight and 36 and 50 degree sides and front. 


Sent from my iPhone using Tapatalk

Ding ding ding.

Op, get out your protractor and draw out how big 4 degrees or 8 degrees are (or get out your scientific calculator and do tan(fixture angle)*throw distance to get your beam width).  Both are extremely narrow.   Most LED pars are around 20 degrees which is useful with a throw of at least 10’ illuminating one performer that doesn’t move much.  Anything narrower than 20 degrees is a specialty fixture that I doubt will be useful to you.

In other words, both of these fixtures are probably poor choices, no matter the brightness.

[TJ (Tom) Cornish]

  Two, wattage is power draw and not indicative of light output. 

I will disagree here.  For fixtures of any reasonably similar vintage, I would argue comparing power consumption is as good as any method for determining relative output between two fixtures (maybe not so good at determining absolute output), as there is so much fudge room with beam vs field definition, throw distance, and just plain lying spec sheets on cheap fixtures.   Fixtures within a couple model years of each other are going to use LED emitters that have similar efficacy, so generally a 100w fixture will produce more output than a 75w fixture, though as has been said elsewhere in this thread, that’s probably one of the less important metrics.  Beamwidth is where you start.

[David Allred]

Ding ding ding.

Op, get out your protractor and draw out how big 4 degrees or 8 degrees are (or get out your scientific calculator and do tan(fixture angle)*throw distance to get your beam width).  Both are extremely narrow.   Most LED pars are around 20 degrees which is useful with a throw of at least 10’ illuminating one performer that doesn’t move much.  Anything narrower than 20 degrees is a specialty fixture that I doubt will be useful to you.

In other words, both of these fixtures are probably poor choices, no matter the brightness.

Maybe this will help.  FYI If these are generic (Chinese fixtures) be wary of the beam angle spec.  I got some very small spots spec'd at 8 deg, but were measured to be 11 deg.

[Dave Guilford]

Hey guys.  OP here.

How come no one will answer my question (except Mark, and thank you).

Will there's be much of a noticeable difference between the two?

Not Chinese.  No need for protractor. 

I'm already good on deployment and how to utilize.  I'm not new to lighting nor dmx.  I'm new to specs on lights.

[TJ (Tom) Cornish]

How come no one will answer my question (except Mark, and thank you).

Because your question, at least without context as to what you're trying to do, seems like the wrong question.

I apologize for trying to help.

[ProSoundWeb Community]