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View Full Version : Photometrics-Lumens Who uses them?


JoeyD
01-08-2008, 11:19 PM
I was curious what everyones take was on their use of lamp and fixture phtometrics. Do you use them when working the spacing of a pathway or wall lighting application during the design phase, or do you just sort of wing it with an educated decision based of of experience?

And as for Lumens I know that lighting projects such as Dark Sky and commercial hotels and hospitals will require maximum and minimum Lumen outputs. But how many of you have ever ran into this, and if you did how did you obtain your Lumen information?

Joey D.

INTEGRA Bespoke Lighting
01-08-2008, 11:29 PM
I was curious what everyones take was on their use of lamp and fixture phtometrics. Do you use them when working the spacing of a pathway or wall lighting application during the design phase, or do you just sort of wing it with an educated decision based of of experience?

And as for Lumens I know that lighting projects such as Dark Sky and commercial hotels and hospitals will require maximum and minimum Lumen outputs. But how many of you have ever ran into this, and if you did how did you obtain your Lumen information?

Joey D.

The short answer from my end is: "it all depends"

Generally on residential outdoor systems I do not regularly use fixture photometrics. I will look at them for any fixture that I have never installed before just to ensure I understand what I will be getting before the installation.

Where I do use photometrics extensively is in commercial interiors and residential interiors. This is where you really need to understand the photometrics of the lamps you are choosing as well as reflectivity, opacity, beam spread, intensity, colour, etc etc. Generally I rely on lamp photometrics for these applications.

As for lumen output measures... I run into this when working with the municipalities and other groups when consulting on large scale civic issues. I also am asked to do "peer reviews" of proposed and built commercial outdoor lighting systems and I have to prepare reports citing the design capacity of the luminaires as well as actual recorded footcandle/lux measurements on site.

Hope this helps you a bit.

Lite4
01-08-2008, 11:42 PM
I refer to them when lighting something unusual, or if I am trying to constrain or maximize light for a certain application. When I start getting into different wattages I will compare the lumen outputs and spreads between bulb types and will pick a fixture to go with the bulb I choose for that application. I have always used the photometric charts in the back of the Vista catalog.

JoeyD
01-09-2008, 09:14 AM
Thanks guys! I hope to see more responses here.

irrig8r
01-09-2008, 09:54 AM
Once I get to know a fixture and lamp combination I'm less likely to look at the charts. When evaluating a fixture or lamp that's new to me, comparing them to what I currently use, or trying to pick a fixture for a challenging situation or interesting effect, I do use them if only to sort the "maybes" from the "no ways" before trying them out in the field...