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View Full Version : How high can an MR16 light?


starry night
04-14-2012, 03:45 PM
Can I effectively light to the top of this steeple (the stone part) with an MR16?

Lite4
04-14-2012, 05:44 PM
Phil,
It depends on the brightness you require. If I was choosing an Mr16, I would look at a 20 watt BBF. I know your saying, a 20 watt? Seriously!? Check out the photometrics, it will blow you away how intense the output is in those babies. Comparable, if not better than a 50 watt equivelant. If they are wanting greater illumination though, your really looking at a 75-150 watt MH

starry night
04-14-2012, 06:08 PM
Hello Tim, Thanks. I'm still trying to learn some of the terminology on bulbs.
Not sure about the designations like BBF, ESX, etc. Is there a list somewhere?
Also a supplier for BBF? Appreciate your help (and everyone on the forum on other questions.) I was able to land a 3/4 page newspaper article about my business startup and have had several calls from that.

Lite4
04-14-2012, 08:50 PM
Phil, you can go on Ushio's website. They have all the photometric data listed there. The BBF is 24 degree lamp and will easily poke up to the top of that church tower if there is not a lot of other ambient light from streetlights. Look at the initial candlepower and then the foot candles at 20'+, I am not a huge Ushio proponent, but the optics on this lamp is impressive. No LED in the same class will touch it.

steveparrott
04-15-2012, 11:21 AM
Phil,

Most photometric charts don't extend so high, so I created one for this type of job: download chart (http://www.cast-lighting.com/calculator/beam-combo2.pdf).

Don't know your steeple height and width, but it looks like you might needs a 12 degree.

To calculate the footcandles, use the formula:
Center Beam Candle Power (CBCP) divided by distance squared.

Typical CBCP for MR-16 lamps:

20W, 12 degree: 3,300
20W, 24 degree: 1,400
35W, 12 degree: 6,100
35W, 24 degree: 2,500
50W, 12 degree: 9,000
50W, 24 degree: 3,000

Your target footcandles depend primarily on ambient light and other illuminated objects nearby (including the tower beneath). It also depends on the specularity and color of the roof, and on whether or not you want this roof to be a visual destination (probably do). I would say your target range is 5 to 10 fc.

With that in mind, you might want to really punch the light - 50W, 12 degree or, preferrably, (2) fixtures 35W, 12 degree.

starry night
04-15-2012, 11:53 AM
Thanks Steve, That info and the photometric charts are very, very helpful. I know I will be using them frequently for reference.

starry night
04-15-2012, 12:10 PM
Look at how interesting the entrance to this old church is. The stonework is amazing. Unfortunately, they don't have much money to work with for this project or it could be fantastic.

steveparrott
04-15-2012, 12:13 PM
Look at how interesting the entrance to this old church is. The stonework is amazing. Unfortunately, they don't have much money to work with for this project or it could be fantastic.

Any way you could give them a special deal, or invite contributors to fully illuminate the church? This could be a signature project for your business - the photos would be spectacular!

David Gretzmier
04-18-2012, 09:42 PM
your cost of some wire and a few added fixtures might be recovered through advertising on the corner with a 3x5 sign for a few months. "Landscape lighting provided by"... "phone number".

you also might donate your labor and have them buy the materials, and see if the local newspaper or TV will run a story to go along with the sign.

we get jobs from signs all the time, just a thought.

Richie@
04-19-2012, 06:24 AM
Look at how interesting the entrance to this old church is. The stonework is amazing. Unfortunately, they don't have much money to work with for this project or it could be fantastic.

Beautiful entry way , you could design it for them an do a 3-4 part payment plan for them on just the entry way , this way helps the church and gives you a show piece.

It's a no brainier in my opinion.