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Alan B
03-22-2010, 12:19 PM
What lamp wattage and beam spread do you prefer for downlighting?

Assume that the fixture is mounted 25'+.

If there are variables such as I prefer X wattage and Y degrees for a natural moonlighting look, but A wattage and B degrees if the purpose is to illuminate and area for safety/security. Or if the purpose is to illuminate the tree the fixture is mounted in I use this, but if the purpose is to illuminate a larger area on the ground I use this ...please include that info.

Thanks!

Alan

emby
03-22-2010, 12:52 PM
What lamp wattage and beam spread do you prefer for downlighting?

Assume that the fixture is mounted 25'+.

If there are variables such as I prefer X wattage and Y degrees for a natural moonlighting look, but A wattage and B degrees if the purpose is to illuminate and area for safety/security. Or if the purpose is to illuminate the tree the fixture is mounted in I use this, but if the purpose is to illuminate a larger area on the ground I use this ...please include that info.

Thanks!

Alan

Alan,
I would prefer to use a mixture of 20-35 watt 60 degree lamps to illuminate a larger area on the ground. If you are illuminating a path then maybe up the lamp wattage to a 35.
If I were to design it so that the fixture is on an outer branch pointing towards and illuminating the lower tree trunk I would use a 20 watt 24-36degree spread.
This all depends on ambient light as well. If there is lots then 35 watters for sure. If there is no ambient light then all 20 watters except on the paths for safety.

My 2 cents.

Ken

Alan B
03-22-2010, 01:38 PM
Ken,

Thanks for feedback.

I was recommending 35w 36 degree as the bread an butter for most applications (I would like to suggest a 60 degree but felt the long shroud of most downlights would prevent the spread and eat up much of the lumens). I wanted to make sure I was giving good advice and that my own experience was correct.

I have never used a 50w, but didn't know if others did. Also didn't know if most used the 36 degree (due to glare guard) or if they used 60 degree.

Thanks for the input and look forward to some more perspectives.

Sincerely,

Alan

RLDesign
03-22-2010, 02:39 PM
Hello,

I have design with anything from 20-50 W, and a variety of beam and lenses. The 50 W has only come into play when I am trying to provide a zone of light for entertaining, and I usually am at an elevation of 30ft or higher. I overlap the circles of light and sometimes throw the frosted/spread lense in the mix to reduce the output and soften the edges. I almost always have those on a dimmer to allow for the correct adjustment to fit the mood. In tree downlights, mostly I have been installing 20-35W.

I hope this helps.

Tanek
Reynolds Lighting

Alan B
03-22-2010, 02:46 PM
Tanek,

Thanks for the info.

Cheers,

Alan

The Lighting Geek
03-22-2010, 07:46 PM
Most of the time I use 20watt BAB 38 degree, sometimes a 60 degree. If I am using a 35watt it is to compensate for a fixture mounted higher in the tree so the intensity remains even on the ground. I generally use a frosted lens as well.

Lite4
03-22-2010, 08:33 PM
Generally from 25' or higher I will use a 35 watt FMW, and lower will use a 20 watt BAB. Just depends on what is on the ground that I am highlighting and ambient light levels. I always knock out the front glass on the fixture (if it has any) and silicone in a honeycomb louver to allow any moisture to pass out of the fixture freely. .02

Alan B
03-22-2010, 09:47 PM
Tim,

Great tip about the knocking out lens and adding honeycomb louver.

We are re-designing the Top Dog fixture for downlight specific applications-- possibly we'll use your advice and make the fixtures with no lens and a honeycomb louver instead. When i think about it .. it's a great idea. I don't see why the lens is needed when it will be aimed down, it will keep all condensation,moisture out and possibly help LED retrofits dissipate heat by not keeping the heat trapped inside a sealed fixture.

We already silicon seal where the wires leave the fixture but it's still possible for water to seep thru the knuckle and into the fixture over time. Accordingly we were going to also silicon seal the inside of the body where the lead wires enter the body-- but I like Tim's idea better--guarantees no water inside the fixture, plus adds the benefit of louvers.

Anyone see an issue buying a downlight specific fixture this way --no lens and instead have open louvers? What are your thoughts?

Tim, thank you for the advice.:clapping:

Sincerely,

Alan

INTEGRA Bespoke Lighting
03-22-2010, 11:34 PM
I will go out on a limb here (pun intended) and suggest that I have more tree mounted downlights installed than any other contractor who participates on this forum.

I have tried so many fixtures for this application it would make your head spin. For the most part they ALL have failed for one reason or another. The CAST Treelight CCTL1C is the best product I have found yet.

Alan, I would strongly recommend you do not remove the lens from your planned tree light. Around these parts we cannot use an open fixture as we get all sorts of bugs, esp. catapillars, moths, and other cocoon type insects that love to establish themselves in the fixture / shroud if they can. Also, if someone wants to use LED MR16 lamps in the fixtures they really need to be kept as dry as possible. An open fixture will allow rain / snow that is whipped up by the wind to contact the lamps. (this will also shorten the life of Halogens)

As for lamps, I have only used 35W FMW on a couple of occasions when the ambient light dictated the need for a brighter effect. 20W BAB and 3000K45 Deg LED MR16s are my lamp of choice for over 95% of my installed fixtures.

Remember guys... "the higher the light the closer to God" I try to stay above 30 feet always.

If you would like to pick my brain on your new fixture, give me a call when I get back to my office.

JoeyD
03-23-2010, 10:55 AM
Tim,

Great tip about the knocking out lens and adding honeycomb louver.

We are re-designing the Top Dog fixture for downlight specific applications-- possibly we'll use your advice and make the fixtures with no lens and a honeycomb louver instead. When i think about it .. it's a great idea. I don't see why the lens is needed when it will be aimed down, it will keep all condensation,moisture out and possibly help LED retrofits dissipate heat by not keeping the heat trapped inside a sealed fixture.

We already silicon seal where the wires leave the fixture but it's still possible for water to seep thru the knuckle and into the fixture over time. Accordingly we were going to also silicon seal the inside of the body where the lead wires enter the body-- but I like Tim's idea better--guarantees no water inside the fixture, plus adds the benefit of louvers.

Anyone see an issue buying a downlight specific fixture this way --no lens and instead have open louvers? What are your thoughts?

Tim, thank you for the advice.:clapping:

Sincerely,

Alan


All of our down lights are buiilt that way for that reason. Heavy snow drifts can blow snow up the shroud but the lamp tends to melt it away. We rarely see any issues with our down light fixtures.

INTEGRA Bespoke Lighting
03-23-2010, 05:24 PM
Send me a bunch of them for installation up here Joey, I will document how they perform and send them back to you for evaluation if/when they fail.

Open fixtures are the stuff of the 70's and 80's. We should be pushing for more IP rated fixtures for all applications, then there would be no question as to a fixture's effectiveness and longevity no matter what environment it is installed in.

IP Ratings are going to be the next big thing in LV outdoor lighting fixtures, watch and see.

The Lighting Geek
03-23-2010, 05:55 PM
I am probably going sound stupid, but what is an IP rating?

INTEGRA Bespoke Lighting
03-23-2010, 06:05 PM
Ingress Protection Ratings.

http://www.engineeringtoolbox.com/ip-ingress-protection-d_452.html

Some of the better manufacturers already submit their products for IP certification. I am working with a new manufacturer who is committed to producing only IP65+ rated fixtures in all configurations.

extlights
03-23-2010, 06:07 PM
IP rating is an International (ingress) Protection rating. It works off of codes basically. There will be a rating that says IP and then 2 numbers after it. Each number of the code represents a certain protection that pertains to the ratings.

JoeyD
03-23-2010, 06:44 PM
Send me a bunch of them for installation up here Joey, I will document how they perform and send them back to you for evaluation if/when they fail.

Open fixtures are the stuff of the 70's and 80's. We should be pushing for more IP rated fixtures for all applications, then there would be no question as to a fixture's effectiveness and longevity no matter what environment it is installed in.

IP Ratings are going to be the next big thing in LV outdoor lighting fixtures, watch and see.

How many lights you want James? 100, 200? :laugh:

INTEGRA Bespoke Lighting
03-24-2010, 01:42 AM
How many lights you want James? 100, 200? :laugh:

No Joey, I think 10 would do. I will install them in the woods behind my home. When the forest tent caterpillars and moths and such build their cocoons inside the fixtures, and when the rain and snow whips up into the exposed lamps causing them to fail prematurely, I will take close up photos and then send them back to you.

Open fixtures are no joke when it comes to longevity. Everything inside takes a beating over time.