Fixture question

Discussion in 'Landscape Lighting' started by Rainman7, Nov 17, 2010.

  1. Rainman7

    Rainman7 LawnSite Senior Member
    from NY
    Messages: 291

    I have a question regarding different manufacturers bullet lights. Some bullets like cast or unique use a spring loaded socket that pushes the light to the front of the fixture unless its a Lunar...I believe cast treelighter still uses the spring. Others have the socket mounted at the back of the fixture.

    I used some Encore fixtures and questioned the rep about different beam spreads and how if the bulb is mounted at the back of the fixture would I be able to achieve the stated beam spreads. He told me it would not make a difference.

    I look at it as the shotgun I wrong??? Will a 60deg bulb do its job from the back of the fixture? or will it be restricted by the fixture diameter?

    I'm not saying anything bad about Encore....Alliance, ABR, Volt all use the same mounting.
  2. Pro-Scapes

    Pro-Scapes LawnSite Platinum Member
    Messages: 4,180

    Different fixtures can certainly have an effect on photometrics of a given lamp.

    Your question of floating vs fixed cannot be answered. While alot of people preffer a fixed socket there are I am sure some who either dont care or are happy with the floaters. Once I went to fixed I never looked back. A more important factor in figuring out the answer to your question is how wide is the fixture? How deep regressed inside is the lamp? how long is the shroud ?

    The Lunar you mentioned will most certainly clip off a 60 degree lamp. More so than the similar but shorter Quasar 1 fixture especially due to the Louver tucked in the nose of the fixture. These offer superior direct glare protection but at the same time can narrow down most anything in the WFL catagory of lamp.

    You should experiment at your own home sometime. Place a fixture with no shroud or just leave the top off and see what a 60 degree lamp does. Then place the shroud on and note the difference. Try this same test with a 36 degree lamp and see if it still clips the beam down. This is why we need different fixtures for different situations. It is important to know how the fixtures you choose will perform with the intended lamp. If you dont follow me just try to put that 60 degree lamp in a Lunar.

    Your correct in thinking that a 60 degree lamp sitting in the back of a long narrow fixture will in fact be clipped off in many cases. The fixtures I use come standard with a hex louver right behind the lens that is pretty close to the lamp. Not all fixed socket fixtures are deep.
    Last edited: Nov 17, 2010
  3. David Gretzmier

    David Gretzmier LawnSite Gold Member
    Messages: 3,646

    agreed on all accounts with proscapes, and floating sockets also seem to be disappearing. I know that FX still uses them, but most don't. very deep fixtures also seem to be far between these days, but probably more becasue the cost of brass and copper rather than by design. a fixture whose bulb is fairly close to the lens will perform more like the bulb was intended. hex louvers also change beam spreads a bit, along with a slight drop in output as well.
  4. Pro-Scapes

    Pro-Scapes LawnSite Platinum Member
    Messages: 4,180

    Kets not forget the lens it self can also slightly modify output. Cheap lenses or convex lenses on a wall are really noticable to me.
  5. Alan B

    Alan B Sponsor
    Male, from tampa, fl
    Messages: 447

    Once again Billy is exactly right. I would like to add some other detail:

    1. The important aspect is how close is the front of the lamp to the lens (and how wide is the fixture). If it is recessed/sunken the fixture will block some of the wide beam spreads, and in case this effect can be a significant negative. However if it is too close you cannot fit lenses.

    2. One solution is the spring loaded socket or floating socket. It keeps the lamp close to the lens for full photometrics of the intended lamp and enables lenses. The down fall is:
    a. they are a pain to re-lamp, especially if the socket falls down inside the spring,
    b. they look unsightly/unfinished,
    c. they show the exposed wires and the movement of the wire/pulling on the socket probably is not good for socket-wire connection longevity,
    d. there is not a heat shield to protect the socket and wiring from lamp heat.
    Because of these factors many contractors do not like the spring/floating socket and prefer the more finished, robust look/feel and ease of relamping of fixed sockets.

    3. At Volt we think this is a very important issue and one we spent a great deal of time planning for. We felt contractors prefer fixed sockets, plus we felt they were more robust and solid, however we did not want to inhibit wide beam spreads. Accordingly we put all our fixed sockets on brass risers so that when the lamp is inserted the face sits between 1/4"- 1/2" below the fixture opening/lens to insure complete 60 degree beam spreads. Just enough space to still fit a lens or retro LED.

    4. We experimented with a new design which we have in two of our spotlights which uses a spring loaded socket but has a heat shield to prevent the socket from falling back inside the spring (I believe Cast does this as well) except we also added stoppers so that the whole mechanism doesn't pop out of the fixture like a Jack-in-the-box. In essence its a spring loaded socket that looks like a fixed socket (heat shield/hides wires/doesn't pop out of the fixture.

    5. On some fixtures we made physical design changes to insure proper beam spreads. Take the Top Dog for example. It was based on the concept of the Big Smoky (we liked the concept of 360 glare control, adjustable glare guard, and machine threaded body, however the fixture was limited in its results because it significantly blocked the ability for wide beam spreads). Accordingly we shortened the body and the glare guard until we achieved full 60 degree spread by having the lamp face 1/4" from the mouth of the fixture. The downside is we had to make another version with 1/2" space from lens top accomadate LED's which are slightly longer than halogen MR16's. (We are coming out with a Top Dog Second generation with fins for LEDs and wide mouth).

    6. Billys comment about test them yourselves is also spot on. Most of the fixtures we've tested have a big difference between 60 degree beam spreads with fixture front on verses just bare lamp (i.e they block proper wide /full illumination). That is the benefit and what I like about Coppermoons spot-- it has a nice wide mouth and enables wide beam spreads.


  6. Pro-Scapes

    Pro-Scapes LawnSite Platinum Member
    Messages: 4,180

    I appreciate the posative comments on my post. It should also be noted the coppermoon has a silk screening on the lens. This can inhibit the full 60 degrees but it still works well with these lamps. The silk screening does alot to soften the edges of the beam. If you are using this fixture (cm125) you should see it with and without the shroud on it. The silk screening surprisingly works nice.

    I have PILES of lights I have tested over the past few years. Some are definatly more suited to the narrower beam spreads while others (like Alan said a wide mouthed but I definatly like the fixed socket like the Gambino bullets I use) work rather well with a full assortment of beam spreads. I just did some nice large wax myrtles around a pool with a series of 35w 60 degrees in the Gambino bullets and dusted the tops lightly with some mounted at a distance behind some Sago palms with a BAB lamps pilling light on to a taller maple and pin oak behind them. Another one with a 35w 24 degree tagging some taller trees in the background. While all of the lamps performed as speced I did need to remove the hex louver with the 60deg lamps to get the full photometrics. It wasnt a problem in this situation but again one needs to be fully familiar with the fixtures you choose. Seems like there is endless considerations that we as lighting designers need to make. I try to learn something on every job and thats why I stand by my practice of viewing each job with my clients before I bury the wires.
  7. emby

    emby LawnSite Senior Member
    from Ontario
    Messages: 380

    Billy thats some great sharing of your experience there. I too have had fun trying different products and I like the fixed socket as well.
    I have tried others that are not fixed and when placing the shroud onto the fixture the lamp is somewhat off center which completly changes the beam spread of the lamp. I often use a laser pointer during the day to locate my center beam and it is really frustrating getting back up into a tree opening a fixture up because the lamp is not sitting on center because of the floating socket.
    One question for you Billy and that is how have you been attaching any louvers or spread lenses onto the lamp using the CM-125? I have been using a little dab of silicone how about you?

  8. Pro-Scapes

    Pro-Scapes LawnSite Platinum Member
    Messages: 4,180

    There is a clip they make for this that holds the lens to the lamp face. They get expensive but really make for a clean job. I have a few hundred of them here as they come with the Gambino bullets if you may need any. I think Coppermoon also has them as well

  9. INTEGRA Bespoke Lighting

    INTEGRA Bespoke Lighting LawnSite Platinum Member
    Messages: 4,102

    Ken, the MR16 lens media clips that Billy shows are readily available. Most manufacturers offer them as an accessory and you can easily get them from Turf Care along with reasonably priced glare louvers, optical spread, linear spread, frost and coloured lenses.
  10. Pro-Scapes

    Pro-Scapes LawnSite Platinum Member
    Messages: 4,180

    Not all clips are created equal so be careful. Some are just cheaply powder coated and flake off after a few months then rust. Some are stainless...I saw some that the ring itself was much to wide cutting into the beam spread and yet others are significantly wider than the lamp itself becoming an issue in some fixtures. I recall one I could not clip into a Unique Lunar (could not just let lens sit in nose due to angle)

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