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View Full Version : the best 20 watt 60 degree mr-16


David Gretzmier
07-13-2009, 08:10 PM
Since I don't like pars, I use the 20 watt mr-16 60 degree bulb pretty extensively, and my current distributor has been out of that bulb for 3 months. I've tried a few others, not super happy with them, but I am wondering what you guys are using that gives a good even spread, preferably a glass cover as well, minimum 3000 hour life. some 60 degrees Ive tried seem the same as a 36-40 degree BAB.

Lite4
07-13-2009, 10:00 PM
David,
For an MR16 the very best is the GE constant color. The GE-BAB/CG (Clear glass) front is the best on the market in my opinion. They are only a couple bucks more than the Ushios and you can buy them online too if you like.

Pro-Scapes
07-14-2009, 06:48 AM
I have my first couple jobs out there exclusivly in GE and so far so good.

The sylvania tru aims did ok for me but nothing to write home about.

I use mainly ushio and use alot of 60 degree lamps too but my main lamp would be a bab. If I need that wide floody light of a par I usually use 35w 60 with a lens or a wash fixture

The ushio eurostars seem to work at an acceptable level as long as you remain in the mid 11's Give coppermoon a shout on them. They have them in stock.. I order them in boxes of 50 at a time and get a real fair price on them. Doug always seems to have in stock what I need.

JoeyD
07-14-2009, 11:02 AM
can you use a spread lens and a bab?

INTEGRA Bespoke Lighting
07-15-2009, 09:26 AM
I stopped using Ushio 2060 MR16s a few years ago due to longevity issues. Instead you can pop an optical spread lens in front of a GE BAB and get pretty much identical beam spread to a 60 Deg. Lamp.

I have also seen frost lenses in front of BABs that come pretty close to the same effect.

Eden Lights
07-20-2009, 11:56 PM
I stopped using Ushio 2060 MR16s a few years ago due to longevity issues. Instead you can pop an optical spread lens in front of a GE BAB and get pretty much identical beam spread to a 60 Deg. Lamp.

I have also seen frost lenses in front of BABs that come pretty close to the same effect.

X2, Ditto, Amen

steveparrott
07-21-2009, 08:11 AM
Interesting side note on 60 degree MR-16's. You'll notice on MR-16's with smaller beam spreads that the inner quartz capsule (houses the filament) is clear. The 60 degree capsule is frosted.

To explain why... in a reflective light source such as the MR-16, different beam spreads can only be achieved by changing the shape of the reflective mirror. Since an MR-16 has a fixed size, the shape of the mirror is changed by setting small angled planes in the mirror's surface. The angles of these planes mimic the shape of a larger bowl.

The little planes can only be angled to achieve up to a 36 degree spread. To achieve a 60 degree spread a different tactic is used. Up to the 36 degree spread, the bare filament acts as a distinct focal point, so that its light reflects off the bowl in a pure parabolic fashion - in other words, a single beam of light hits the bowl to reflect in the desired direction.

To get a greater spread (60 degrees) the manufacturer frosts the quartz capsule. Now you don't have a single point of light in the parabolic focal point, you have light emitted from the entire length of the quartz capsule. This causes beams of light to hit the angled planes from different directions, and the reflected light is also spread in many more directions.

The resultant beam is distinctly different from the 36 degree (and lower) MR-16's. There is less of a hot spot and the edges are much more diffuse (less sharp).

There may also be differences in lamp life since the frosted quartz retains more heat than the clear capsule.

Terradek
07-21-2009, 09:15 AM
Steve,
Thanks for the explanation...it was information that I had not heard before...old dogs can still learn. best, gerry.

David Gretzmier
07-21-2009, 11:58 AM
hmm. I have some 60 degree 20, 35, and 50 watters that are not frosted. does that mean they are not 60's but 36's?

Lite4
07-21-2009, 06:14 PM
Interesting info Steve, Thanks.

INTEGRA Bespoke Lighting
07-21-2009, 06:27 PM
Interesting but how does this explain the 60 Degree lamps that Ushio produces? These do not use a frosted lamp capsule, they are clear like all others and the beam spread is developed by the reflector just like as in all other MR16 lamps.

JoeyD
07-21-2009, 06:47 PM
I just looked at some Ushio 60degree and they are clear as is the Osram I have here?

Pro-Scapes
07-21-2009, 10:17 PM
If I am seeing these lamps I am looking at clearly it is obvious there is a diff between a BAB and the 20w60deg. More facets at different angles playing off eachother to increase the projection angle ? Sort of like fun house mirrors ?

Anyone else compare them side by side ? Curious to see how you would describe it.

steveparrott
07-22-2009, 01:22 PM
I stand corrected - some mfgs don't go with the frosted capsule.