[BCMA] FW: Question about LED bulbs

[Moderated BCMA subscriber listserv.]

I have seen Par 38's used with both good and bad results.
CRI of 95 is very good.
1. Where things go wrong is the beam spread.  I have not checked the beam spread for the Sylvania lamps they chose but in general most of the LED par lamps have a fairly wide spread which in some cases (depending on how the gallery is set-up, distance throws, etc.) results is a "general wash" of light which does not emphasize the object being light.  No shadows (at least not in the right places) so there is no 3 dimensional look. 
2. Dimming:  LED Lamps can be problematic if dimming is used.  This can be solved but bear in mind there may need to be some adjustments or changes in the dimmers.  Also mixing different LED's on a circuit can result in things like flickering and control of dimming. (again different dimmers may help in this respect) 2. Colour Temperature: 2700K to 3000K ???
3. Single ver. Multiple LED light source:  If the LED lamp used multiple LEDs to get the power you also have multiple shadows since the light originates from different angles. (This can also be distracting)

I would recommend some testing before doing an all-out change in a gallery. If the reason for change is for cost savings & lower maintenance this is great, but in the end you still want the gallery to look every bit as good if not better for the money spent.

I have used GE, Saylvania and a few other lamps but I like the Lumicrest LED Lamps (Par 20 and Par 30. Unfortunately they don't have Par 38 lamps.) which have some advantages.
The lamps have Single point LED sources, CRI 93+ and they have interchangeable lens for beam spread and come in both 2700k or 3000k colour temp.

The Par 30 lamps are 13 watts (850 lumens) Company Information:
Lumicrest  50 Garden Ave 
416 479 0132	Suite 101
http://www.lumicrest.com
Toronto ON  M6R 1H6  CA

Hope this helps,


Norm Charbonneau
Royal BC Museum