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Old 27-06-2009, 04:28 PM
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Tandum (Robin)
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Join Date: Apr 2008
Location: Wynnum West, Brisbane.
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Quote:
Originally Posted by peter_4059 View Post
Wow - you are hitting them with a fair current at 12V with a 120 ohm resistor - I calculate you needed 270 ohm. Are they lasting ok?
Yes they are fine. You'd need the data sheet that comes with the LEDs to get the current needed for optimal performance. Once you have the current you can calculate the resistor. 2000cmd is bretty bright for an LED, I only used 4 of them. The data sheet also gave me the FOV of the LEDs, which was very narrow, so I didn't use internal baffles etc, I just pointed them to the back of the box. I adjust exposure time to get the recommended 30% well depth for a flat.

http://www.hebeiltd.com.cn/?p=zz.led...tor.calculator
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Last edited by Tandum; 28-06-2009 at 01:38 AM.
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