How to make the Microh LED par not flicker when dimming, or a better LED PAR?

[FLOYDIE]

This is the first time I and the theatre I am designing in are using Microh LED Par TRI's. The website says they are flicker free, but they do flicker, when fading out. Is there a profile or personality or something I can do with the ION to make the dimming out more smoothe at the bottom.

Also, have an option to buy another set of LED pars if there is a better one out there, that would be under $450 canadian. Preferably one that has a nicer white, could have the incandesent curve option, and doesn't flicker out on an 8 second fade.

We start hang in a week, so would love some replies soon.
Thanks
Floydie

 

[David Ashton]

not a hope, sorry, this article explains why,
Jands - What To Look For When Judging An LED Fixture’s Colour Mixing Capabilities…

 

[dj41354]

"Flickering" when fading out is common on lower end LED fixtures, and is a direct result of their cost/performance design tradeoff. "Steppy" is a somewhat more descriptive term for this, as the problem really is a function of limited resolution.. meaning there's not enough "steps" of intensity to smoothly fade through 0% to 100%, and those first few steps from "off" are noticeably large. It's the combination of high resolution (lots of intensity steps) and high PWM rate that make smooth fades (down to zero), and result in flicker free operation.

The "flicker free" spec. you see on data sheetsheets has to do with the LED PWM rate, and is basically saying that the PWM rate is high enough that you won't see any flickering if you take video of the fixture. I'm not sure there's complete agreement on the minimum PWM rate that's flicker free, but I've read 300Hz is sort of a lower limit, and 1KHz and higher is the gold standard. It's hard to find information information about PWM rates, but here's an article that goes into it a little (look for the "Dimming" section about half way down): http://www.mikewoodconsulting.com/articles/Chauvet_Colorado_Batten_72.pdf

The combination of high resolution and high PWM rates is what you find on high end LED fixtures, highlighting the significance of that all important cost/performance tradeoff.