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cnbales
11-14-2012, 09:40 AM
My LED lights don't turn on until approximately 16% power is applied to them. Likewise, the brightness stops around 88%. Do I make changes for this under ->Defaults ->Minimum / Maximum Output Level or do I do it under ->Library ->Dimming Curves?

If it is in dimming curves then I need help (I have watched the video). The first highlighted block starts at 0, 0 at the bottom left hand corner and the last one ends at 255, 255 in the top right hand corner. What would the settings be in Dimming Curve Design to achieve 16% to 88% output levels? (If this is the way to do it)

What is the relationship that the dimming curve and the Minimum / Maximum Output Level have. Let's say, that I set the Maximum output level at 88% and I have established different dimming curves are the dimming curves affected by the Maximum output level?

Thanks Guys...getting excited. My oldest two children and I completed the spiral mega tree, snowflake fall, and Bethlehem star and we still have a ton of work to do.

JHinkle
11-14-2012, 10:50 AM
Those two topics are completely different.

Min and Max setting say clip output levels (0 to 255) so they never go below or above the stated values.

If you have Max at 220 --- then all output values from 221 to 225 are going to be clipped to 220.

Likewise if the Min value was set at 50 - then all output values from 0 to 49 are going to be clipped to 50.

Dimming curves allow you to remap output values - but you must deal with absolute values not percentages.

A one-to-one mapping is a linear line (straight) from 0 to 255.

Dimming curves are usually used to remap output values so the lighting intensity from one color of LED matches the intensity of another color since the observable intensity is different for Red, Green, and Blue LEDS when driven at the same PWM level.

Your using percent power - so let me guess and state that your lights come on at 255 * .16 = 41 and no longer brighten at 255 * .8 = 204.

Dimming Curve - Hor axis is what is sent to controller - Vert Axis is what is used by the Sequencer to give to linear response from 0 to 255 (0% to 100%).

So you say that all output values less than 40 produce Black - and all output values greater than 204 produce no additional intensity change.

So --- in the Dimming curve --- move the First cell UP the Hor axis to 40 and the Last cell DOWN the Hor axis to 204. Then remap all the cells in between to form a straight line.

NOW - when the sequencer wants 0% (0) --- 40 is sent to the controller. When the sequencer wants 100% (255) - 204 is sent to the controller and every value in between is now linear to those end points.

Please be advised that reality is NOT linear.

To get a true linear intensity output - the actual curve is not straight (simplistic view) but curved.

Hope that helps.

Joe

BrianJ
11-15-2012, 08:54 AM
Those two topics are completely different.

Min and Max setting say clip output levels (0 to 255) so they never go below or above the stated values.

If you have Max at 220 --- then all output values from 221 to 225 are going to be clipped to 220.

Likewise if the Min value was set at 50 - then all output values from 0 to 49 are going to be clipped to 50.

Dimming curves allow you to remap output values - but you must deal with absolute values not percentages.

A one-to-one mapping is a linear line (straight) from 0 to 255.

Dimming curves are usually used to remap output values so the lighting intensity from one color of LED matches the intensity of another color since the observable intensity is different for Red, Green, and Blue LEDS when driven at the same PWM level.

Your using percent power - so let me guess and state that your lights come on at 255 * .16 = 41 and no longer brighten at 255 * .8 = 204.

Dimming Curve - Hor axis is what is sent to controller - Vert Axis is what is used by the Sequencer to give to linear response from 0 to 255 (0% to 100%).

So you say that all output values less than 40 produce Black - and all output values greater than 204 produce no additional intensity change.

So --- in the Dimming curve --- move the First cell UP the Hor axis to 40 and the Last cell DOWN the Hor axis to 204. Then remap all the cells in between to form a straight line.

NOW - when the sequencer wants 0% (0) --- 40 is sent to the controller. When the sequencer wants 100% (255) - 204 is sent to the controller and every value in between is now linear to those end points.

Please be advised that reality is NOT linear.

To get a true linear intensity output - the actual curve is not straight (simplistic view) but curved.

Hope that helps.

Joe

is there a easy way to do the remapping or is it a cell by cell process?

JHinkle
11-15-2012, 09:23 AM
Sorry - no easy way.

Cell by Cell.

Nice thing is that dimming curves can be used multiple times - so once you go through the process - it's done.

Joe

cnbales
11-15-2012, 12:06 PM
Joe,

That was extremely helpful information regarding the dimming curve. I will make adjustments there.

My new question is why have the Max / Min output? I know that the dimming curve is to adjust according to different brands and colors of lights, so now I'm not understanding why the Max / Min is even an option.

JHinkle
11-15-2012, 10:18 PM
Answer - I don't have the foggiest idea.

When I disected the Vixen file so I could provide a conversion - Vixen had them in its file.

So to not break a Vixen converted sequence - I included it - was simple but does eat clock cycles.

If no one with a Vixen background can tell me why someone would use them - I will remove the code as it will increase performance since those comparisons are performed on every time slice - every channel.

Joe Hinkle

jrock64
11-15-2012, 11:55 PM
The original intent was to take a show down to 80% max output to save amps on output.

Couldn't the same be done with a master lighting channel.

JOel

JHinkle
11-16-2012, 07:44 AM
The original intent was to take a show down to 80% max output to save amps on output.

Couldn't the same be done with a master lighting channel.

JOelYou got it.

Make sense when you understand the reason behind thinks.

Looks like I'll remove it soon.

Speaking of master lighting channels - remember - you can take a Sub-Master Lighting channel and make multiple channels shimmer.

Joe

kychristmas
11-16-2012, 09:16 AM
You got it.

Make sense when you understand the reason behind thinks.

Looks like I'll remove it soon.

Speaking of master lighting channels - remember - you can take a Sub-Master Lighting channel and make multiple channels shimmer.

Joe

If it doesn't get in the way, why remove it? I don't use it currently, but I have used it in the past.

Edit: Nevermind, I read the part of "eating clock cycles" as "IT Does Not." Given that it does eat processor, I understand removing it.

cnbales
11-16-2012, 08:40 PM
Joe,

Is there a video on how to use the Sub Master Lighting Channel to make multiple channels shimmer? If not is there anyone willing to make one?

injury
11-16-2012, 10:36 PM
Joe posted a quick howto in this post http://doityourselfchristmas.com/forums/showthread.php?22713-HLS-Use-a-Sub-Master-Lighting-Channel-for-Shimmer haven't tried it myself

cnbales
11-17-2012, 12:19 AM
Thanks for the reply injury.