Colour shape on LEDs - incorrect colours

[nigelj]

I have a couple of LED battens and 4 old Eurolite LED pars in my dining room, whilst I'm getting to grips with Titan.

I've tried to program colour shape...most work fine, but if I choose the Red+Blue or Blue+Green shapes the output from the fixtures is very wrong...I get various very pale shades, followed by one of the colours that should be there (e.g. when I've selected the Red+Blue shape the red is OK), then it goes back to the very pale colours.

I've spoken to a colleague who says it's a common issue and the resolution is to build my own colour chases instead.

Has anyone found out what the issue is causing this?

Nige

[icke_siegen]

The reason is the way how shapes essentially work: they apply a modulator to the values which are set otherwise. The modulator itself can yield from -100% to +100% (i.e. from the negative to the positive maximum value of the very attribute).

To get a basic understanding, I'd recommend to start with only a single-color shape, e.g. a red one. If you apply this to fixtures with the color set to black (RGB = 0,0,0), then you will see only the positive part of the slope (e.g. a sine wave). Result: the fixture changes between black and red. If you apply this to a fixture set to white (RGB = 255,255,255), then you will see only the negative part of the slope. Result: the fixture changes between white and cyan (where the red value in the shape is negative). And if you apply this to fixtures with the origin color set to med grey (RGB = 127,127,127), then they will change between red-ish and cyan-ish - and that's most likely what you are observing. With the red+blue shape, the maximae are magenta (when coming from black), and green (when coming from white).

That's not exactly ideal, but it's the current way to work. When you understand these mechanics, then you can achieve some nice results. Else, color chasers (in particular with the new setting 'release between steps') and pixelmap effects are other good tools to help you .

However, Avolites has been working on another approach for the shape engine for quite a time now, and let's hope we'll see some results soon.