How to set max intensity for channel?

I would like to know, if is possible to set max intensity for certain channel to let's say to 80% so the light would have 80% brightness when it is set to full intensity. I'm asking, because recently we get (at regional theater where I work) a new brighter projector. We use it in lot of shows and control it via EOS ETC. In each show we have plenty of cues (usually 50-120) and I'm kind of lazy to change intensity for all of the cues manually, so I'm trying to find easier way to do it.

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