0% opacity don’t work

In my score I’m hidding some items, like noteheads or tuplet numbers, by 0% opacity. It works in write and engrave mode, but it don’t work in print mode and when I print the score or make pdf, this items are visible.
Could anyone help mi with it? Why it don’t work? Thank you.

Try printing in color, not monochrome.

Thank you very much, it works.

Wow - just ran into the same problem and that’s definitely the solution! So: why DOES this work? Shouldn’t 0% opacity even if printing in black and white result in an object “disappearing” also? This seems unintuitive…(just curious!)

  • D.D.

This was among the most popular questions when Dorico was only some weeks old… I suppose monochrome printing bypasses the colour property. Anyway, google search engine should have helped here :sweat_smile:

I can see why he might not have searched - it just feels (at least to me) like a bug since it doesn’t seem intuitive that setting a pdf to print in color would be the solution…But you’re certainly correct it’s out there for sure.
Best -

  • D.D.

Monochrome = 1-bit, i.e. everything is either black or white. Transparency is handled by the A (alpha) bit of the ARGB 32-bit colour space, and when you convert an ARGB colour with A set to 255, that converts to 1-bit as black rather than white.

I guess the transformation from color to monochrome doesn’t handle the special case of an “invisible object with opacity zero” by ignoring it completely. It is obviously “wrong” to convert it either to black, or to opaque white.

But if you did handle that special case, somebody would probably complain about objects with opacity 1% not being handled “correctly” (for some common sense but non mathematical definition of “correctly”)

I have to admit, I did not even know that Monochrome meant only black or white.
I always thought it was “no colors, but multiple steps of black”, but that’s pure lack of knowledge on my part :wink:

So, I guess there already is a process that decides if an item that is set to color blue and opacity 35% is then to be printed in black or not printed at all? And should this process not come to the result that an object of whatever color should be not printed at all if its opacity is set to 0%?