White-to-black gradients in opacity masks don’t go fully transparent
For opacity masks, 100% White should represent a 100% absence of masking and 100% Black should represent 100% masking (like in Photoshop).
The current system in Illustrator seems very unintuitive and flawed – a basic white to black gradient does not even totally obscure an image/object at one end of the gradient.
It shouldn't be the case that you then have further reduce the opacity of the gradient colours to achieve a standard gradient effect.
Make sure you use RGB black instead of Grayscale black in your gradients when making opacity mask in a RGB-based document to avoid shallow blacks and not fading to a complete zero.
More on that in the comments.
If you happen to have the same problem, please still add a vote to the request, to track statistics.
I know exactly what are you talking about.
You are in RGB color mode, right? And then you apply the standard 'White' Black' gradient from default swatches? and where it’s black on the end, the object you mask does not go completely transparent?
Well, it’s because for an unknown reason the team included a wrong gradient in Web profile. It goes not to black that is RGB 0,0,0, but into K100 — which is grayscale black, which is (for the same kind of reason) is lighter then the absence of light that is RGB black, because it's a 100 of black paint. A black from a different color mode basically.
If you select this black gradient stop, open Color panel and change Grayscale to RGB via panel menu, it fixes, and now the mask fades into zero opacity.
But other than this bug (and I am moving this into Bugs branch) — Ai’s Transparency model is the same as Photoshop, and even more powerful, because you can put any complex layered artwork in a mask. It comes with an absence of drag'n'drop method, like in other apps, but that’s a different story and a different request: https://illustrator.uservoice.com/forums/333657/suggestions/32265136
Should have included an example, apologies
See this screenshot
Where's the black/solid gradient stop located on the vector object, in relation to the image being masked? It looks like it could be located to the right of the image's edge, which would certainly not completely obscure the image as you expect.
The live gradient annotator thing is a massive help in this case, because the panel's preview doesn't tell you where the stops are in relation to the vector object being used as a mask.
I'll agree that opacity masks can be a little unintuitive, I've had issues with them in the past when a mix of color spaces was involved.
Please, tell more about your Preview mode, document color mode and 'Appearance of Black' preferences.
Also try to juggle them and see if anything changes.
I use Illustrator CC 21.1.0 on Mac OS X El Capitan ver 10.11.6
I encounter a problem with transparency opacity mask. Basically it doesn't cover properly the area where it should be fully transparent (black part). Despite the colour being set to 100% black ant opacity 100% there still is a hint/shadow of colour. In this case I would expect that from the bottom gradient goes up gradually form completely transparent to 100% opaque. And this going on for some time. See attached screen shot.