Opacity Mask Options?

[Cactus Cowboy]

I'm still using Windows version of Adobe Illustrator CS6. My question has to do with the Transparency & Gradient Palettes. Now I do understand how and when to use an opacity mask that's seems simple enough. My long running confusion comes from the three options related to the mask. When would one use these options, how & why? The last book I have that I read attempts to explain it (w/graphics) is "How to do everything with Illustrator CS" by Osborne but I must be dense because I still don't quite get it. Can some of you power users help me out by pointing me to some examples, video or a simpletons explanation preferably all three. Thanks in advance.

    

[Doug A Roberts]

they apply to groups and masks, rather than just opacity masks specifically.

Isolate blending means if you've applied a blending mode, such as multiply, to a group, it will only affect objects in that group, not objects underneath.

Knockout group means any transparent objects in a group are only transparent to other objects, not those in the group.

Opacity & Mask Define Knockout shape means the amount that shows through an object in a knockout group is proportional to its opacity setting. Unless this is checked, nothing shows through.

How to edit artwork using transparency and blending modes in Illustrator

[Cactus Cowboy]

Thank you Doug for those definitions.

[Monika Gause · Accepted solution]

You want to read a text by Mordy Golding about this:

https://creativepro.com/illustrator-how-to-technique-a-real-knockout/

Don't worry too much about the "Opacity & Mask ..." - at least for the moment. Knockout groups will keep you busy for the next few years anyway.

If you prefer video, there is a course at Lynda.com that concentrate on transparency (paid ressource)

Illustrator: Seeing Through Transparency

[Doug A Roberts]

yeah i use knockout group all the time, but don't think i've ever touched the other two options except to figure out what they did.

[Cactus Cowboy]

Thank you Monika, your links helped me immensely especially the one on stitching. Right on target.