I can’t say how sigil opening compares to evocation, as I have never done one before. However, I have had some results with sigil opening when it is superimposed on an image you identify as the spirit itself. With my experience, the picture has began to come alive, and will even change it’s appearance so that the picture is halfway the original and halfway distorted, and will begin to move, jumping out of the picture like a sigil jumps of the page. It works primarily like this for the sigil opening, but the residual effects come in dealing with the spirit astrally.
I have been doing this with Ladilok, who I had put the intent of learning from in lucid dreams. I originally created an image just to run with a Radionics computer program called CyberShaman, set to run while I was asleep. However, I found myself concentrating on it one day, and BAM!! The area around me starting vibrating, and as I zeroed in more on it, my head and body began to rumble, cranial pressure began to build, and the original female image began to change. She began slightly moving, then she blinked, her skin color changed, and then she began to walk. I got heat and definitive hand-like pressure resting on my shoulders, and set the machine to run once than happened. A similar activity happened with Bathin, who I ran the same procedure with.
I had my longest running lucid dream to date, and with a woman wearing red being hallmarked through most of it. I haven’t trained any skill in lucid dreaming, so I didn’t get too much from it yet. She was very informative and extremely intelligent, and she brought along two other women. Again, I forgot the whole damn thing, but I do know that I had no dream trigger, and just said, “hey, I’m dreaming.” Nothing guided me to that realization, I just realized I was dreaming out of the blue.
I wouldn’t say this is full-blown evocation, but it certainly contained elements, and produced an obvious result. Any fault with the result was mine really, as I didn’t do a damn thing to continue my focus, nor did I write the dream down at all. It was crystal clear and easy to orient with, too. This type of activity has also acted as a huge momentum starter, as I am a beginner, and with this success and interaction, I am wanting to go further, as it appears that this power was far more accessible than I previously thought. And here I am, priding myself on confiding in spiritual forces, and yet I doubted they would be this close.