ive been having a problem scrying lately it seems when i use the black mirror i see the white glow and sparkles of light but then instead of a vision i see rings of purple/violet light almost gaseous coming from me and going into the mirror and my third eye starts to ache like crazy does anyone know how to change this? i mean ive seen visions and spirits before years ago but now everytime i try its the same thing over and over regardless of lighting in the room. does anyone have any ideas that could help?
Maybe you just need to continue in your effort for some time and see if it doesn´t break trhough 
Let your consciousness go within, let it drift into the inner world. Let go, almost like when you fall asleep. It’s a subtle process, don’t force it, let it happen.
What works for me is having the mirror at a slight angle. Then focus past the mirror or look through it. Another technique is sit in a dimly light room facing the corner. Now without moving your head stare up in the corner by the ceiling by only moving your eyes up into your head.
Just don’t get caught up in over thinking about not seeing what you expect to see.
Hope that helps.
Is it correct to say that one of the keys to success in scrying spirits is not only maintaining an unwavering gaze but also a fixed visualisation of what you are calling? I have no problem getting into the theta-gamma sync and engaging the necessary physiological shifts but it’s harnessing and utilising my visualisation/living magickal imagination after years of neglect that seems to be holding me back from entering into full conscious contact.
Practice scrying every day seems to be the universal advice here.