My experience of solar imaging is limited. For the recent partial eclipse I bought a Baader Solar Filter for the GT81:
Then I attached my DSLR in the normal way using a T-ring, and put the whole assembly onto the Porta II, having first removed the red-dot finder:
To complete the picture I used the Canon’s LiveView function to view the solar disc on a laptop. I can’t bring myself to view it directly through the scope. Call be a Luddite if you will..