Hi James,
I’ll try and answer your questions:
1. Yes a Ha telescope will only let light through centered on around 656nm with a bandwidth of < 10 nm (1 Angstrom). 2. Yes whiter areas are emitting more Ha and the darker areas less. So solar flares appear bright when they occur and filaments appear dark. Your image is very nice, showing plenty of detail in AR 3590 from last month. 3. Not sure what the blue filter is for but is likely to be a UV/IR blocking filter so care is required not to damage it (the visual colour of a filter does not necessary indicate what wavelengths it transmits or blocks).