I currently have a Baader AstroSolar filter for my Sky-Watcher Skymax 127 Go-To scope and I want to step up my solar observing. Can I fit an H-alpha filter and what would I be able to see with it?
The AstroSolar filter that you are using will give excellent white light views of the Sun, showing sunspots and granulation. However, installing a Hydrogen-alpha (Ha) astro imaging filter will not allow you to see detail on the Sun such as loops and prominences. Instead, solar astronomy requires a piece of equipment called an ‘etalon’, which focuses in on an extremely narrow band of wavelengths; confusingly, these are often referred to as H-alpha filters as well.
Etalons are found in solar telescopes like those made by Coronado, Daystar or Lunt, and also come as separate units that can be fitted to the front of refractor telescopes to be used with an energy rejection filter (ERF) and a blocking filter, which require specialist engineering techniques to install. Unfortunately, your scope design, a Maksutov-Cassegrain, is unsuitable for these options; to observe or image solar loops and prominences, you would need to buy a solar scope or a refractor. Daystar also makes an H-alpha etalon eyepiece called a Quark and, provided you use a suitable ERF installed on the front, you could use one with your Maksutov-Cassegrain.