Hi cancain123, as Marty notes, there is a reason why it takes a much more sophisticated and expensive filtering system to observe the chromosphere directly.
In my presentations on solar filters, I use these graphic representations to demonstrate why you can not use a white light solar filter with a nighttime H alpha filter of any bandpass to see features of the chromosphere such as prominences, filaments, flares, etc.
The H alpha absorption line is only ~ 0.12 nm (1.2 Angstroms) wide.
In pane 1 below, a bright white painted exterior wall represents the intensely bright photosphere, and the window represents the broad dark H alpha absorption line in the continuous spectrum of the photosphere. This can be thought of as looking into a dark room with no other windows, in which a candle glows. This candle represents the H alpha emission line from the chromosphere, ~ 100,000 times dimmer than the photosphere.
In pane 2 we use a standard white light filter to dim the photosphere to a safe level for observation. This has required a 100,000 times reduction in brightness, but we have also dimmed the brightness of the emission line (the candle) from the chromosphere 100,000 times as well.
Adding a nighttime H alpha filter (pane 3) reduces the brightness of the photosphere a bit by eliminating all but the red wavelenghts around the H alpha absorption line, but cannot do anything to bring back and reveal the H alpha emission (the candle), which has been greatly reduced in brightness by the white light filter.
The only way to see the H alpha emission (the candle) from the chromosphere is to completely eliminate light coming from the photosphere (the wall), while leaving the window un-dimmed. We can then peer into the window (the absorption line), where the chromosphere - the candle - can now be seen in pane 4.
So you must completely block all wavelengths from the UV (200 nm) to the far IR (3000 +nm) to OD5 (1/10,000), while simultaneously passing an extremely narrow slice of the spectrum (0.1 nm or less) essentially unimpeded. You cannot do this easily, or with any filter designed for observing the photosphere. It takes multiple filters, and an Fabry Perot etalon filter with very high manufacturing tolerances, to be able to do this.
Hope this helps to understand why you can't really implement your idea with any real hope of success.