Using a OSC camera with just a Ha filter will only give you 1 channel to create a uni colour image and usually it’s only orange , salmon and a reddish brown palette
Your best using a dedicated OSC Dualband filter <7nm or even a Triband filter to extract the Oiii and Sii channels to create a narrowband false palette eg SHO or HOO and others
I have noticed your images are predominantly orange.
I think you use Siril and I’m sure Siril can separate channels from a multiband filter to create a Narrowband composite
If not, try another post processing software , I use Startools and have processed many Narrowband bi colour OSC images . Lately using my new Mono set up , Startools provides the whole spectrum of Hubble palette colours on emission nebula
Pixinsight is probably the best at creating Hubble palette renditions but requires time and applied learning.
Dualband or Triband filters are specifically designed for OSC cameras to create Narrowband images. First recommendation would be L Ultimate, then Antlia ALPT
Another option is to buy an Oiii and Sii filter and capture data from these filters to add your Ha data which will allow you to compose all three channels and create SHO , HOO , OHS and other palettes. Of course a OSC with Mono filters won’t produce the same results as Mono
Hope others can chime in to provide further advice
