In the Panoramic Capture itself, there are restrictions on the post-process. I send example solution:
You need change Material Base Color in PanoramicCapture Content/Materials
Change code (look image)
This way you can adjust the brightness (exposure) of your picture. But the bloom effect is hardly possible, as there are limitations.
Also, do not make the image too bright, otherwise there will be a problem in the image.
In general, this approach can help you use even custom shaders for your image.