A version with annotations, the spectral profile and the raw image can be found in the revisions.

2.5° north of Albireo (a beautiful binary star or visual double, that resolves into a cyan blue and a brighter orange companion) is a small planetary nebula known as Campbell's Hydrogen Star. The central star belongs to the class of WC-stars, a rare class resembling their massive counterparts, the Wolf-Rayet stars. WC- and Wolf-Rayet stars can be distinguished spectroscopically. The WC-star is a low-mass sun-like star at the end of its life that has ejected most of its mass und still loses mass in form of hot winds leaving the stellar core. These winds let them resemble Wolf-Rayet stars, however their composition differs. Wolf-Rayet stars are characterized by strong emission lines of helium, nitrogen, carbon, silicon and oxygen while the hydrogen lines are absent or weak. The spectrum of Campbell’s Star displays prominent hydrogen emission lines, as well es carbon and maybe helium lines as well as others I was unable to identify yet.

As a reference I also marked a type A star (or something very similar) with clearly visible hydrogen Balmer-lines (white arrow).

To my surprise I noticed two, maybe three strange objects (boxed in white). The two leftmost objects are marked with white lines. Two additional markers identify the distance where the H-epsilon line should appear (blue light) and another marking the IR-region. The third object in the upper right maybe identified by its “ghost” on the left only displaying the IR-light. Maybe pitch-black asteroids with little reflection of visible light? I have no idea what they are, but they are not stars and I have not observed something like that in other pictures that night, so I think they are no artefacts. If anyone has an idea, please let me know :-) I'll try to find out if there have been known asteroids.

edit: I learned that these infrared sources are infact stars, dim in the visible part of the spectrum but strong in the IR. Thanks you Johny! I'll do some research on them in the future!