Many dark nebula are visible in this view, located close to the bright star Sadr (Gamma Cygni). The most prominent dark structure is called LDN881 and it looks a bit like a black soap bubble with curly edges. I could not find a specific name for the bright nebulous structures on top. SII emissions are usually pretty weak, but I was really surprised by the amount of SII signal in this area.
The color image was composed of only 2 channels: data from my SII filter was used for the red channel and H-alpha was used for the blue channel. The green channel is a multiplicative combination of both SII and H-alpha data. The resulting palette looks similar to a classic three-filter Hubble image, without having used any OIII data.
At my location of 52 degrees North, there is almost no
real astronomical darkness during this period of the year and the atmosphere will remain partially illuminated by sunlight. In the astronomy community these are known as ‘grey nights’, referring to the lack of real darkness. Views through the telescope will appear more washed out. There are still lots of possibilities to image during grey nights when using narrow band filters, especially with very narrow 3 nm filters as they block most of the unwanted sunlight.
I always find it very helpful when other photographers post their individual channels, so feel free to compare the starting stretched images (greyscale) with my final result.
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