MW in Ophiuchus: a 9-panel mosaic

9-panel mosaic stretching from the core of the Milky Way in Ophiuchus to the Rho Ophiuchi cloud complex, the Blue Horsehead Nebula and many other deep-sky objects (incl. a part of Scorpius with a.o. Antares) .

It's probably one of my most ambitious & difficult astro-imaging projects to date.

All data was acquired with CHI-5 (Nikon 200 F/2 and FLI ML16200 camera), (data from 11 advanced requests scheduled between May and the beginning of July)

Jarmo Ruuth’s Astro Mosaic Telescope Planner tool was used to calculate the mosaic coordinates for the different panels.

Astro Pixel Processor (APP) was used for registrating, integrating and creating the mosaics.

Min. 2 subs of 300s with LRGB were used for each panel. 10% overlap was chosen for the panels used in this mosaic.

Total integration time: 405 minutes.
LRGB 22:21:19:19 subs of 300s.

File size of the integrated images (for each color filter) was already 546Mb (about 140 Mpixels) and difficult to handle...
Therefore, I cropped, compressed (from 72 to 36 pixels / inch) & post-processed everything in Photoshop.

The final image covers a wide field of this MW area with a field radius of nearly 13 degrees (see sky map from Astrobin).