I recently acquired the 0.7x focal reducer from Celestron for the 8-inch EdgeHD SCT. Once I got the proper backfocus with the QSI 583wsg camera and a Starlight Xpress AO unit, I was very pleased with the shape of stars throughout the entire image frame.
We have had several beautiful nights recently with clear skies, a steady atmosphere and wonderful transparency so I took advantage of the great conditions to put the focal reducer through it paces. The resulting image, an HaRGB image of the Horsehead Nebula:
The image is composed of 6 hours of 15 minute RGB subexposures and 6 hours of 30 minute H-alpha subexposures using AstroDon filters.
I hope you enjoy both the HaRGB and H-alpha images of the magnificent Horsehead Nebula.