Optec Lepus 0.62x Focal Reducer Testing

6 - 10 minute exposures per channel with the QSI 583wsg (monochrome) CCD, unbinned; camera temp -10C. Astrodon Tru-Balance Generation 2 E-Series - LRGB 1.25" filter set.

Telescope configuration: EdgeHD 1100 (2800mm, f/10) with the Optec Lepus 0.62x focal reducer, yielding 1848mm, f/6.6, an image scale of 0.60 arc-seconds/pixel and a 25.1 x 33.4 arc-minute FOV. Mount: Losmandy G11 w/Gemini. Focused using a Bahtinov focus mask.

Post processing: calibration using 15 dark frames, 3 bias frames and 3 flat frames per channel; aligned and min/max excluded average combined in ImagesPlus 4.25. DDP and curves in Nebulosity2; Color aligned and combined; Adaptive Richardson-Lucy deconvolution 5x5 x 5 passes, color adjustments in ImagesPlus 4.25. Background smoothing, saturation and final color adjustments in IP. Unsharp mask then resized to software bin 2x. Autoguided with a Starlight Xpress Lodestar connected to the integrated guideport of the QSI 583wsg and controlled by PHD autoguiding software.

A special note of thanks to W. Henner Fahrenbach, Andrea Tasselli and Sam Bruce for their considerable assistance in diagnosing and resolving several issues in the process of testing the focal reducer and to Mike Unsold for help in color adjustments using ImagesPlus.

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