AMATEUR ASTRONOMY PAGES
Javier Gómez Laina                                                
                                                                                Abell 21  -  Medusa Nebula
(click on the image for a larger size - 414 Kb)

            

Object:             PK 205+14.1  -  Planetary nebulae in Gemini    
Telescope:       COMELLAS-2  telescope (250 f/5.4 Newton) TV Paracorr, LPS & H-alfa filters.
Camera:           Canon 350d  modified (infrared filter removed)
Exposures:       RGB:   87 x 300"   (7:15 total exposure)  ISO 400
                        Halfa:   50 x 400"   (5:33 total exposure)  ISO 800
Resolution:       0.97"/pixel  (largest size)
Date:                11 - 24 Mar 2007
Guiding:           MX716 on 2x barlowed TV-76
 

Processing:

Bias, Darks & Flat calibration
SDMask combining
Dynamic Background Extraction (sky gradient correction)
Histogram and Curves adjust


Software:
ImagesPlus, PixInSight, PhotoShop.