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Subject
IC 5070
Date
30th June 2003
Telescope or Lens
Vixen ED102SS
Mount
GP DX
Camera
SXV H9
Filters
Schuler 10nm Ha
Total Exposures L 24 min R   G   B  
Sub exposure

6 frame mosaic each 2 x 2 min

Binning
Luminance 2 x 2
Field of view and resolution
Approx 1.14 x 1.36 Degrees. 4 Arcsec / Pixel
Comments  
Pelican Nebula. Mosiac of six frames.

Each individual image was bias subtracted and filtered with median 3x3 5%. The images for each frame of the mosaic were then added to give six master images. These were then saved as bitmaps. The mosaic was assembled in Adobe Photoshop. The top left image was used as the base and the canvas size expanded to accommodate the other five frames. Each image was cropped to leave a small overlap, then cut using a feathered border and pasted to a new layer on the original image canvas. Each individual frame was positioned by reducing the opacity to see the underlying image and by moving, skewing and rotating as required to get the best alignment. Finally the opacity was returned to 100% before moving on to the next frame. Once all the components were in place, each individual layer was manipulated using brightness, contrast and curves to match and hid the joins. The layers were then flattened and final contrast and brightness adjustment carried out. This was a brief exposure to plan for a better shot in the near future. The overlaps were quite large, resulting in inefficient use of the field of view.