Continuum image - filter incidence = 10 °

5 x 5s exposure
Pre-processing : dark and flat corrected
Processing : radial gradient removed + unsharp mask + log visualisation

Click here for alternate processing and visualisation

Processing : radial gradient removed + unsharp mask + log visualisation

Click here for alternate processing and visualisation

- 300 mm F/5.6 telephoto lens working at F/8,
- Motorized equatorial mounting (GP Vixen),
- Hi-sis 43 cooled CCD camera, KAF1600 detector (1536x1024 pixel), binning 2x2, 16 bits CAN,
- Andover interference filter :
            - 530.288nm at 0° incidence,
            - bandwith at 50% transmission = 0.483 nm,
            - bandwith at 10% transmission = 0.910 nm,
            - ghosts images caused by reflections in the filter (the 2 main ghosts images are about 1/100 intensity of main image).
           - click here for more information on filter transmission.
- click here for an image of this equipement

Image orientation : Celestial North is up (tilted 3.5° to the top right) - East to the left
Position angle of the sun North Pole = 353.1°
Sun diameter = 31.48 arcmn
Image scale = 12.4 arcsec/pixel (from sun diameter measurement)
SAO 77915 mag 4.18 star visible to the east on all images
Site location : Instituto Nacional de Petroleos (near Sumbe) S 11° 07' 31.8"    E 13° 55' 57.1" Altitude = 250 m

- All images registered to the sun to better than 0.2 pixel
- 15 dark images taken immediatly after 3e contact - 5 s exposure
- 15 flat images with filter incidence = 0° and 5 s exposure
- 15 flat images with filter incidence = 10° and 5 s exposure

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