Saturn near opposition showing Seeliger effect
A terrible night for imaging (19 July) - rain a few hours before, high winds, 95% cloud cover, why did I bother? Well, I've never seen the Seeliger effect before, so I set up at 10:30, arranged some ice packs on the back of the OTA and hoped that the rain would stay away for an hour or two.
I finally got a 2.5 minute break in the clouds (of which about half of that was useful), blasted away with the camera and hoped for the best. The image below shows a soft, but bright rendition of the planet near opposition, compared to one I took a few weeks ago in better seeing conditions with exactly the same capture settings and processing applied. The first time I made this image I didn't believe the result, so I did it again, making sure that processing applied between images was identical.
Andrew
Image details: Celestron Evolution 9.25" SCT @ f21.0 with 2.5x TV PM, ASI 224MC, 7500 frames stacked in AS!3, sharpened in Registax, final touches in Photoshop Elements, shown at 150% captured size.
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