On approach to 'inferior conjunction' Venus is now a large, thin crescent, oriented horizontally - a rather strange angle for such northern latitudes and disappearing rapidly into the twilight. I dashed out to a local field with my brother and got about 40 very rapid snaps straight down my 8" SCT using a 2x barlow lens (f.l. ~ 3.9m). It's amazing how bright it still was considering how thin the crescent phase was, which by the way was easily seen in 10x binoculars and not quite by eye. I could see a fine backlit lower edge to the globe at 200x, seething in the low atmospheric turbulence and its brilliant white colour was dispersed into a near perfect spectrum. I stacked the best 17 of the 1/500" pictures (ISO 1600) and got a beautifully smooth rainbow crescent. Whilst this looked wonderful I had to use the RGB realign tool in Registax to shift the blue down and red up by 8 pixels to get a much sharper white crescent. Here's the final imaged cropped to a 500x500 bitmap.
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