This image of Venus in Ultra Violet light was captured on the morning of the 23rd June – the same morning that I captured my first Mars of 2009 and Jupiter with the NEB Upheaval. It was a busy morning!
The colours reveal some albedo differences in the cloud tops on Venus, and come from a combination of using a Schuler UV filter for capturing the luminance (detail) data, and processing the image as a false-colour composite using colour data from the RGB channels as well as the UV channel.
The seeing was only average, and Venus was at a respectable 30° altitude – shining brilliantly at mag -4.18.
Continue reading for more information about the capture and processing.
I captured the image with my 12″ Newt on the EQ6, with the DMK21AU04 and 5x powermate at about 6:30am local time. The UV data was captured at 15fps for approx 2 minutes giving me about 2000 frames. RGB data was captured at 60fps with a shutter speed of about 1/1000s and gain at about 800 (approx 80%) for about 60 seconds in each channel, giving me 3000 frames in each channel.
The separate channels were processed independantly in Registax 5, and the LRGB composite was made in Photoshop, where the UV channel made up the luminance data (giving the contrast) with the colour coming from the combination of R, G+UV/2 and UV making up the RGB.
I’m still waiting for a morning of great seeing to capture an excellent image of the cloud tops on Venus – but with the Sun not rising until 7am (well after the time I’ve had to go to work), it limits my opportunities at this time of year. Venus is on its way back towards the Sun over the next 5 months, heading for inferior conjunction in December, so hopefully I’ll get a few more chances before Venus dips too low.
Thanks for looking.