Saturn Images from Friday Night 29/5/2015
As Saturn is badly placed from my back garden thought I'd take the opportunity to get some images from Rosliston on Friday night as forecast was clear!!!!
Once set up took opportunity to view Venus , at half phase, then Jupiter, cloud bands visible as well as moons still a bit too light for good contrast, moon showed up well in gibbous phase plenty of craters on view, by this time Saturn was glimmering through the haze / cloud, considering all the forecasts I'd checked had said clear, no cloud , it was disappointing to have to dodge between the clouds but to get rained on just added insult to injury!! good job I'd brought the scope coat with me ( once a boy scout.....)
Used neximage5 to image Saturn, less than 20 deg altitude gives an awful lot of atmospheric disturbance as was obvious with the vsry wobbly image on screen and first image above is the best effort using just the camera and stacking 600 frames in Registax, RGB align tweaked and wavelets also in registax and final tweak and rotation on Photoshop 6.
Then tried x2 barlow, really showed the atmospherics as well as the effect on atmosphere on colour alignment as mentioned by Roger in his talk on the pd camera, slide 2 shows the processed image without any correction for this the red / blue fringes can be easily seen. Slide 3 shows correction of this in Registax using RGB align and the final image reduction of the effect using an Atmospheric Distortion Corrector(ADC) put in place before barlow lens, different orientation as camera went in at different alignment. Not the best images of Saturn, especially with the x2 barlow which not only magnifies the planet but also all the atmospheric distortions.