I managed to get out last night in a suitably dark sky for the first time in over two months. Fortunately, all the kit still seemed to be working! I didn’t try anything too difficult – just my annual shot of M27 (18 x 5 min) and a quick go at open cluster NGC6940 in Cygnus (7 x 5 min). Both through the 190MN with the Atik 460.
I’ve just acquired Baader OIII and SII filters to go with the 7nm Ha filter I already had, and grabbed a few minutes of clear sky last night to try them out. I know I’ve spent a bit of time on M27 recently, but as it was high in the sky, and nice and bright, I thought I’d give it a shot. The first image is one that was created using just 2 x 2min exposures with each filter, and then combining them using the Hubble palette: R=SII; G=Ha; B=OIII.
There’s virtually no SII response from M27, hence the blue-green colouration. Another common way of displaying narrow band images is to use Ha for the red channel, OIII for the blue channel, and an average of Ha and OIII for the green channel. This gave the following image:
I shouldn’t have really, because it’s such a common subject, but I couldn’t resist another go at M27. This is an RGB image through the ED-80, comprised of just 5 x 2min each of R, G and B frames, processed in ImagesPlus, with a couple of small diffraction spikes added using Noel Carboni’s Photoshop actions.
Last night’s target was M27, the Dumbbell Nebula in Vulpecula. This is a much photographed object, because it’s so big and bright, but this was the first time I’d had a go with the Atik. This image is taken from 10 x 2min luminance exposures through the CLS filter, and 10 x 1min each for RGB. It was taken through the LX200 without the focal reducer attached.
At the end of the session I decided to try a shot through the hydrogen alpha filter, and took a single 5min exposure. I used this as the luminance frame, along with the RGB frames from above, and the result is shown below, and gives a slightly different perspective on the structure of the nebula.