This is easily the best astro shot I’ve managed to date. Taken using a combination of the cross filter and the new didymium / red enhancing filter which really draws out the nebulosity in Cygnus. The North America nebula, Pelican nebula and Butterfly nebula can all be seen in this 1000 second (10×100 seconds) exposure.
I’ll probably try the same shot again, but without using the cross filter. I think it can work well in single exposures, but Deep Sky Stacker has a hard time with multiple exposures, and the effect gets a bit too distracting.
Details: Nikon D7000, Nikkor 50mm/f1.8 at f4. 16 minutes 40 seconds (10 x 100 seconds) at iso 800. Using cross filter and didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.
A few days later I had a go at imaging the North America nebula with the Nikkor 18-105mm/f3.5-5.6 lens. I accidentally took the photos as 70mm, so there isn’t much difference to the 50mm; just a lot less light gathering power!
Details: Nikon D7000, Nikkor 18-105mm/f3.5-5.6 at 70mm and f5.2. 18 minutes (12 x 90 seconds) at iso 1600. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.
Since purchasing the Nikkor 180 f2.8 lens I’ve had another go at the nebulosity in the Sadr region. I’ve been experimenting with ISO settings, taking this image at ISO 6400. However I think I’ll stick to lower ISOs in the future (1600 and below) as the results at higher ISOs begin to deteriorate.
Details: Nikon D7000, Nikkor 180mm f2.8 at f2.8. 7 minutes (14 x 30 seconds) at iso 6400. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.
Looking to test the newly improved ‘barn door’ tracker to its limit, I dusted off my old Sigma 75-200mm/f3.8 with 2x tele-converter. But with a hefty 600mm 35mm equivalent focal length, I was prepared for the worst.
After less than a minute of polar alignment, and unable to frame the shot through the viewfinder (due to an awkward angle), I pointed the camera vaguely in the direction of the Great Globular Cluster in Hercules, and opened the shutter for a 30 second shot. Without a watch to count the seconds, I manually moved the dial round, counting the seconds off in my head.
Checking the screen, to my amazement, there it was! Not only had I centred the cluster first time, but there were virtually no trails. I know the shot is pathetic compared to most, but for a home-made, hand guided barn door tracker, cobbled together for under £10, I was blown away by the result.
Shown here is a single 30 second exposure (iso 2000) without the didymium filter, giving it much more colour than the final stacked image.
Details: Nikon D7000, Sigma 75-200mm/f3.8 (at 400mm with 2x converter). 5 minute exposure (10 x 30 seconds) at iso 3200 with didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.