{"id":3682,"date":"2010-08-15T21:24:22","date_gmt":"2010-08-15T11:24:22","guid":{"rendered":"http:\/\/www.ayton.id.au\/wp02\/?p=3682"},"modified":"2010-08-19T15:19:19","modified_gmt":"2010-08-19T05:19:19","slug":"astrophotography-omega-centauri-globular-cluster-with-the-panasonic-gh-1","status":"publish","type":"post","link":"http:\/\/www.ayton.id.au\/wp02\/?p=3682","title":{"rendered":"Astrophotography – Omega Centauri globular cluster with the Panasonic GH-1"},"content":{"rendered":"

This week my friend and I took the opportunity of clear skies and no wind to brave the Winter cold and set up his computerised telescope mount and Williams Optics 4″ f\/7 refractor telescope.<\/p>\n

Just before the clouds came in, I managed to swap his Nikon D700 with my Panasonic GH-1 Micro Four Thirds<\/a> camera body, and without having time to check focus (and forgetting to switch to my usual RAW + JPEG), I managed to get one shot in.<\/p>\n

Thankfully, it was practically parfocal with his Nikon D700 and even though the GH-1 had twice the magnification as the full frame D700, the focus was very acceptable.<\/p>\n

I decided to shoot at ISO 3200<\/strong> despite knowing that my version of the GH-1 (being one of the first), suffers from severe banding noise at high ISO.<\/p>\n

Nevertheless, given the circumstances, I am very happy with this shot which was an unguided 60sec exposure at f\/7 with automatic dark frame noise reduction done in-camera<\/strong> and the only PS was levels to darken the background and minimise the banding, and, cropping and\u00a0 resizing for the web (no sharpening or NR in PS):<\/p>\n

I have always wanted to image this globular cluster as it has always amazed me at how many stars can be located in one cluster like this – just awesome!<\/p>\n

\"Omega<\/a><\/p>\n

The Nikon D700 having the same number of pixels but much larger photosites given the larger sensor, obviously had much less noise but was also at half the magnification – you can’t have everything!<\/p>\n

Unlike my Olympus dSLR which has Live Boost option for Live Preview<\/strong> which really helps visualise stars, the Omega Centauri at f\/7 was NOT visible in the GH-1 EVF or LCD, nor the D700 live view, and thus to focus accurately, I would have needed to find a brighter star or planet.<\/p>\n

The banding is an issue primarily with the early models of the GH-1, but most digital cameras, even the Canon 5D Mark II can show banding in shadow areas. It can be reduced using Nik Dfine software<\/a> – perhaps I shall buy it one day to try it out!<\/p>\n

More of my astrophotography can be found here<\/a>.<\/p>\n

And here is my friend’s Nikon D700 version which I think was a 4 minute exposure at ISO 1600 and thus has a lot more stars visible and the centre highlights are blown given the exposure was 4x the exposure<\/strong> of the above GH-1 exposure, and he did not need to resort to adjusting levels to remove banding:<\/p>\n

\"Nikon<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

This week my friend and I took the opportunity of clear skies and no wind to brave the Winter cold and set up his computerised telescope mount and Williams Optics 4″ f\/7 refractor telescope. Just before the clouds came in, I managed to swap his Nikon D700 with my Panasonic GH-1 Micro Four Thirds camera […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[93,18],"class_list":["post-3682","post","type-post","status-publish","format-standard","hentry","category-photography","tag-astrophotography","tag-four-thirds-micro"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t