|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
ASTRO: Three small PN: NGC 6884, IC 5217 und "Footprint" Nebula
In the nights when I collected the data for Abell 80 (http://ccd-astronomy.de/temp12/Abell80colourneugut.jpg) the seeing was quite good, so I imaged some small but bright planetary nebulae in between.
All three pictures were taken on my Berlin rooftop terrace with a 10" Meade ACF at 2050mm focal length on G11 mount and ASI1600MMC camera. With the small pixels of the ASI1600 I get an image scale of 0.38"/pixel. I show the pictures in 100% size, even if it's not always crisp and sharp. These small nebulae cannot be downsized any more if they should be larger than hot pixels. I had some difficulty with the enormous dynamic range of these objects. The stars had to suffer a bit in order to show the nebulae in a reasonable way. All three images consist of approximately 80-120 images at three seconds per channel. IC 5217 is a pure RGB, the other two are LRGB. I didn't sort the images by hand but combined them all with sigma stacking. NGC 6884 in Cygnus had the best seeing. Despite the large image scale the stars in the unprocessed stacks looked nice sharp. NGC 6884 is a quite "normal" planetary nebula, it is similar to NGC 6826 and has an outer halo which in my picture it was only seen by extreme stretching of the blue channel and didn't make it into the colour image. IC5217 in Lacerta has a very unusual shape. It has two bright centers and is rectangular in shape. The most famous of the three nebulae is certainly the Protoplanetary Nebula Minkowski 1-92, better known as "Minkowski's Footprint Nebula". Just like the "Egg Nebula", the footprint is a bipolar nebula. Unfortunately, the seeing was not quite as good here.
__________________
Stefan |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
ASTRO: LDN 778, LDN 782, reflection nebula GN 19.24.6 and a "few"stars | Rick Johnson[_2_] | Astro Pictures | 2 | January 22nd 14 07:11 AM |
ASTRO: NGC 6302 (the "bug nebula") | Stefan Lilge | Astro Pictures | 3 | July 8th 11 08:07 PM |
ASTRO: Recently discovered "Cygnus Bubble Nebula" in Halpha | Richard Crisp[_1_] | Astro Pictures | 2 | September 9th 08 09:54 PM |
ASTRO: NGC 6888, The "Crescent Nebula" in Cygnus | George Normandin[_1_] | Astro Pictures | 2 | October 25th 07 03:40 AM |
ASTRO: NGC 6888, The "Crescent Nebula" in Cygnus | George Normandin[_1_] | Astro Pictures | 3 | October 25th 07 03:19 AM |