alan4908

Thanks ! Alan

Thanks - glad that you liked the end result. (I discovered that I had a red glow around all my stars due to my FWHM of my red channel stars being much larger than the other colour channels. This was due to the fact that I acquired the majority of the subframes in non ideal conditions. However, I corrected for this effect by eroding the red channel through a star halo mask) Alan

Thanks for the comment Graham - good luck with your capture. Beware that it has a small apparent size, I was imaging at 0.7 arc seconds/pixel but even at that level I decided to crop the image down to focus the viewers attention on the cluster. Alan

Discovered in 1788 by William Herschel, NGC 2419 is one of the most massive and brightest globular clusters but appears as a dim 9th Magnitude object due to its large (275,000 light years) distance from Earth. The bright blue star to the left of NGC 2419 in the image below is HD60771, which is much closer, being only 350 light years distant. In 1944, the American astronomer named it the “Intergalactic Tramp”, since it was once (erroneously) thought not to be orbit around our galaxy but rather wandering the space between Earth and the even more distant galaxies. More recent observations have confirmed that although NGC 2419 is very distant, it is still trapped by our galaxy’s gravity well, taking 3 billion years to complete an orbit. The orbit places it even further away that the Milky Way’s most famous satellite, the Large Magellenic Cloud and even further away that the Small Magellenic Cloud. The image below was taken with my Esprit 150 and represents 11.3 hours integration time. Alan LIGHTS: L:23, R:22, G:10, B:13 x 600s, BIAS:100, DARKS:30, FLATS:40 all at -20C.

Thanks for the comment Thanks. Thanks Peter - I think I prefer the colour in this reprocess of the ED 80 data - this time I used Pixinsight's Photometric Colour Calibration process. Alan

Whilst waiting for clear weather, I decided to reuse some data that was previously acquired by my Skywatcher ED80 and my Esprit 150. I used the Esprit data to get maximum detail on M106 and its companion NGC4248, whilst I reprocessed the ED 80 data such that the resultant background showed very faint objects. The ED 80 data is LRGB whilst the Esprit data also contains a Ha blend into the red channel. On the processing side, I used RegiStar to align the Esprit 150 and ED 80 images and then used Pixinsight's Gradient Mosaic Merge to create a seamless image. Alan M106 M106 (annotated)

Here's five of my favorites from 2020, all taken with an Esprit 150 and a SX Trius 814. Alan NGC3718 NGC4725 NGC6995 Vdb152 M94

Thanks - I don't think I could have done this without an automated set up. Thanks Martin ! I'm fortunate to live at a location which (by UK standards) has very good dark skies. I'm also at the top of a hill which helps, although it does get rather windy at times.

My image generating productivity has been significantly decreased by the poor UK weather in recent months. Even with an automated observatory, my image capturing has been moving at a glacial rate. However, here’s the latest image to finally emerge from my set up – NGC 7497 NGC 7497 is a spiral galaxy in the Pegasus constellation, approximately 60 million light years distant with a disc size of approximately 91000 light years. The galaxy shows signs of warping indicating past interactions. You can (just) make out some HII regions in the image below that appear to be semi-randomly positioned within the galaxy. The galaxy is viewed away from the plane of our own galaxy, through a mass of dust and gas known as Integrated Flux Nebula (IFN), which resides in our own galaxy and is approximately 600 light years distant. The stars within our galaxy act together in an integrated fashion to faintly illuminate the gas, hence the name. In 1985, the astronomers Magnani, Blitz and Munday (MBM), decided to catalogue the various IFNs and the one shown is known as MBM 54. The image also features many stars and a several background galaxies. Some of the stars are closer to Earth than MBM 54 and appear sharp and distinct (eg the bright blue star at the top, middle) and some are more distant. The more distant objects will therefore appear fuzzy if they are viewed though dust and nebulosity. The LRGB image below represents just under 16 hours integration time and was taken with my Esprit 150. Alan LIGHTS: L:37, R:20, G:20, B:18 x 600s, DARKS:30, BIAS:100, FLATS:40 all at -20C.

A second attempt at the Witch’s Broom Nebula (NGC6960), this time in narrowband. It took me 3.5 months to acquire the data, which was caused by a combination of poor UK weather and the partial obstruction by trees at my location. Anyway, better late than never.... Although imaged in narrowband, I tried to go for realistic looking colours so started with Ha mapped to red and OIII mapped to blue with a synthetic green generated from a Ha/OIII mix. After a few hue adjustments, I ended up with a colour image which mainly gave blue/reddish stars and nebula. I found that detail could be boosted by creating a super luminance image from the individually stacked narrow band stacks and then deconvolving the result which I then blended into the colour result via Pixinsight’s LRGB process. The image below was taken with my Esprit 150 and represents 16.5 hours integration time. LIGHTS: Ha: 15, OIII: 18 x 1800s; DARKS:30, BIAS:100, FLATS:40 all at -20C.

NGC 896 is an emission nebula located in Cassiopeia about 7500 light years away. It is also the brightest part of the Heart Nebula (IC 1805) but has a separate classification, since it was the first part of the nebula to be discovered. The dominant red colour arises from hydrogen line photon emissions created by intense ultraviolet emissions from nearby stars. It is a star forming region and also home to many dark lanes created by interstellar gas. Some very bright blue stars compete in the nebula illumination, resulting in a blue/red cast in certain parts of the image. The LRGB image has an Ha blend into both the red and lum channel and was taken with my Esprit 150. It represents 18.5 hours integration time. Alan LIGHTS: L:22, R:18, G:11, B:12 x 600s; Ha: 16 x 1800s. DARKS:30, BIAS:100, FLATS:40 all at -20C.

Thanks for the comment Andrew. In terms of the colour balance, I was drawn to change this when I checked the histogram levels which shows that the original image is quite unbalanced at the lower levels, however, I also like the "more blue" effect in the original. I I think the credit for the framing goes to CCDNavigator (where you can preview the image for your given FoV) and ACP, for actually getting the object in the center of the FoV. As an aside, CCDNavigator was recently made compatible with ACP Expert which enables you select objects to image through a view mouse clicks, which I really like. Thanks Paul ! Alan

Hmmm - I decided that the RGB background levels are not optimal on these images and so applied PI Background Neutralization tool to make them a little more balanced.

Located in the Cygnus constellation about 6000 light years distant, NGC6914 is a blue reflection nebula consisting of VbB131 and VdB132. Surrounding NGC6914 are reddish areas of hydrogen emission nebula which provide a dramatic colour contrast to the blue nebulosity. The contrast is further increased by regions dark nebulosity (LDN 899). The stars are also a notable feature of the image since embedded within the nebula is the star cluster Cygnus OB2 which consists of about 100 class “O” (yellow) and 2500 class “B” (blue-white) stars. The image was taken with my Esprit 150 and represents 16.5 hours integration time. It is an LRGB image with a Ha blend into both the Red and Lum channels. Alan LIGHTS: L:21, R:17,G:12, B:16 x 600s; Ha:11 x 1800s. DARKS:30, BIAS:100, FLATS:40 all at -20C.

Thanks Glad you liked it - it is a pity that it doesn't appear a little more often here. Thanks Noddy - yes, it is quite amazing what the brain sees when you star at nebula's for a while....