California Nebula

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timc

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Feb 1, 2025, 8:21:47 AMFeb 1
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An image of the California Nebula (NGC 1499, Sh2-220), an emission nebula in the constellation of Perseus.  The name comes from its apparent resemblance to the state of California. It lies about 1,000 light years away from us and is large, with a length of approx. 2.5 degrees of sky, but it is very dim.  However, using a Ha filter its structure becomes apparent due to excitation of hydrogen in the nebula by the very energetic nearby star Xi Persei (also called Menkib). This image consists of L 15x300s unbinned, R and B 19x300s, G 18x300s and Ha 39x300s all binned x2 giving 9 hours and 10 minutes of total imaging time over 6 nights between 19 February 2023 and 10 March 2023.  I used a Takahashi FSQ85 ED (3.5 inch) refractor with focal reducer operating at f/3.9 mounted on a Paramount MX, a QSI 690 CCD camera and Lodestar guide camera.  Image capture was done with Maxim DL and I used CCD Stack2, Photoshop CS5 and Topaz Labs Denoise AI for further processing.  Thanks for looking.

Tim C

NGC 1499 California Nebula BB+Ha Tak85 FR QSI690 Feb 2025 Final.jpg

trevsie7

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Feb 1, 2025, 3:54:55 PMFeb 1
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Tim, that's a very nice image, it looks almost three dimensional.


On Sat, 1 Feb 2025, 13:21 timc, <tcos...@gmail.com> wrote:

An image of the California Nebula (NGC 1499, Sh2-220), an emission nebula in the constellation of Perseus.  The name comes from its apparent resemblance to the state of California. It lies about 1,000 light years away from us and is large, with a length of approx. 2.5 degrees of sky, but it is very dim.  However, using a Ha filter its structure becomes apparent due to excitation of hydrogen in the nebula by the very energetic nearby star Xi Persei (also called Menkib). This image consists of L 15x300s unbinned, R and B 19x300s, G 18x300s and Ha 39x300s all binned x2 giving 9 hours and 10 minutes of total imaging time over 6 nights between 19 February 2023 and 10 March 2023.  I used a Takahashi FSQ85 ED (3.5 inch) refractor with focal reducer operating at f/3.9 mounted on a Paramount MX, a QSI 690 CCD camera and Lodestar guide camera.  Image capture was done with Maxim DL and I used CCD Stack2, Photoshop CS5 and Topaz Labs Denoise AI for further processing.  Thanks for looking.

Tim C

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drja...@aol.com

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Feb 2, 2025, 5:26:10 AMFeb 2
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Brilliant Tim.  A great field of view and more muted Ha red that shows up the details much better.  Maybe the RGB data helps with that.

James


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On 1 Feb 2025, at 13:21, timc <tcos...@gmail.com> wrote:



An image of the California Nebula (NGC 1499, Sh2-220), an emission nebula in the constellation of Perseus.  The name comes from its apparent resemblance to the state of California. It lies about 1,000 light years away from us and is large, with a length of approx. 2.5 degrees of sky, but it is very dim.  However, using a Ha filter its structure becomes apparent due to excitation of hydrogen in the nebula by the very energetic nearby star Xi Persei (also called Menkib). This image consists of L 15x300s unbinned, R and B 19x300s, G 18x300s and Ha 39x300s all binned x2 giving 9 hours and 10 minutes of total imaging time over 6 nights between 19 February 2023 and 10 March 2023.  I used a Takahashi FSQ85 ED (3.5 inch) refractor with focal reducer operating at f/3.9 mounted on a Paramount MX, a QSI 690 CCD camera and Lodestar guide camera.  Image capture was done with Maxim DL and I used CCD Stack2, Photoshop CS5 and Topaz Labs Denoise AI for further processing.  Thanks for looking.

Tim C

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<NGC 1499 California Nebula BB+Ha Tak85 FR QSI690 Feb 2025 Final.jpg>

William Bottaci

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Mar 8, 2025, 5:38:22 AMMar 8
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Hello Tim, a very nice image, you captured it well.

Nearby star Menkib, which I'm glad you included, is massive, about 30 solar masses (star masses don't vary much so it doesn’t sound heavy but it's a rare heavyweight) and very hot, in fact one of the hottest stars that at mag +4 can be seen with the naked eye.

For anyone unfamiliar with binning, and it's not the word I would have chosen, it's where the camera, instead of addressing individual photodiodes instead groups a square of 2x2 or even 3x3 to act as one, thus increasing the light/sensitivity. It's at the expense of resolution but for objects such as nebulae there's not much detail you're going to notice the loss of.

Once again, you have envious equipment, software, and your processing from beginning to end all shows.
Thank you for sharing.
William




On Sun, 2 Feb 2025 at 10:26, 'drja...@aol.com' via croydonastro <croydo...@googlegroups.com> wrote:
Brilliant Tim.  A great field of view and more muted Ha red that shows up the details much better.  Maybe the RGB data helps with that.
James



On Sat, 1 Feb 2025 at 20:54, trevsie7 <trevs...@gmail.com> wrote:
Tim, that's a very nice image, it looks almost three dimensional.



NGC 1499 California Nebula BB+Ha Tak85 FR QSI690 Feb 2025 Final.jpg
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