| Object : | NGC 1499 |
| Coordinates/Direction : | RA: 04h03m, DEC: +36o25' |
| Object size : | 160' x 60' |
| Object magnitude : | 6 |
| More to know : |
Wikipedia:
https://en.wikipedia.org/ wiki/ California Nebula |
| Exp. time : | 256x60 seconds, iso1600, dithering mode |
| Image process tool : | Siril, Gimp, Irfanview |
| Processing : | cal bias, flat and astro metric color calibration |
| Weather : | clear |
| Comment : |
Added one more hour of exposure to the previous ones, more than 4 hours now. |
| Exp. time : | 196x60 seconds, iso1600, dithering mode |
| Image process tool : | Siril, Gimp, Irfanview |
| Processing : | cal bias, flat and astro metric color calibration |
| Weather : | clear |
| Comment : |
After collecting all photos I have of the California Nebula it summed up to 3 hour and 16 minutes exposure.
That will reduce the noise and make it easier to get out the nebula from the light pollution. Much better result now.
If I take new photos from a dark place it should even better.
The red radiation is the H-Alpha, it has the wavelength 656 nm, the is on the edge of the visual range.
A camera that has its IR cut filter removed will get its sensitivity for this wavelength increased by at least two times.
Should I do this IR modification on my old camera or buy a new real astrocamera ?
The first is free if I do it by myself, the other cost a lot. |
| Exp. time : | 60x60 seconds, iso1600, dithering mode |
| Image process tool : | Siril, Gimp, Irfanview |
| Processing : | cal bias, flat and astro metric color calibration |
| Weather : | clear |
| Comment : |
The California nebula is really big, its length is 2.5 degree, 5 times the Moon.
It's relatively bright too, magnitude 6.
I tested with a photo from the balcony if there is possible to see anything of it.
And yes it is, but need a lot longer exposure time than the one hour I took and I must be at a dark place too.
Processing these kind of objects is more tricky than normal star images, you must get rid of the background without erasing the nebula at the same time.
Something that I need to practize on. |
| Date : | 2023-10-07 |
| Time (UT) : | 20:22 to 21:37 |
| Comment : |
A crop around the nebula to see it more clearly.
The nebula is inside our Milky Way galaxy at a distance of 1000 ly.
It was discovered relatively late, 1884 by E. E. Barnard.
It emits its radiation at 656 nm and 486 nm.
Very difficult to observe visually, better with cameras and narrow band filter centered around these wave lengths. |
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