| Object : | M97, Owl Nebula |
| Coordinates/Direction : | center of image, RA 11h15m, Dec +54 55' |
| Object size : | 202" by 196" |
| Object magnitude : | 9.9 |
| More to know : |
Wikipedia:
https://en.wikipedia.org/ wiki/ Owl Nebula |
| Date : | 2023-10-13 |
| Time (UT) : | 00:07 - 01:17 |
| Mount : | SkyWatcher HEQ5 controlled by Astroberry |
| Guide : | Ekos internal guider in dithering mode, QHY5 camera with 200 mm f/3.5 lens |
| Lens/telescope : | Pentax 645 300 mm ED f/4 (medium format lens) |
| Corrector/Barlow : | - |
| Field (FOV) : | 6.8x4.5 degree, before cropping |
| Filter : | none |
| camera : | Canon 6D, controlled by Astroberry software |
| Film/CCD : | Raw |
| Exp. time : | 44x60 seconds, iso1600 |
| Image process tool : | Siril, Gimp, Irfanview |
| Processing : | cal bias, flat and astro metric color calibration |
| Weather : | Thin clouds 25% during night |
| Site : | Sweden, Stockholm, Hagsätra. Bortle class 9 |
| Comment : |
Planetary nebulas are small objects, a few arc minutes wide.
It's preferable to have long focal lengths, 2000 mm or so. In this case I use my 300 mm lens.
Other exciting objects can be identified on this plate solved image: M97 Astrometry. |
| Date : | 2023-10-13 |
| Time (UT) : | 00:07 - 01:17 |
| Comment : |
Zoom in at 2x on the cropped image and crank up the color saturation.
The color is easy to see but very noisy.
A 3 hour exposure had been better.
Planetary nebulas is the left over from an exploded star, the stars particles are like a big cloud where the once was.
Compare with photos below taken with different focal lenghts. |
| Date : | 2020-01-22 |
| Time (UT) : | 20:32 - 22:40 |
| Mount : | EQ6 Synscan and EQMOD controlled |
| Lens/telescope : | TS130, 910mm f/7 |
| Corrector/Barlow : | Altair 3" field flattener 1x |
| Field (FOV) : | 2.25x1.5 degree, before cropping |
| Filter : | none |
| camera : | Canon EOS 6D, controlled by APT software |
| Film/CCD : | Raw |
| Exp. time : | 60 x 60 seconds + 16 x 120 seconds at ISO1600 (HDR) |
| Image process tool : | AstroImageJ, Fitswork, Irfanview |
| Processing : | Flat calibrated, high contrast, gamma 5, level, color, noise filter |
| Weather : | Clear sky |
| Site : | Stockholm, Sweden, Hagsätra. Bortle class 9 |
| Comment : |
This night the sky was darker than what I normally have. See how the noise goes down.
This is the whole field that the telescope deliver to a full frame camera, 3 x 2 degrees, as you see the planetary nebula is very small.
The image consist of two different exposures times to achieve a better dynamic, HDR photo. |
| Date : | 2020-01-22 |
| Time (UT) : | 20:32 - 22:40 |
| Comment : |
Zoom in on the M97 Planetary Nebula and the galaxy M108.
The back ground is much better this time, less light pollution and a noise filter applied in the image process. |
| Date : | 2019-01-20 |
| Time (UT) : | -- |
| Mount : | EQ6 Synscan and EQMOD controlled |
| Lens/telescope : | TS130, 910mm f/7 |
| Corrector/Barlow : | Altair 3" field flattener 1x |
| Field (FOV) : | 2.25x1.5 degree, before cropping |
| Filter : | none |
| camera : | Canon EOS 6D, controlled by APT software |
| Film/CCD : | Raw |
| Exp. time : | 228x30 second ISO1600 |
| Image process tool : | AstroImageJ, Fitswork, Irfanview |
| Processing : | crop 1:1, resize, stretch, flatten |
| Weather : | Clear sky |
| Site : | Stockholm, Sweden, Hagsätra. Bortle class 9 |
| Comment : |
New test, this time I reduce the sub image exposure to 30 second and took 228 photos of the object.
It looks very noisy, better to try ISO 1600 or ISO3200 next time which give lower readout noise, but will also reduce the dynamic range a lot.
A telescope with a focal length of 2000 mm had also been good. |
| Date : | 2017-12-21 |
| Time (UT) : | -- |
| Mount : | EQ6 Synscan and EQMOD controlled |
| Lens/telescope : | TS130, 910mm f/7 |
| Corrector/Barlow : | Altair 3" field flattener 1x |
| Field (FOV) : | 2.25x1.5 degree, before cropping |
| Filter : | none |
| camera : | Canon EOS 6D, controlled by APT software |
| Film/CCD : | Raw |
| Exp. time : | 65x60 second ISO800 + 21x60 second ISO1600 (HDR) |
| Image process tool : | AstroImageJ, Fitswork, Irfanview |
| Processing : | crop 1:1, resize, stretch, flatten |
| Weather : | a bit foggy but otherwise clear |
| Site : | Stockholm, Sweden, Hagsätra. Bortle class 9 |
| Comment : |
My first image with my new setup with the 3" field flattener.
Not very big success with the cleaning of the sensor, no flat field calibration at this stage.
A planetary nebula is the left over from an old stellar explosion.
The galaxy upper right corner is M108. |
| Comment : |
With a noise filter and flatten of the background it looks like this |
| Date : | 2015-11-21 |
| Time (UT) : | -- |
| Mount : | EQ6 Synscan and EQMOD controlled |
| Lens/telescope : | TS130, 910 mm f/7 (682 mm, f/5.3) |
| Corrector/Barlow : | Riccardi flat field corrector 2.5" x0.75 |
| Field (FOV) : | 3x2 degree, before cropping |
| Filter : | none |
| camera : | Canon EOS 6D, controlled by APT software |
| Film/CCD : | Raw |
| Exp. time : | 22x60 second, ISO800 |
| Image process tool : | Fitswork, Irfanview |
| Processing : | crop, resize, stretch, flatten |
| Weather : | clear |
| Site : | Stockholm, Sweden, Hagsätra. Bortle class 9 |
| Comment : |
Three test photos with three different lenses and telescope. shot from my balcony, very light polluted sky.
A planetary nebula is the left over from an old stellar explosion.
The galaxy upper right corner is M108. |
| Date : | 2013-11-28 |
| Time (UT) : | -- |
| Lens/telescope : | Pentax 500mm f/4.5 |
| Field (FOV) : | 4.1x2.7 degree, before cropping |
| camera : | Canon EOS 5D |
| Film/CCD : | Raw |
| Exp. time : | 30x60 second, ISO1000 |
| Date : | 2013-11-25 |
| Time (UT) : | -- |
| Lens/telescope : | Pentax 165mm f/2.8 |
| Field (FOV) : | 12x8 degree, before cropping |
| camera : | Canon EOS 5D |
| Film/CCD : | Raw |
| Exp. time : | 25x30 second, ISO1000 |
English
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