First light with Borg 72FL

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Object: NGC7000 and IC5070
Observation site: Sandsli, Norway, Bortle class 6
Date: 2022-08-29 - 2022-08-30
Moon phase: ca 10%
Outside temperature: Ca +15° C
Telescope: Borg 72FL with Starizona Apex ED S 0.65x reducer
Focal length: 260mm
Camera: ASI1600MM-Pro
Filterwheel: ZWO EFW
Filters: Antlia - 3nm Narrowband and LRGB Filter Set - 31mm Unmounted - Pro Version
Mount: Skywatcher AZ-GTi mount in equatorial mode
Guidescope: Artesky 30/130mm
Guidecam: ASI120MM mini
Focuser: More Blue with ZWO EAF
Cooling: -20° C
Gain: 139
Exposure:
Ha: 23 x 240s
O: 23 x 240s
S: 23 x 240s
Total integration time HSO: 6h 08m
Darks, Flats and Bias.
Sequence control: AsiAir Plus
Stacking and image processing: Astro Pixel Processor, Photoshop CC, Ligthroom Classic

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Correct backfocus should be 60mm according to Starizona, so I started with a physical backfocus of 59.5mm to allow for the 0.5mm extension produced by the filters.
The image above has a very slight elongation of the stars towards the corners, indicating too short backfocus. Only visible by pixel peeping.
So for the next imaging session (the Clamshell nebula) I added a 0.5mm spacer ring. With this I got nice round stars all the way to the corners, as shown in the 1:1 crop image below:

The picture is taken from Sandsli, Norway, 30-08-2020. using the same setup as above.

Finished picture shown below:

 

The picture is taken from Sandsli, Norway, 30-08-2020.

Object: SH2-119 (Clamshell Nebula)
Observation site: Sandsli, Norway
Date: 2022-08-31 and 2022-09-02
Moon phase: Less than 35%
Outside temperature: Ca +15° C
Telescope: Borg 72FL with Starizona Apex ED S 0.65x reducer
Focal length: 260mm
Camera: ASI1600MM-Pro
Filterwheel: ZWO EFW
Filters: Antlia - 3nm Narrowband and LRGB Filter Set - 31mm Unmounted - Pro Version
Mount: Skywatcher AZ-GTi mount in equatorial mode
Guidescope: Artesky 30/130mm
Guidecam: ASI120MM mini
Focuser: More Blue with ZWO EAF
Cooling: -20° C
Gain: 139
Exposure:
Ha: 30 x 240s
O: 28 x 240s + 9 x 480s
S: 19 x 240s + 1 x 480s
Total integration time HSO: 6h 28m
Darks, Flats and Bias.
Sequence control: AsiAir Plus
Stacking and image processing: Astro Pixel Processor, Photoshop CC, Ligthroom Classic

 

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The Telescope rig.

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© 2008: Odd Høydalsvik