Star Trails
🔭
Askar FRA400
📷
ZWO 2600MC Pro
🌃
Bortle 8
⏱️
6 hours
🗓️
April 2021
Overview
The Earth’s rotation causes the Sun to appear to move across the sky during the day, and the same motion applies to the stars at night. In a long exposure, this apparent movement is revealed as star trails rather than fixed points of light. This image shows stars circling the North Celestial Pole over a six hour period, tracing smooth arcs across the sky. The brightest trail belongs to Polaris, the North Star.
Background
My original aim for this photo was to track Polaris, but my mount couldn’t quite achieve that angle. So I changed the plan and went for a more conventional startrail image instead.
I told my ASIAIR PRO to target Polaris, and once it got as close as it could, I turned the mount off so that it wouldn’t track. I then took 2-minute exposures for six hours, and integrated them in PixInsight. The resulting image isn’t actually that far off the end result.
Most of the editing was done in Lightroom. This was mostly playing about with the contrast and saturation. I needed to clone out some hot pixels too — probably because I messed up a setting with the original PixInsight integration.
Urban Astrophotography art gallery
Images from my astrophotography projects are available as fine art prints and framed pictures.
Science
It’s a common misconception that Polaris is directly over the North Celestial Pole. Even some astroimagers think this. Polaris is close, but in a telescope view like this you can see that Polaris moves over the course of a night too.
Imaging details
- Total exposure
- 6 hours
- Dates captured
- 21 April 2021
- Location and sky
- Bristol, UK (Bortle 8)
Equipment and software
- Telescope
- Askar FRA400
- Camera
- ZWO ASI 2600MC Pro
- Mount
- Orion Sirius EQ-G
- Guiding
- None
- Control
- ASIAIR PRO
- Software
- PixInsight, Lightroom
- Image by
- Lee Pullen
Exposure by filter
No filter
- Channels
- RGB
- Subframes
- 180 × 2 minutes
- Integration
- 6 hours
View subframe and stack
Single subframe and integrated stack, both with a simple stretch applied.
Kit list
This is the equipment I used to capture the image.
Affiliate links help support the site at no extra cost to you.
Telescope: Askar FRA400
Read my review
Buy from Astroshop.eu
Buy from High Point Scientific
Camera: ZWO ASI 2600MC Pro
Read my review
Buy from Astroshop.eu
Buy from High Point Scientific
Control: ASIAIR Plus
Read my review
Buy from Astroshop.eu
Buy from High Point Scientific
Book an online Masterclass
Book a one-to-one Masterclass tailored to your skill level and equipment, with a practical focus on improving results even under light-polluted skies.
Seestar S50 image
Seestar S50 telescope coming later…
Donate
If you’ve found this content useful, please consider donating to help support the site!
Payment options load when this section is in view. Use the donation page
Discover more from Urban Astrophotography
Subscribe to get the latest posts sent to your email.
1 thought on “Star Trails”