Observation by Alun Halsey: Sunspot group AR4420 in Calcium K

Uploaded by

Alun Halsey

Observer

Alun Halsey

Observed

2026 Apr 25 - 12:41

Uploaded

2026 Apr 26 - 10:53

Objects

The Sun

Equipment

Helios 150mm f/8 refractor (stopped to 120mm)
Herschel Wedge
Lunt CaK yellow filter + Antlia 3nm filter + IR block
ZWO ASI678MM
Ioptron CEM60

Location

Reading Berkshire UK

Target name

The Sun

Title

Sunspot group AR4420 in Calcium K

About this image

Helios refractor with re-spaced objective lenses by 3mm and stopped down to 120mm. SER recorded in Firecapture and stacked/processed in Astrosurface, false colouring added in Inti Partner.

Files associated with this observation

Panorama.png (3.9 MB)

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