The Iris is a reflection nebula, a cloud of gas and dust illuminated by a central star. It is six light-years across, and lies 1400 light-years from Earth. Its official name is LBN 487, while the stars clustered nearby are called NGC 7023.
Version 2, reprocessed December 2022
From the Reprocessing Bonanza 2022. This version uses exactly the same data as version 1, but with better processing tools and skills. I spent a lot of time processing this image the first time around! I remember being happy at getting so much detail despite my city centre location. This new version has much tighter stars that emphasises the faint nebulosity.
Version 1, April 2021
This target was a challenge I set myself. Conventional wisdom is that light pollution wipes out The Iris Nebula, so it’s pointless trying to image it from a city. Maybe a modern camera coupled with a long integration time could manage it?
I’m happy with the result, especially considering how much I needed to crop in given my telescope’s short focal length. See the sample data images at the bottom to see just how small The Iris appears in my frame. It’s nothing short of remarkable that the dust clouds surrounding the nebula are visible, blocking the light from background stars.
It did take 20.5 hours of integration time to get to this stage, however. Darker skies would definitely make this an easier target! Just the fact that it’s achievable from a city is kinda mind-blowing though.
* April 2021
* Bristol, UK (Bortle 8)
* Telescope: Askar FRA400 f/5.6 Quintuplet APO Astrograph
* Camera: ZWO ASI 2600MC-PRO
* Mount: Orion Sirius EQ-G
* Guide: William Optics 32mm; ZWO ASI 120MM Mini
* Software: PixInsight, Photoshop, Lightroom
* Control: ASIAIR PRO
* 615 x 120 seconds
Total integration time: 20.5 hours
By Lee Pullen
Example source data
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