IC405, The “Flaming Star Nebula”

After imaging IC410, the next logical thing to image was its bigger companion, IC405. Known as the Flaming Star Nebula, it’s the other bright nebula within the hexagon of Auriga’s stars. The ripples at right are really nice (easily enhanced with LocalHistogramEqualization), but IC405 lacks the color contrast of IC410. The SII and H-alpha overlap … More IC405, The “Flaming Star Nebula”

LRGBCombination vs ChannelCombination for luminance data

Inspired by a recent thread on CloudyNights, I decided to reevaluate how I was using luminance data. I’ve never been fully happy with what I was getting. My typical approach has been to use LRGBCombination with the method suggested by Juan on the PI forums years ago. This has now become the accepted approach, it … More LRGBCombination vs ChannelCombination for luminance data

APOD: Comet ATLAS (C/2020 M3) and the Nebulae of Orion

I’ve been so busy writing and processing images that I haven’t even posted my recent APOD. We had two nice comets swing close to earth in November: Comet ATLAS (C/2020 M3) and Comet C/2020 S3 (Erasmus). Erasmus wasn’t very bright, but ATLAS M3 got up to around magnitude 7. More importantly, it went (from our … More APOD: Comet ATLAS (C/2020 M3) and the Nebulae of Orion

Empirical Evidence on Narrowband Filters with a Fast Telephoto Lens

[Updated with charts and 3 nm OIII data, 2 Dec 2020] Fast focal ratios and narrowband filters are known not to mix well. This is because light arriving at a steep angle to a glass filter will have its wavelength shifted. The faster the focal ratio, the steeper the light cone, and thus at some … More Empirical Evidence on Narrowband Filters with a Fast Telephoto Lens