Barnard 150 is a dark nebula in Cepheus. It’s also known as the Seahorse Nebula. I don’t have any info on its size or distance so instead I’ll write about the challenge of showing detail when he nebula is just slightly darker than the background.

Normally we create contrast to making bright things brighter and dark things darker. That creates visual separation and carefully choosing where to put contrast is what can make or break an image. The problem here is that I couldn’t push the nebula down in level without losing detail in it–and there wasn’t that much to begin with! Instead I had to raise the overall level and then create contrast by pushing down the nebula. There was a lot of trial and error before I finally settled on a version I was happier with.

The other problem is that all astro images require “stretching’. Stretching is the process where we spread out the signal data to make it visible to our eyes. A lot of the art in astrophotography happens in the stretch since it’s the first place where we create contrast. The stretch required to bring out any detail in the dark nebula was intense. So intense it showed the limits o how effective the subframe calibration process is. Thankfully, Photoshop allowed me to collect those remaining residual dust rings (fortunately, only two).

This is 36h 30m of RGB data. For more technical details, see astrobin.