Starry Golden Gate

After photographing the setting Milky Way a few hours north of San Francisco and nearly getting eaten alive by millions of mosquitoes, I skipped camping and headed back to photograph Comet Tsuchinshan over the Golden Gate Bridge.

 

Since I had to escape so quickly, I arrived early, hoping to get some rest in my car. Unfortunately, some bugs had ridden along, so I decided to hike to the overlook and spend the extra time in clear air.

 

As I was enjoying the view, I noticed Orion rising and thought about how cool it would be to capture a nightscape with the winter Milky Way rising over this iconic scene.

 

Of course, that's not possible from such a light-polluted location. Or is it? Well, since I was here, why not give it a try...

 

I took a few test shots, and as expected, light pollution was heavy, requiring much lower exposures than I'm used to. On the other hand, there was still a hint of Ha signal in the narrowband shots, so I took a vertical panorama to see what I could squeeze out of the data.

 

With lots of strong gradients and only weak signal, processing the sky was a nightmare, and it was also a challenge to blend the foreground with the sky, but I find the result quite remarkable.

 

Considering this is a Bortle 5 viewpoint facing Bortle 8 Downtown San Francisco, I find it extremely impressive what can be captured with a modern camera, narrowband filters, and specialized astro processing software.

 

EXIF

Canon EOS-R, astro-modified by EOS 4Astro

Sigma 28mm, f/1.4 ART

IDAS NBZ filter

iOptron SkyTracker Pro

 

All the data captured back to back from the same tripod position:

 

Sky:

Panorama of 4 panels, each a stack of 10x 45s @ ISO800, f/2.8, unfiltered & 5x 105s @ ISO1600, f/2, filtered

 

Foreground:

Manual HDR from 4 stacks, 5x 30s, 15s, 10s & 5s @ ISO800

 

Done