Greg Marshall


About Greg Marshall

I am a retired electronics engineer and after a few months of enjoying my leisure I began to miss doing product development. My astronomy hobby always needed new solutions to unique problems, so I decided that whenever I came up with a good solution I would try to make it available to others.


Feeling Blue?

The last of my images from OSP is NGC6914, a small reflection nebula in Cygnus.  To be honest, this includes a lot of data captured from home in addition to what I captured at OSP.  Specifically, the majority of the image (the red areas) are hydrogen, and knowing that I could get that with a narrowband H-alpha filter from home, I didn’t shoot with that filter at OSP. But combining the RGB and H-alpha data did not work out the way that I had hoped.  If there were no stars in the image it would be a simple matter of […]


A Pinwheel in the Northern Sky

Here’s another image from the 2019 Oregon Star Party, M101, the Pinwheel Galaxy.  Also cataloged as NGC5457, the Pinwheel is a large galaxy in Ursa Major, and about 21 million light-years from Earth.  Although not as large in diameter as our Milky Way (170,000 light-years versus 258,000 light-years), M101 has about 1 trillion stars, twice as many as the Milky Way.  It also has a lot of hydrogen regions that are typically star-forming regions. As with most of my broadband (natural color) images, this was captured and processed using LRGB, with only a handful of color frames (8 each of […]


Another Wild Flower from OSP

It seems that every year when I go to OSP (Oregon Star Party) I end up shooting this beauty, the Iris Nebula, and each year it gets a little better.  I had not planned to shoot it again this year, but when I saw how good the seeing was on the second night, I just had to drop what I was doing and move on to the Iris. The Iris (NGC7023) is a reflection nebula in the constellation Cepheus, which has many great targets for astrophotography.  As with the Pleiades cluster, the blue appearance is really just the color of […]


Off to OSP

I’m packing up my gear to go to the 2019 Oregon Star Party.  OSP has always been held near the New Moon period in August, but this year we have 2 New Moons in August.  Since there has been some pressure to move the star party to earlier in the Summer, I guess it was pretty easy to choose for this year.  The reason for the pressure to move is that in recent years the event has been marred by smoke from wildfires, and there is a lower risk of fires earlier in the Summer.  But earlier also means a […]


The Cocoon Nebula

The other target I captured at the Golden State Star Party is the Cocoon Nebula (IC5146), which is, coincidentally, somewhat similar to the Trifid Nebula in appearance and structure.  The red portion is emission nebula, but the faint blue and brown regions are reflection nebula.  The Cocoon is in the constellation Cygnus, so much higher in the sky than Trifid.  Although it was nice to be able to photograph objects farther south, I wanted to get at least 1 target that was not so close to the horizon and the blurring that happens down there.  There was still a fair […]


The Trifid Nebula from GSSP

One advantage to making the long trip to GSSP is that it is more than 5 degrees south of home, so objects in the southern sky are more than 5 degrees higher above the horizon.  I had intended to photograph a new (to me) target, the Blue Horsehead Nebula, but found it to be too big for my gear – I could fit only a small portion of it in my field of view.  So instead, I went back to a familiar target that I hadn’t photographed for years, the Trifid Nebula. Also known as Messier 20, Trifid is partially […]


Golden State Star Party

Just back from GSSP, the Golden State Star Party, near Adin, CA.  Above is a photo of my astrophotography rig, with my motorhome behind it, and the Andromeda Galaxy in the lower left (WAY behind it).  It was a 450 mile drive, and its always questionable whether a star party is worth such a long drive, but we did have a good time. In comparison to the Oregon Star Party (OSP), GSSP is a little smaller, with about 400 attendees.  The location is attractive, and doesn’t have nearly as much dust as OSP.  It is on farm land that is […]


Welcome to Summer!

Today (June 21st) is the Summer solstice, so it is now officially Summer.  And the longest day/shortest night of the year. I think that amateur astronomers have mixed feelings about Summer.  It’s annoying that the night is so short (tonight, even without the Moon, it would be truly dark for only a few hours), and you have to stay up pretty late before it starts.  On the other hand, you can stay up through all of it and still get to bed long before it’s time for breakfast.  And usually, you can stay up all night without freezing. I must […]


A Home Galaxy

It’s fun to imagine that distant worlds might be home to other sentient beings, who stare up at their night sky to see the Milky Way Galaxy (although, even translated to their language, that would be a very odd name for it).  Perhaps there is some such world or worlds in the Whirlpool Galaxy, also known as M51 or NGC5194.  But in this case, “home galaxy” means that I captured this image of M51 from my home observatory, which is unusual because 99% of the images I capture from here are narrowband images of emission nebulae.  And I was surprised […]


Another Image from Last Week

You might notice that both this and my previous post have images of galaxies rather than my usual nebulae (and more specifically, emission nebulae captured with narrowband filters).  That’s partly because I wanted to take advantage of the dark sky at the star party to photograph things I can’t shoot from home.  But it’s also true that at this time of year, the Milky Way doesn’t come up until 3AM or so, and all of the nebulae we photograph are in the Milky Way, so it’s now “galaxy season”. The largest galaxy in this image is M106, also known as […]