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.

Still Here

It has been over a month since I last posted here, and I don’t have any new photos to share with you – sorry!  It’s not because the coronavirus has slowed me down.  I’ve been staying home almost entirely, and as far as I can tell, am still healthy.  Some people have actually had more time available for hobbies since the virus has caused closures and lock-downs all over the world.  And all too many people no longer have jobs to go to.  In my case, I have been very busy developing some new products, and would have had pretty […]

The Last of California

No, California isn’t going away, this is just the last photo from my recent trip down there.  This is M78, captured with the SVX80T at f/6, and the ASI1600 camera.  I shot the same target last year with the WO Star71, which has a significantly wider field of view, and also got it from the remote observatory in Australia with a somewhat narrower field of view.  I’ve repeated the effort because none of these captures has been entirely satisfactory.  This one is better than I expected given that it was captured in just 6 hours or so, over the last […]

What’s Up with Betelgeuse?

Today’s APOD image is fascinating on several levels.  The pair of images above are of the star Betelgeuse, a “red supergiant” (type M1-2); one at the beginning of 2019 and the other at the end of the year.  Aside from our own Sun, we generally think of stars as true “point sources” of light, having no dimension.  Even though Betelgeuse is an enormous star (if it were located where our Sun is its outer surface would be out past Jupiter), and relatively close at about 700 light-years, it is quite remarkable that our modern telescopes are able to actually resolve […]

Easy Hard

Here’s one more image captured during my trip to California, the Orion Nebula.  Orion is a favorite of both astrophotographers and visual observers.  It is often the first target beginners shoot, and one that some people shoot over and over again.  In fat, the first astrophoto I captured that I was really happy with was of the Orion Nebula.  Part of the reason for its popularity is simply that it is gorgeous.  But equally important for the beginner is that it is very bright, so it’s relatively easy to get a decent image of it. At the same time, it […]

A Horsehead from a Horse Country

I’m back home from California, and starting to work on some of the images I captured down there and haven’t yet processed.  The place we set up our telescopes is actually right next to where some horses live, so it seemed appropriate to shoot the Horsehead Nebula in Orion.  Well, I was planning to shoot this anyway, but I hope all the horse people out there will appreciate it. The Horsehead itself (below and slightly right of center) is a dark nebula, a dense cloud of dust that is blocking light that originates behind it, forming a silhouette.  In many […]

Last Days

This “young” crescent Moon was captured on 1/26 from the parking lot of our condo.  At that time it was thin enough and set early enough that it had no impact on astrophotography, but in a few days it will become annoyingly bright and late.  Accordingly, we’ll be returning home soon, although I am not looking forward to the gloomy weather that will plague the Portland area for months to come. I have captured some other targets that aren’t yet processed, and probably won’t be until after we get back home. It was a great trip.  Aside from some very […]

Updating an Old Favorite

Back when I was selling prints of my astrophotos, the Pleiades/Subaru image was my best seller, even though it was done long ago – when my skills were significantly less developed.  And since it is well positioned in the sky now, I decided to shoot it again and use more sophisticated processing. The problem with the original version is that the very bright stars are “blown out” – just large white blobs.  Getting them to look more like pinpoint stars requires shooting some much shorter exposures in addition to the long exposures needed to get the faint dust.  The trick […]

IC410 Tadpoles

My last astrophoto was of IC405, also known as the Flaming Star Nebula.  IC410 is a close neighbor of IC405 – a bit of it is showing at the edge of the IC405 photo.  This nebula is best known for a small feature near the center, known as “The Tadpoles”: Most of the data for this image was captured near the full moon, and even though it is all narrowband data (using 3nm filters), the moonlight and haze made the O-III frames pretty bad.  The S-II frames were also less than ideal, so I leaned heavily on the H-a data […]

Moonrise Over Font’s Point

Yesterday’s Full Moon seriously limited the amount of deep-space imaging I’ve been able to do lately, but also provided a great opportunity for some “terrestrial” photography.  My friend, Mike, had calculated where we needed to be to place the rising moon just over Font’s Point, a popular local attraction.  I wasn’t really prepared for this in that I didn’t have a long focal length lens and hadn’t worked out how to bracket the exposures to capture both the dimly lit foreground and the very bright moon.  This was captured with a 200mm lens on a Nikon D300 camera.  I could […]

Flaming Star from California

My second image from our Winter in southern California is the Flaming Star Nebula (cataloged as IC405, Caldwell 31, and Sh2-229).  This was captured with the new Stellarvue SVX80T with 0.74X reducer/flattener, yielding an effective focal length of about 350mm at f/4.4.  With such fast optics a lot of information can be captured in a relatively short time.  In this case, I captured 4 hours of H-alpha, and 2 hours each of O-III and S-II.  The downside is that the optics are very sensitive to spacing and tilt.  Stellarvue recommends a spacing of 55mm +/-0.75mm from the reducer to the […]