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.


I Couldn’t Resist

I’m very busy and more than a little sleep deprived, but I have to share this with you:  I knew when I saw the first Hydrogen-alpha frame that this was going to be an interesting image, so after completing the capture Tuesday night, I processed it – and was even more pleased with the final image than expected. The object is another from the Sharpless catalog, Sh2-132.  Like many of the objects in the Sharpless catalog, it doesn’t have a common name, but I’m going to call it “The Ghost Rider Nebula”.  Do you see it?  The large arc in […]


Busy Days and Dreary Nights

The night sky has actually been completely free of clouds for several days.  Unfortunately, it has not been free of smoke.  Only a few of the brightest stars can be seen and the Moon looks decidedly yellow.  And the same weather pattern that is allowing this smoke to stick around is also keeping us very warm here.  Daytime temperatures have been well over 100 degrees F, and at night it doesn’t get cold enough for my camera to operate properly, so it’s a double whammy. I’m getting ready for the Oregon Star Party – and the eclipse!  My inventory has […]


Table Mountain Star Party – Trip Report

It has taken a few days to recover from the long drive back from Eden Valley (just east of Oroville, WA) and the Table Mountain Star Party.  I had never been to this event before, although it has been going on for longer than I’ve been into astronomy, and it used to be much closer.  So while I don’t yet have any astro-photos from there, I want to give you a quick report. To put it in as few words as possible:  Wonderful!  Aside from the long drive, that is.  Not so many years ago, this star party was held, […]


Sharpless 86 in Vulpecula

I did it again.  Here is another object from the Sharpless catalog, taken over the last few nights.  Capturing this has, unfortunately, kept me from processing the images I took at the last star party.  Not so much because I haven’t had time, but because I need to capture some calibration frames (what are called “flat frames”) before I can process them, and that means switching the camera from narrowband filters (what I use in my home observatory) to the RGB filters I used at the star party, then back again.  But I will get to them eventually. Sharpless 86 (Sh2-86) […]


A Sharp Picture of a Sharpless Object

A while ago, I posted a monochrome image (H-alpha channel) of M16 and another bright, but unknown (to me) hydrogen region.  The second object did not appear in my planetarium software and very few images I could find on the internet included it, so I asked people for help in identifying it.  I eventually came up with an answer myself:  It was Sh2-54, AKA Sharpless 54.  More importantly, this led me to the online catalog of Sharpless objects, http://www.sharplesscatalog.com/. Stewart Sharpless was an American astronomer who worked on a number of important projects and with some well known astronomers, including Edwin […]


Star Party in the Round

Recently, a friend has been making 360 degree by 180 degree panoramas of the night sky in various locations as part of a light pollution study.  As you can see, this is a pretty useful tool to document and demonstrate what light pollution looks like, but it also makes a pretty nice picture, so I asked him how to do it.  Mike was very helpful.  Not only did he show me how to do it, he loaned me his fancy tripod head to capture the frames, and did part of the processing that requires some software I don’t have (yet). […]


Pioneer Days

Things are crazy busy here at Wa-chur-ed Observatory, but I wanted to take a minute to tell you about the event we did last weekend, the Linn County Pioneer Picnic in Brownsville, OR.  This was a 3 day event filled with all manner of family fun.  We were located at the end of the vendor area, next to a rock climbing wall provided by the OR National Guard.  That drew a lot of people to the area, but was also a distraction.  In any case, it was great fun to watch kids climb the wall – especially the little ones, […]


The Eagle and the Unnamed

M16, the Eagle Nebula, is a beautiful and often photographed object in the southern sky (when viewed from the northern hemisphere).  It is the northern-most of a series of well known objects in the area, including M17, M18, M20, and M8.  But in this photo M16 is in the lower right corner and the object in the upper left is farther north.  What’s interesting about this is that although the object in the upper left is quite bright (and although smaller than M16, not particularly small compared to typical astronomical targets), it has no common name.  In fact, so far […]


To Capture a Globular Cluster

I’ve tried many times to get a good photo of M13, the Hercules Cluster, and this is the best one yet, although it’s done with a telescope that is a bit low in magnification for this object.  M13 is a “globular cluster”, a group of stars that are gravitationally bound to each other.  In this case, there are about 300,000 stars in the cluster, so the goal in photographing it is to be able to distinguish one star from another as much as possible (obviously, we can’t come close to seeing all 300,000), which means getting excellent sharpness. Theoretically, a […]


Astronomy Season has (Finally) Arrived

Over the past week we’ve had some really great weather here in the Pacific Northwest, and I took advantage of the clear skies to start the astronomy season – with astro-photography, of course.  There are some dark-sky star parties going on as a write this, and I didn’t go because there is too much work to do at home, but that didn’t keep me from opening up the observatory and starting some semi-automated captures. The target this time was NGC6888, the Crescent Nebula.  This is a popular target in the Cygnus constellation, and is often photographed, both in natural color […]