Astrophotography

The Wizard!

October 31, 2024Richard WrightAstrophotography

Happy Halloween! It seems an appropriate day for my latest work, NGC 7380, also well known as The Wizard Nebula. I’ve always loved this nebula as I have an affinity for Wizards and fantasy literature and movies. This emission nebula is colored by glowing hydrogen and oxygen gases. It’s about 8 hours of exposure with RGB filters, and some “narrowband” filters that only let wavelengths of light through from Hydrogen and Oxygen atoms.

So do you see the Wizard? Upper left is his pointed hat. Following the arc down, you see the hands spread out, over a bubbling caldron. Takes a little imagination, but once you see it, you’ll never forget it! I even think I see a little face near the big “bubble” feature under the hat.

Red nebula in space
The Wizard Nebula, or NGC 7380
Red nebula
This is a new feature I’ve not seen before

There is a little something “spooky” going on with this image. There’s a little loop above the Wizards right hand. Small at the end of an area of gas with a glowing edge.

Red Nebula
Close look at this bright loop feature

The loop is very bright, and doesn’t show up in my Ha or OIII images, but it’s very bright in the RGB images.  There’s a bit of a bubble feature here in some images I’ve found, and at first I thought perhaps it was a processing artifact. I went back to the original sub exposures, and it’s very clear, especially in the strong red and green color channels (you can see it in blue too, but blue is usually a lot fainter).

I’ve searched online and sent this to another atro-imaging friend. Honestly, if it weren’t Halloween, I might even have waited to publish this, because I really want to convince myself it’s a processing artifact. I shot the RGB data on October 25th, if anyone out there shoots the Wizard, I’d love to know if you see this too. Or… maybe… it’s a GHOST and it’ll be gone! Muhahahah…

Oh, almost forgot the tech details. This was taken with a Sky-Watcher Esprit 150 and their 0.77x reducer. Player One Poseidon-M camera with Chroma RGB and narrowband filters. Ha and OIII, both 3nm band pass. 8.7 hours total exposure time over three different nights.

I love the expression “Happy Holidays” because there’s a whole bunch of Holidays and they start with Halloween for me. So, let me be the first to say Happy Hallowe…. Holidays!

 

An Old School Galaxy

October 27, 2024Richard WrightAstrophotography

Astrophotography did not start in color. Various chemical techniques culminated in using glass plates with chemical films, which still produced a black and white image. A technique still in use at professional observatories in the 1970’s when the original Star Wars was released. My most unpopular advice about astrophotography today is to start with monochrome sensors and do monochrome imaging. Monochrome (black and white) sensors are far more sensitive than color sensors. Yes, CMOS is great kiddies, but CMOS mono is still even better than CMOS color! An ongoing project of mine is “Backyard Galaxies”, where I shoot galaxies from my light polluted back yard outside Orlando Florida. I use a monochrome sensor, with no light pollution filter. Color is very hard to do in light polluted skies, but I find monochrome works quite well. Yes, you have to take short exposures so as not to saturate your sensor, and the raw image is awash with light. Curves and levels however will bring that image right out. I might have to do a longer piece on why this works sometime, but for now, I encourage you to give it a try. The image below is only 38×90 second exposures. I used a Sky-Watcher Esprit 150 refractor with the 0.77x focal reducer and a Player One Poseidon M camera and a Chroma Luminance Filter (necessary even for monochrome images).

Black and white galaxy image
The Triangulum Galaxy (M33) in monochrome.

Oh, this by the way is Messier 33, the Triangulum galaxy. It’s a fairly large galaxy in apparent size as it’s not terribly far away. Only 2.7 million light years!

What are you waiting for? Got get yourself some backyard galaxies for too!

A narrowband Moon

September 30, 2024Richard WrightAstrophotography, Lunar Observing and Imaging

Deep sky astrophotographers often resort to a “narrowband” filter (or line filter) to image deep sky objects when the Moon is up. This is because Moonlight scattered in the sky often washes out most color filters. However, when imaging emission nebula, we often will use a special filter that is sensitive only to a particular wavelength of light that is emitted by these narrowband targets. The most common is called “Hydrogen Alpha”, and it gives many nebula a bright pink/red appearance when photographed. This wavelength is not scattered in the sky by Moonlight and so you can do perfectly good “deep sky imaging” when the Moon is out. In fact, this particular wavelength is also great for light polluted areas.

I love the Moon too though, and every time I find myself using one of these filters because the Moon is up, I also turn the camera towards the Moon for a shot. These kinds of filters produce a monochrome image, but that’s fine for the Moon. In addition, they are very much in the red end of the spectrum and these wavelengths are slightly less perturbed by a turbulent atmosphere, which can result in a sharper image.

Big Gibbous Moon

Deep sky astrophotographers often resort to a “narrowband” filter (or line filter) to image deep sky objects when the Moon is up. This is because Moonlight scattered in the sky often washes out most color filters. However, when imaging emission nebula, we often will use a special filter that is sensitive only to a particular wavelength of light that is emitted by these narrowband targets. The most common is called “Hydrogen Alpha”, and it gives many nebula a bright pink/red appearance when photographed. This wavelength is not scattered in the sky by Moonlight and so you can do perfectly good “deep sky imaging” when the Moon is out. In fact, this particular wavelength is also great for light polluted areas.

I love the Moon too though, and every time I find myself using one of these filters because the Moon is up, I also turn the camera towards the Moon for a shot. These kinds of filters produce a monochrome image, but that’s fine for the Moon. In addition, they are very much in the red end of the spectrum and these wavelengths are slightly less perturbed by a turbulent atmosphere, which can result in a sharper image.

Deep sky astrophotographers often resort to a “narrowband” filter (or line filter) to image deep sky objects when the Moon is up. This is because Moonlight scattered in the sky often washes out most color filters. However, when imaging emission nebula, we often will use a special filter that is sensitive only to a particular wavelength of light that is emitted by these narrowband targets. The most common is called “Hydrogen Alpha”, and it gives many nebula a bright pink/red appearance when photographed. This wavelength is not scattered in the sky by Moonlight and so you can do perfectly good “deep sky imaging” when the Moon is out. In fact, this particular wavelength is also great for light polluted areas.

I love the Moon too though, and every time I find myself using one of these filters because the Moon is up, I also turn the camera towards the Moon for a shot. These kinds of filters produce a monochrome image, but that’s fine for the Moon. In addition, they are very much in the red end of the spectrum and these wavelengths are slightly less perturbed by a turbulent atmosphere, which can result in a sharper image.

The “Seeing” (amount of turbulence) was very good this evening (very still air), and I rather think I got an exceptionally sharp image of the Moon here. The only processing I did of this image off the camera was curves for tonal adjustments. I did no sharpening at all. The optic was a Sky-Watcher USA Esprit 150 with their 0.77 reducer. This is one of my top scopes and on this evening it did some of it’s best work under exceptionally good skies. The camera was a monochrome Player One Poseidon-M, and the filter was a Chroma 3nm Ha filter. The exposure time was 0.1 second.

Yes, I have some deep sky images from this evening too, but I’m still collecting light for those images before they are finalized.

 

 

Annies Dragon

September 28, 2024Richard WrightAstrophotography

A well known and often shot emission nebula in the constellation Cepheus is the “Elephant Trunk”. Cropped in on just the trunk people see all sorts of things. One day by chance my wife saw the image rotated in a such a way, that she said it looked like “Smaug the dragon” (from the Hobbit). I thought, it REALLY DOES. So, at least to me for now on, this object is forever more “Annies Dragon” (my wife’s name is LeeAnne).

Dragon shaped nebula
Annies Dragon is an emission nebula that is a part of IC 1396.

This particular image was just shy of two hours of hydrogen alpha exposures with a Player One Poseidon-M camera and Chroma 3nm Ha filters. Normally, these monochrome Ha images are grayscale but I did add just a tint of redish brownish to give it a sepia-tone type treatment. It’s a photo of a dragon after all, and one day it will be an old photo of a dragon 😉

 

Solar Nirvana?

July 28, 2024Richard WrightAstrophotography, Solar Imaging

The weather for astrophotography in Florida is so dismal in the summer, or rainy season as I call it. Even when it’s bright and hot outside, there’s a haze of moisture and thin clouds most days, and the nights are quite opaque. We had a break the other morning and I had a chance to get out some new gear I’ve been curating. I think my solar rig is “almost” as good as I can hope for, and I captured a nice view of the Sun the other morning (7/26/2024) and Active Region 3762.

The Sun in Hydrogen Alpha light and my rig used to capture it.

I have a DayStar Quantum 0.5 Angstrom Ha filter. This is a very specialized filter for capturing light just from glowing Hydrogen in the Sun’s atmosphere. It reveals an amazing amount of surface details, and it works on the back of most any refractor as long as it isn’t too big. I will be honest, it’s an advanced piece of astro-gear, and I struggled a bit to get the tip top performance out of it for a while. Focal ratio matters, sort of. What really matters is nice parallel rays of light coming into it, and certain optics technically change the focal ratio, but don’t necessarily produce the most parallels rays. I also have found, despite my earlier confidence, that a front mounted energy rejection filter helps a great deal (ERF). I bought an 82mm Lunt ERF second hand in a custom 3D printed cell that fits my Astrophysics Stowaway telescope. I use a TeleVue Powermate or a Baader 4X Telecentric on the back to get the focal ratio/parallel light rays going.

Other luxuries in this photo. A Paramount MYT with absolute encoders, which is an absolute joy to use. Already aligned and ready to go, you just flip a switch and go. The scope is an Astro-Physics Stowaway refractor, there’s a waiting list and/or lottery to get  these fine refractors. I really think Roland Christen is the modern Alvan Clark. There’s a top of the line Feather Touch focuser on the back, and an Optec QuickSync motor on it. Finally, a Player One Apollo Max on the back is taking the images. One further improvement is a cooled camera. There’s some debate as to if this really helps with solar imaging, but I do find that the fact that the temperature is regulated does make a big deal. Not so much that it’s “reducing noise” in the raw images, but calibration frames need to be at the same temperature if you you want the flat frames to work properly. Nine times out of ten, it doesn’t seem to matter, but occasionally, I’ll end up with flats that won’t work, and this is the reason why. Some helpful advice… “Just keep your optics clean”… makes me laugh.

I think this is just about as good as it gets for a high quality solar rig for myself. I might have to get a 3D printed cell for that ERF to fit my Esprit 150 though. It’s only taken some 30+ years of wheeling and trading up to get here. As Ferris Beuler says, “If you have the means“… maybe you won’t have to wait 30 years 😉

Now… how about some clear skies?

 

Montes Apenninus

May 18, 2024Richard WrightAstrophotography, Lunar Observing and Imaging
The Apennes Mountains on the Moon
Montes Apennius bisects Mare Imbrium and Serenitatus

As a child, my family would visit the Great Smoky Mountains in Tennessee, often multiple times a year. I imagine future lunar citizens might vacation in the Apenninus mountains, a beautiful chain of mountains that curves along the edge of Mare Imbrium on the left side of this image. Named after a mountain range in Italy, it has a small gap (perhaps analogous to the Cumberland gap of my childhood home) that opens the way from Imbrium to the sea of Serenity to the right. Were the lunar maria actual oceans, there would for sure be a vibrant trading city located here as the most practical passage between these two great seas.

Alas, this is the Moon, and the Maria are indeed not waterways, but vast plains of cooled lava… well… a sea of frozen lava is still a sea, isn’t it?

Taken on the night of May 16, 2024, the lighting here is really quite outstanding for great views of a number of prominent features in this area of the Moon. At the upper left we see the crater Plato, which often looks quite shallow and flat. Due to the Sun’s angle at this time however you can see the highly detailed walls of the crater rising high above the smooth surface of Mare Imbrium. To the upper left of Plato, you can see a small ring of light that is the crater Fontenelle. Through the eyepiece this night, that ring was glowing in the darkness of the terminator like the lights of a great city in the night.

Midway down and to the left of the Apenninus mountains is another flat and smooth crater Aristarchus. Like Plato this crater appears to be older than the Mare Imbrium as its floor is flooded with the same cooled lava that surrounds it. A younger crater at the southern tip of the mountain range is Eratosthenes. There is no smooth floor here, and in the center, you can see a tiny dot of light that is the central peak of a mountain of material that was rebounded when the impact crater was formed.

While the Moon is not quite as dynamic as the Sun, it is different every night, and even every hour you can see changes in the surface as the light and shadows dance across the lunar day. Even the smallest telescope or binoculars will reveal this world to you, and I encourage you to go take a look as often as you can.

Just One Hour

May 5, 2024Richard WrightAstrophotography, Basic Photography

The August, 2024 issue of Sky & Telescope has an article by me about shooting star trail images. It’s too bad I didn’t have this shot before because it’s my favorite star trails image to date. I setup my camera behind an equatorial mount (I was shooting M106 at the time), and set my canon EOS Ra to take 30 second exposures repeatedly. Then, as I describe in my afore mentioned article, I loaded all the images as layers in Photoshop and set the blend mode to “Lighten”. I did paint out a few airplane trails in the individual layers, but otherwise the image is accurate. There are even a few short meteor bursts if you look carefully for them.

Star trails over a telescope
One hours worth of star trails show just how much the stars appear to move in such a short amount of time.

This image shows why we use an equatorial mount for long exposure astrophotography. As the Earth spins, the stars move considerably, and in this case you can see exactly how much in only an hours time. An equatorial mount works by aligning it’s axis of rotation with the Earth’s, and then rotating in the opposite direction of the Earth’s motion. It’s like being on a merry-go-round, and you have to turn your head to keep looking at someone or something off in the distance. Without an equatorial mount, objects zip by in the eyepiece or camera pretty quickly. There are also alt-az mounts that track objects in the sky without having to do much alignment work, however, because of the way they move, objects in the camera will rotate in place as you track them across the sky. This makes long exposures a bit more challenging 😉

For context, I’ve added just a single 30 second frame as well. As a stand alone image, it’s not too bad either IMHO.

Richard

A telescope against a starry sky
Here’s just one of the 120 frames used to create the star trails image.

Totality at Last!

April 23, 2024Richard WrightAstrophotography, Eclipses

Total Eclipse SequenceYou’d think given my years of astrophotography (if not just my age!) that by now I’d have seen a total eclipse. The total eclipse of April 2024 that crossed North America was not my first attempt at a total eclipse, but it was my first successful attempt at witnessing a total eclipse! I can now tell you; the hype is real.

The Diamond Ring Effect
The Diamond Ring at the beginning of totality during the 2024 total solar eclipse.

I went to the Texas Star Party, which was moved both in location and time to coincide with totality and we were nearly right on the center line for nearly four and a half minutes of totality. That was the fastest four and a half minutes of my life. I can now understand why people tell you that you should not “focus” on astrophotography at your first totality. Of course, that advice is lost on me (and probably some of you) because photography is in our DNA. I did not however completely ignore the advice. My photography rig was 99% automated. All I had to do was remove the front white light filter at totality and put it back on after totality.

My gear choice was pretty much ideal. I used an equatorial mount to keep the Sun’s orientation constant throughout the eclipse (Sky-Watcher Az-EQ6 in EQ mode). I polar aligned it on a previous evening using the integrated polar scope. For optics, I used an Astrophysics Stowaway 92mm refractor with the f/7 flattener. I had made a front mounted white light solar filter from Baader solar film for the 2017 eclipse that I reused this year. I

Total Eclipse
The Sun and Moon during totality. Note that bright prominence at the bottom just peeking through low areas on the lunar limb.

removed it during totality, and thus got nice safe images of the partial phases, and when it was safe (for the camera) I got Baileys Beads, the Diamond Ring, and some great prominence and corona images during totality. The camera was a Canon EOS Ra mirrorless full frame camera. The “a” means astronomical as it is slightly more sensitive to the hydrogen alpha wavelengths of emission nebula… and as it turns out, solar prominences!

Finally, the software the drove the sequence on my MacBook Pro was “Capture Eclipse”, which is a great program I can’t recommend enough. I rehearsed at home of course, and I focused using the @focus3 algorithm in TheSkyX Professional (which I wrote btw) on the sunspots right before the eclipse started. The telescope was already at equilibrium, so there was no focus drift during the eclipse.

Prominences on East side
Prominence’s on the Eastern limb of the Sun. Note the rather large triangular prominence at the bottom. This was visible to the naked eye during the eclipse.

I must say, I really lucked out. Sure being prepared helps, trying repeatedly helps, but the weather forecast shifted from seasonal norms to mostly cloudy for eclipse day. We got fortunate that the clouds parted for us and although we had a few thin clouds and the occasional thick cloud, we were rewarded with a glorious view of totality. While I’m very pleased with my images, there is absolutely no comparison to the view naked eye. If you can possibly make it to center line for a total eclipse, I highly recommend you make the effort. I know my passport will be ready for some future eclipses…

Additional and larger versions of these photos are available in the Sun gallery. My favorite shot of Baileys Beads is below!

 

Baileys Beads just before totality ends. These are caused by sunlight filtering through gaps in the lunar terrain like mountains, valleys, and craters.

A Tale of Two Filters

March 2, 2024Richard WrightAstrophotography, Solar Imaging

Like a lot of photographers in North America, I’ve been making preparations for the total eclipse coming up in slightly over a month now from the time of this writing. I’m planning to take an arsenal of solar gear and spend a couple of days doing solar imaging with a variety of gear and techniques, and fleshing out some software I’m working on for lucky imaging to boot. This means I’ve been doing a lot of solar viewing and imaging in my back yard, and cycling through gear to make sure I have all the right adapters, spacing, etc. There was a very active region on the Sun (AR 3590) on the clear afternoon of February 27th and I had a chance to image it in white light and then just a few minutes later in Hydrogen Alpha. The difference is quite stark and I thought very illustrative.

Two images of AR 3590
Active Region 3590 in Ha and white light.

The telescope was a Sky-Watcher Esprit 150 (still my favorite optic for just about anything), which I had on my Paramount MX+. The Paramount’s have the smoothest motion of any mount I’ve ever used for any kind of high resolution Solar or Lunar work, but back to topic. The top panel at right was taken with a 4x Powermate to get the image scale and focal ratio higher for the Daystar Quantum hydrogen alpha filter. I used a Player One ERF (Energy Rejection Filter) in front of the PowerMate. I don’t use a big ERF in front of the 6″ objective, but 6″ is about as large a refractor as anyone should dare use for solar without a larger ERF in front of the aperture. The camera on the back was Player One Apollo Max, and I shot about 5,000 frames, of which I used 20% for the final stack. The original image was monochrome, but I colorized it as most people (my wife especially) prefer to see a nice color image. The mad truth is the single wavelength of Ha is an electric pink, but the convention is to make these images yellow to conform with the public’s perception of what color the Sun should be.

Ha images are stunning. They show in stark relief how the gasses are flowing along magnetic field lines on the Sun’s surface. The darker areas are still quite hot and blindingly bright, but they are just ever so cooler than the surrounding areas, and the white areas are as you’d expect super hot and bright.

The bottom image was taken with a Starfield Herschel Wedge. A Herschel Wedge is a lot like a normal star diagonal you see on many telescopes, but it let’s the majority of the Sun’s light pass through it out the back. A tiny portion is reflected up towards an eyepiece or camera for viewing. It simply dims the Sun, so you see the Sun as it actually appears, just a lot less bright and hot. Not using a filter like this would blind you instantly, or melt your poor camera before you could hope to get a shot off.

I still used a 4x PowerMate and the monochrome Player One camera, but replaced the Player One ERF (which is tuned for Ha imaging) with a standard UV/IR filter. The Herschel Wedge does not need this normally for visual work, but when doing photography, it eliminates some of the stray light that would be out of focus. The result is a “White Light” image of the same region. You can still see some of the same overall structure of the region, but you are not seeing the effects of the magnetic field lines that are more pronounced in the hydrogen bandpass.

The true color of the bottom image is actually… white. The Sun appears white in space, and even on Earth when directly overhead. It’s hard to tell of course because well, looking at it long enough to study it’s color would of course blind you! Still, I chose to colorize it for aesthetic purposes to match the image above. Scientifically, the images represent the structures accurately (even the limb darkening at upper left is real), but the colors are for taste alone.

I hope you can forgive my creative license (or shameless conformity), and enjoy seeing the difference between these two common ways to filter and view or photograph the Sun.

Bernard’s Merope Nebula

January 1, 2024Richard WrightAstrophotography
Merope Nebula image
Bernard’s Merope Nebula

This was a challenge target for me. Last month I was writing my monthly astrophotography target of the month column for Sky Safari (you will need a subscription to see it in Sky Safari Pro), I realized I did not actually have a good image of the Pleiades that featured this tiny jewel (cataloged as IC 349). I love to shoot the larger reflection nebula with a newtonian reflector because it makes beautiful diffraction spikes, but the spikes would obliterate this tiny little interloper to M45. Same with other refractors (or my Officina Stellare RH-200) I had used with longer exposures – the star Merope would swell up and swallow this nearby nebula, which physically is only 0.06 light years from the star!!

The Pleiades are a relatively bright group of stars and nebulosity, so I went for a short run under somewhat light polluted skies. I used 111 good 30 second exposures stacked for this image, and stretched VERY gently with the histogram and curves tools. The seeing was not super great that night with my Espirt 150 refractor and a Player One Ares-C Pro cooled color camera, so I confess as well I used the very nice Blur Exterminator to tighten the stars a little bit.

An interesting personal experience about this image. This is the first time since I’ve started wearing glasses (none of us are getting younger!), and just like a star test is a good way to test optical flatness, I found that when judging my star field on the computer screen, I could see… and DISTRACTINGLY SO… distortions in the star field that aren’t actually there. This can make it very hard to judge an astro image, and I now have TWO pairs of glasses. One for “most of the time”, and one for when I’m using my computer or working… um… well, truthfully that IS most of the time – LOL.

P.S. Happy New Year and Clear Skies!