astrophotography - Brian Fontenot, Author

January 1, 2021January 2, 2021

DSLR Astrophotography – The Journey

For the longest time, I relied on my smartphone and a telescope to take pictures of planets and bright nebula. I got pretty darn good at it, too. But learning to use my “old” Nikon D5300 to take pictures through my telescope has really begun to pay dividends.

I purchased my camera not long after I received my 6 inch Celestron PowerSeeker 127EQ scope for Christmas. After attaching my new camera, which I got as a really good Best Buy Outlet refurbished deal, I was quickly discouraged by the image quality. As new to the game as I was, I believed that I could merely connect my camera to the focuser of my scope with a bulky T ring adapter and get better results than my trusty smart phone. I was wrong, obviously. First, I had to disassemble the focuser on that particular scope to remove the corrector lens, which left me unable to use to scope for anything else until I reinstalled the lens. Once I got the camera connected in a state where it could even be focused, I lost so much image magnification compared to my phone and found it nearly impossible to focus cleanly.

I felt like I had wasted $300. I tried some daytime photography of flowers and other things, but I felt like I was getting better pictures from my much cheaper and easier to use Sony Cybershot. So, I shelved the camera for a while until I purchased my first telescope upgrade, my 8 inch Dobsonian, an Orion SkyQuest XT8 and tried again. I had the same issues as before, except now the camera overbalanced the scope, requiring me to drop some more bucks on a half-pound magnetic counterweight. I ended up shelving the camera again.

Early last spring, 2019, a good friend of mine was cleaning out some stuff from his attic and retrieved his old telescope setup. He had purchased it years before, never could figure out how to use it, and just stored it. It included a computerized mount, an Orion Atlas EQ-G, its own 8 inch Dobsonian, and a heavy duty tripod to match.

My Dad had also gifted me an Orion AstroView 90EQ for Christmas. It was the last Christmas gift he would ever get me before he passed on Dec. 30, 2019 from pancreatic cancer. I had hope to use that scope and its steadier equatorial mount to attempt some longer exposures with a battery powered motor driving the mount. I didn’t quite understand, yet, how to get it to work and getting that scope to hold on an image with that setup was a pain, especially with my phone attached.

I ended up combining the AstroView scope with the EQ-G mount. My friend’s Dobsonian was a little banged up and even after cleaning the mirror and collimating it, the image quality wasn’t especially sharp.

And just a quick aside, it took weeks to even get the EQ-G mount working. My friend had misplaced the controller and the AC adapter. A replacement for the controller was somewhere around $200, so I spent a fair bit of time trying to buy the right cable and find the right software to control the mount with my laptop. That ended up being a dead end, so I broke down and purchased the controller.

Before officially going with the AstroView scope, I wanted to learn how to use the mount. I took it out to my local astronomy society’s dark site on top of a levee at the back of a cow pasture. It was an hour drive away and the equipment weighs a ton. The mount alone easily weighs at least 35lbs. The scope was another 30lbs. The counter weights are maybe 15lbs each. And the tripod is maybe 20lbs.

I got it all setup on this levee in the dark and cold, but couldn’t get it polar aligned until a member from the society came over and help me identify the proper star, Polaris, and exposed me to the alignment scope built into the mount with its own special crosshairs for aligning Polaris just slightly off the actual pole of the earth.

After going through multiple iterations of 3-star alignment checks to prep the “Go To” function, I had the heavy Dob and the heavy mount pointed to Orion’s Sword, M42. With my phone attached, I captured my first “long” exposure of the nebula at 10 whole seconds, and was blown away by the color I got.

The months that followed saw me learning to align the mount on my own and attempting to use the 10 seconds of exposure time on my phone to take pictures of the Andromeda Galaxy, Orion’s Sword, and some other deep sky objects (DSOs) that were up in the night sky at the time. I didn’t know I had no chance in hell of getting much of anything back from those with 10 seconds of exposure under a Bortle 7-8ish sky,

I was keenly aware of image stacking and more advanced photo editing options than were available on my phone. I just didn’t have a great way to capture many shots or longer exposures with my phone. That’s when I went back to my Nikon. I reattached it the old Dob, and ran into an immediate problem. It was just too heavy and hard to balance on the end of that Dob. Worse still, was I had virtually the same exposure time limit on the camera as my phone!

Swearing, I started researching how to take longer exposures with a DSLR camera and discovered the existence of intervaluemeters. For $30 I got a little wireless remote control for my camera that let me program multiple shots, up to hundreds if I wanted, for as long as I wanted. It was a game changer for me.

I ditched the old Dob, purchased new rings to be able to attach the AstroView scope to the EQ-G mount and really began my journey with trying to take multiple long exposures of the Whirlpool Galaxy, M51. Andromeda had long since moved on for the year.

I spent night after sweaty, humid night trying and failing to get usable pictures, learning how to point the scope at an object I couldn’t actually see with my eyes, troubleshooting why my images would come out motion-smeared, and beginning to learn how to use Deep Sky Stacker (DSS). And even though I took maybe a few hundred pictures of M51, the results were less than impressive, relative to what even the folks at the local astronomy society were producing.

Note: For those unfamiliar, to take those amazing backyard astrophotography pictures, people take many multiple pictures and use software to align them and “stack” them. More specifically, stacking gives you the best average amount for every pixel on an image. The more images you have, the more noise and artifacts you’re able to remove from the composite image. The result is a far higher degree of image sharpness and detail. The stacking can also have an additive effect, depending on various settings, to make a dim image more visible. The image below of the Whirlpool Galaxy consisted of almost 120 separate pictures.

Whirlpool Galaxy, M51. Images taken with AstoView 90EQ telescope and Nikon D5300. Processed 7-12-2020.

My first thought was, I needed a better scope. Despite the sentimental value attached to the AstroView, it just wasn’t cutting it. So, I bought my most expensive scope, yet, an Orion Ritchey-Chretien 6 inch (White) scope designed for astrophotography.

I began getting better images, but I was still limited to roughly 1-minute exposures before stars would begin to streak. Frustrated, I was glad to move onto planetary targets with this new scope and my knew experience with image stacking. Feeling like I had graduated from my phone, I purchased the Orion Starshoot Mini. It was primarily designed for planetary imaging, but it could also be used for DSOs, as well. I believe that since it was such a new product, it must be capable of producing better images than my Nikon and I could see them much more clearly on a laptop screen than the flip out screen on my camera.

The Starshoot Mini is an excellent planetary camera. But I had a much harder time getting multi-gigabyte video files of planets to align and stack properly in Registax 6, which is used for planetery image stacking, as opposed to DSS. I was able to capture and process my best image of the distant planet Uranus below. But it took hours of trial and error to get such a faint set of video frames to align and stack properly. I also took a stab at Mars and its close approach, but was still new to the setup. Focusing is difficult. So the results weren’t super great. Also below.

Uranus. Processed 12-20-2020. Images taken in late October with Orion Starshoot Mini and Orion Ritchey-Chretien 6 inch telescope.

Mars. Images process and taken in late October 2020 with Orion Starshoot Mini and Orion Ritchey-Chretien 6 inch telescope.

Once Mars began to drift away and Andromeda began to rise into the sky, I shifted to trying to captures image of it with my Nikon. But this time I had the bright idea of repurposing my Orion Starshoot Mini as my autoguider. I purchased an autoguiding scope to fix the Starshoot Mini and attached it to my telescope. I then downloaded and installed PHD2 to act as my autoguiding software. Aside from the initial setup, it’s been pretty easy to use and I’ve been able to take some images with 3-minute long exposures without streaking. For those unfamiliar, the software uses the Startshoot Mini camera to identify a particular star (you select it) and it sends directions to the mount to adjust its motion by tiny amounts to keep that star as still as possible in the camera, or put another way, it keeps the mount following the star so perfectly, the star appears to be still to the camera (image the camera displays on screen).

And now I was shooting long exposures with my Nikon D5300. It only took almost two years to get there.

The setup isn’t perfect, however. Whether the EQ-G mount is just old or could use some servicing, I had to get the balance of the scope and the counterweights as close to perfect as possible or PHD2 will flash at me that it can’t make enough adjustments to keep the scope aligned. It’s something I’m still trying to completely understand, but the results have been thus far promisingly spectacular. See below.

Orion’s Sword, M42. Images taken 12-8-2020 *with Nikon D5300 and Orion Ritchey-Chretien 6 inch telescope*. Variation of image used sometimes as this site’s header image.

Andromeda Galaxy, M31. Images processed 11-19-2020 and taken *with Nikon D5300 and Orion Ritchey-Chretien 6 inch telescope*. Earliest attempt at capturing and stacking long exposure images.

Triangulum Galaxy, M31. Images taken *with Nikon D5300 and Orion Ritchey-Chretien 6 inch telescope* near Christmas and processed 12-25-2020. It’s a little faint but it was my first attempt at this particular galaxy and is comprised of only about 15 images.

That’s where I’m at in my journey of learning to capture astrophotography images with a DSLR camera. And in the coming weeks, I hope to refine my craft more and capture even more DSOs. I even have a wonderful new camera that will replaced my sorely misjudged Nikon D5300, but I’ll write about it later.

That said, once I started seeing this huge leap in image quality from what I had been getting, I re-researched my old Nikon. And it’s a damn fine camera for Astrophotography. If you’re just getting your feet wet with this hobby and you can find a good deal on a refurbished D5300, then you can’t go wrong. It takes great pictures and accessories for it abound, unlike some higher end cameras.

One thing I’m leaving out of this post to save space and time is my experience learning how to process images in Adobe Photoshop, as well as some of the minutia of astrophotography like capturing dark frames. You can’t produce these images without being able to “stretch” the data you’re collecting in some image processing software. The folks at my local astronomy society provided me with a guide early only explaining some of the ins and outs of capturing images, but I learned about processing images in Adobe primarily from experimentation and the YouTube Channel, AstroBackyard.

November 4, 2019November 5, 2019

Use Your Smartphone for Astrophotography

Since getting my old PowerSeeker 127EQ and snapping some quick shots of Jupiter through it, many people have asked me how to do the same. They most often assume it to be a relatively complex thing to do, but it’s not. It’s actually pretty simple and not actually that expensive to get started.

First, you need a telescope. I started with the 127EQ, but I now almost exclusively use my Orion SkyQuest XT8. Both are reflector-type scopes in that they use a mirror to focus the light they receive. Bang for your buck, it’s hard to beat the 127EQ. It’s cheap, has a 6-inch mirror, comes with a sturdy-enough mount, and provides a nice, entry-level viewing experience. Collimating it, however, is a bit of a nightmare. But you can benefit from my experience with doing so.

Saturn, taken on 6-30-19 at 240x magnification with Samsung Galaxy S9. 100 ISO. 1/30s exposure. F1.5 Aperture.

If you can spend three to four hundred dollars, the Orion XT8 is a great scope. It’s a bit bulky, but it’s powerful, offers some surprising optics, and is easy to use and maintain. It benefits from mounting a right-angle view finder and having a strong back to lift it. It’s about 40 lbs.

Be warned. Neither scope will allow you to perform complex astrophotography with a DSLR camera that requires auto-tracking mounts for long exposures. The 127EQ theoretically supports a motor to turn its equatorial mount, but I was never able to get mine to work.

But that’s fine, because this is about doing astrophotgraphy without a headache or spending too much money. You can purchase a much less expensive scope, but those scopes tend to be smaller and less stable. You can’t take pictures if your camera/phone keeps tipping your telescope over or the weight of it bends the eyepiece focuser, which I’ve had happen to a $50 scope I bought for fun that I won’t name.

Once you have a scope you’re going to want your smartphone to have a decent camera. Almost all the modern flagship models from recent years have pretty solid cameras. Most importantly, the cameras have modes that let you manually adjust their capture settings. I started with a Samsung Galaxy S7 and migrated to an S9, which is what I use now. But the new iPhones and Pixel phones are supposed to have even better cameras now.

With your phone in hand, make sure the back camera lenses are clean. Next, open your camera app and look for your image capturing settings. On my Samsung phone, I access these through the “Pro” mode.

Jupiter, taken on 6-9-19 at 240x magnification with Samsung Galaxy S9. 100 ISO. 1/45s exposure. F2.4 Aperture.

The important settings you’re looking to adjust are the ISO, the shutter speed, the focus (manual/auto), and the aperture (if your phone supports more than one aperture). You will also want to set your phone to take as high a resolution picture as it can. The more pixels the better!

The ISO affects your camera’s sensitivity to light. The higher the ISO, the more sensitive it becomes but also the more “noise” you get. The shutter speed controls how long your camera’s sensor is exposed to incoming light. The longer you leave it open, the brighter your image will be. Leave it open too long and your image will blur if it’s moving. When trying to take pictures of planets and other bright objects, you’re going to want to use less ISO and a shorter shutter speed. That generally gets you more color and detail in your image.

The focus is important, too. You can almost always set your camera to manual focus and set the focus distance out to “infinite,” as if you’re focusing on mountains in the far distance. But, sometimes if you have a bright enough and big enough planet or moon, you can play with your camera’s autofocus to see if it’ll work. When it does, the results can be much better than the manual “infinite” focus.

If you can change your phone’s aperture, you should know that the larger the aperture, the more light the sensors receives. The focusing issues with the smaller depth of field from the larger aperture aren’t usually a problem with astrophotography, but sometimes too much light can be a bad thing, especially with brighter objects like the moon and some planets. Trying take pictures with each aperture setting to see what’s returning the best image.

Lastly, learn how to set your camera’s delay timer. Unless you want to invest in a remote for your phone’s camera, the next best thing is setting a 2-5 second delay on taking pictures after you click the button. Even sturdy mounts can momentarily vibrate and wobble after you manipulate your phone and these movements are dramatically amplified at higher viewing magnifications. The timer delay lets these things settle down and stop before the camera goes off, protecting your shot.

Once you have a grasp of these settings. It’s time to purchase a Cell Phone Adapter Mount. This little device connects your cellphone to whichever eyepiece you’re using in your telescope. They range in price from around $10 to $40. The things to consider are the quality of the material, the weight of the mount, how well your phone will fit, and the depth/height of your eyepieces after they’ve been completely slotted into the focuser. If your favorite eyepiece is shallow, pay careful attention to how the adapter you want to use will attach to it. And you want to get the best combination of sturdy material and low weight. I linked the one I use above.

Whichever one you purchase, it will take a little practice and/or some careful marking to be able to slot your phone into the mount in such a way that its camera (note: some phones have multiple cameras on the rear) is center positioned over the lens you mount it on.

In my experience, the easiest way to do this (and redo this because the adapter will probably need periodic readjustment) is to slot your phone and slot a wide angle eyepiece. Meaning, connect an eyepiece with a wide diameter lens. Then open your phones camera and point the combo at a lamp across the room. You should be able to see the lamp on your phone through the eyepiece. If you don’t make some adjustments and try again.

Once you have the wide angle lens good to go, it’s time to refine your adjustments with a narrow angle lens. These lenses tend to be tiny in diameter but offer the most magnification when viewing. Replacing the wide angle eyepiece with the narrow angle eyepiece and check for the same lamp. If the camera is centered properly, you should just get a circle of light in the middle of your screen. If not, make some careful adjustments.

As always, take care not to drop or dirty your eyepieces. Take reasonable precautions before you start.

So now, you have a telescope, you have experience adjusting your phone’s camera settings, and you have an aligned mount. Go find yourself something to take a picture of. It’s easiest to start with a big bright planet like Jupiter, but it’s also pretty easy to shoot the moon. Whatever you choose, direct your scope toward it and focus it for the eyepiece you intend to use for the photo. If you have the ability to tighten up or lock your focuser in place after doing this, then do so. You don’t want it to move for the next step.

Uranus, taken on 10-19-19 at 240x magnification with Samsung Galaxy S9. 200 ISO. 1/10s exposure. F1.5 Aperture.

Now, slot your phone into the mount if it isn’t already slotted. Make sure it’s snug and not going to slip out. Then carefully attach it to the eyepiece with the object in view and in focus. You need to make sure the eyepiece is secure in the focuser and that the mount is secured to the eyepiece, all while not moving your scope. This can get tricky, especially at high magnifications.

For bright objects, you should easily see them appear on your phone’s screen, even with an automatic camera setting. If not, switch to your advanced settings and increase the ISO and/or reduce the shutter speed. The latter usually works better in my experience. Once you can see the object through your phone’s camera, you can begin to make the adjustments to bring out the objects color and detail.

For high magnifications and even lower ones, you’re going to have to readjust your scope to keep the object centered. Whether it’s a star, a planet, or the moon, it’s going to be moving. And the higher the magnification you use the faster it will travel through your field of view. This, too, takes some practice. If you over adjust, you’re probably going to have to detach the mount and find the object all over again unless your view finder is perfectly aligned with your scope.

Note: If you decide to shoot the moon, especially when it’s near full; it’s going to be really bright. Don’t be afraid to increase the shutter speed to hundredths of a second.

Once you have a mix of settings that look good, take a picture using the timer. But keep in mind, what you’re shooting will be moving, so you may want to slightly offset the objects position in your camera before taking the picture to correct for this movement. This can also get a little tricky, but you’re not trying to be perfect. You can always crop the image later. It’s more crucial for “large” celestial objects like the moon or nebula. As parts of them can move out of frame.

Keep readjusting and trying a mix of settings. While I suggested the “Pro” mode, there are new and specialized modes you can also try like the “Night” mode. I don’t suggest taking pictures with the digital zoom. Feel free to use the zoom to adjust settings to bring out color and detail, but zoom back out when you’re done. You can always enlarge the photo later without losing the initial data.

You can be methodical about all of this or correct it on the fly. The photo metadata usually captures most of the settings you’re using. You can even experiment with video, which can be used to get many frames of images for image stacking. Image stacking is a more advanced concept I’m currently learning about it, but it really produces some fine images.

Neptune, taken on 9-7-19 at 240x magnification with Samsung Galaxy S9. 400 ISO. 1/3s exposure. F2.4 Aperture.

When you feel like you’ve taken enough pictures (the more the better), go through them. Zoom in, examine them closely. Try some basic cleanup with a photo auto-adjuster or import them into a more complex application like Adobe Photoshop or some photo editing app.

To summarize, all you need to get into astrophotography is a telescope, which can run as little as $100 or as much as you like; a $10 phone mount; a smart phone, which you probably already have; and some patience and practice.

And to be fair, you don’t technically need a telescope. Venture out to a dark enough place with clear skies and you can manipulate all the same camera settings on your phone or DSLR/non-DSLR camera to take some incredible pictures of the Milky Way or other deep sky objects (DSO).