I’ll be honest. This post will probably take a few days to nail down. There are things I want to show pictures of but I haven’t taken those pictures yet. I might remove this paragraph when it all comes together.

Step one seems to be to decide if tonight is clear enough to warrant the attempt. I live in North Texas and we have pretty decent weather, most of the time. There are exceptions, of course. There is an eclipsing moon behind those clouds.

I have not scientifically tracked it, but I’d be willing to bet a small amount that we have more clear nights than obscured nights.

There are a couple of places where I might set up. Generally, I tend to set up at the end of the driveway, behind the cars.

This gives me a solid and repeatable surface and the evergreen trees block at least some of the direct light from the sodium streetlight on the property. Otherwise, things tend to look like this rather extreme example.

From this spot, targets southeast to northwest have the most open sky. There is a metal metal building to the northeast that limits me to about 10-15 degrees above the horizon, the house is southwest of this spot, limiting to about 25-30 degrees and a big tree is to the northwest. This has not actually been a problem thus far, but I’m sure I will need to try other spots in the future.

At this point, I have not yet traveled to a dark site.

I am also very familiar with exactly where Polaris is from this spot.

After setup, which is assembling and leveling the rig, pointing it generally at Polaris, positioning the power box and a camp chair (and sometimes a fan or heater), it’s time to polar align.

No, wait. I need to focus the telescope and camera first. The new way to polar align using the ASIAir needs the camera to view stars.

There are generally enough stars near Polaris to get focus there. And I don’t have ASIAir home the focus at the end of a session, so it’s usually pretty close already. The autofocus procedure is simple, though maybe a little time consuming. Start the process in the app and it begins by capturing an exposure and analyzing it for candidate stars to focus on. It then ramps the focus up and down over a range and plots the size of that star, optimizing for the smallest size.

The EAF position ranges basically in a 16 bit range, 0 to 65K. Once it’s happy with focus, now I can polar align.

The old way was to start by kind of painfully kneeling low enough to peer through the polar scope on the mount. Consulting Stellarium or some other app for the correct position of Polaris in the scope, I would scoot the tripod to get close then use the wedge screws to dial it in. I would start a timer and check it again in 10 minutes to make sure Polaris is stationary in the reticle.

The new way is not necessarily faster, but it is much easier and I get much better alignment. I start with the laser. It really surprised me in how helpful it is in getting really close to alignment, but indeed it does. Plus, it looks pretty cool.

In the interest of full disclosure, I generally do this laser bit before any of the rest of it, as soon as Polaris is visible. Then I focus, etc.

Then, using the ASIAir polar alignment tool, the controller will instruct you to point toward Polaris and press start. It will take a shot and plate solve it. Plate solving is a method used to determine exactly where the telescope is pointing in the sky by comparing the star field in the image to a database of star positions. It will then move the telescope 60 degrees, take another shot and plate solve that. Then it does some magic math and shows you where you are pointed vs where the North Celestial Pole is.

This isn’t my screen capture, but is a good example. Some people say to ignore the little graphic. I say use it and the directions on the right hand side of the screen. In this example, you need to point the telescope 1 degree, 20 arcminutes (just call them minutes and seconds) and 39 arcseconds to the right (east) and raise the elevation a scant 16 minutes and 41 seconds. A full circle is 360 degrees. A (arc)minute is 1/60th of a degree and 1 second is 1/60th of an minute or 1/3600th of a degree. We are talking very very small movements here. As the screen suggests, within 5 minutes is reasonable, but you will get the smiley face if you get within 3 minutes. Thus far, I have used only the Redcat 51 with all this. I understand that too wide of a field of view makes it difficult for the software to see your adjustments and too narrow of a field of view amplifies your adjustments, making it prone to oscillate either side of alignment. I got to 4 minutes the first time and barely under 5 the second.

ASIAir has an “all sky” polar alignment feature that does the same basic process, but you don’t have to begin pointed *directly* at Polaris. This is intended for when Polaris is obscured by something. I have not tried it yet, but I will soon, just to make sure I know what to expect.

Next, find your chosen target. ASIAir has several ways to do this. Probably the easiest is to use the onboard Star Atlas. It will sort by things that are viewable from where you are. You can scroll and choose something or search. Generally, using the official catalog names are the best way to search, “M31” vs “Andromeda”, for example. The data displayed shows the rise and set times for the object and the relative magnitude (brightness; or really, dimness. Higher numbers are dimmer). You can preview the framing of your image; it knows your telescope and camera parameter, so it can calculate the size and shape of your field of view. Then comes the reason I dropped too many dollars on equipment in August. GoTo.

The mount will slew in both axes to your chosen target, then plate solve and adjust to center the object. It is magic, compared to all the other ways.

Take a picture, long enough exposure to see the object. Once there you can preview again and from the preview, you can choose to rotate your camera to frame the object better and adjust the red ‘target’ reticle to where you want the telescope to move to and choose GoTo again. Repeat this cycle until the object is framed how you want it.

To note, the nebula image above is from the ASIAir’s library, not from the camera at this point. There must be a vast amount of data in that atlas.

Then it is time to start taking some real frames.

Maybe. One advantage of a cooled astronomy camera is that the dark frames and bias frames are going to be very consistent; their purpose is to capture the noise of the sensor at the temperature while shooting. Without a cooled camera, one should take darks and biases with every session, generally at the end. With a cooled camera, however, you can take darks and biases anytime the camera is cooled to the same temperature and reuse them as long as you keep it set to the same temperature. You probably should refresh them periodically, maybe seasonally, when the external conditions can have the most effect on the camera’s cooling capacity. I think I would take new ones if I traveled for a session.

Flats, however, you should capture for each session. Darks and biases are taken, as the name dark might imply, in darkness. Flats instead need a diffuse featureless light to allow the software to compensate for visible anomalies in the optical train, like dust, scratches, etc. There are a lot of flat illumination options, like iPad screens or LED tracing panels. The important thing is that it does not have any image data within it. It’s probably best to take them at the end of a session, but if you’re running it on autopilot and maybe you are comfortably asleep when the session ends, it makes sense to take them at the beginning. Your mileage may vary.

There are a couple of ways to start taking images. The Autorun feature is pretty usable. You can line up several segments of a session, but I had trouble getting it to pause between them. There is probably something I don’t know (as if!), so I tend to put one segment in at a time. I set up and get my flats. Then I set up and get my subexposures or lights.

Here, we are setting up for 10 exposures of 5 minutes each. The image names will be prefaced with “Light”. I don’t fully understand the Bins at the bottom, yet, but I think they are related the use of multiple filters for the same target, for example, LRGB color images with monochrome cameras.

The Meridian Flip option is something I have not done in the past with my guider, but then I may have just been lucky with target choices and the time of day. So, there is an imaginary meridian line directly above you and when your target crosses that line, you should flip the camera over. This is to prevent it from tracking beyond the mount’s physical limits until it hits something. Interestingly, it stops taking shots a few minutes before the flip. I think there may be a “dead zone” of sorts, real or imagined and it’s giving time for the target to traverse that zone before it flips. After the flip, it will plate solve and recenter before it begins taking shots again. Also, stacking software wont care that some of your subs are 180 degrees off from the others. It will correct for the rotation.

The longer a given subexposure is, the better the signal to noise ratio is for that sub. 200 subs at 60 seconds each is not as clean as 60 subs of 200 seconds each, even though they are both 200 minutes in total time. Also, fewer subs will stack faster.

The key to really long exposures is good tracking and the golden key to good tracking is autoguiding.

Tracking, like my SkyGuider Pro does, is an open-loop process. The motor and gears in the guider run at a predetermined speed so that the mount moves at the sidereal rate, the same rate the the stars appear to move due to the earth’s rotation. You can get pretty long exposures that way. It works and it is simple and reliable.

Autoguiding closes that loop, giving the motors feedback to fine tune the motor speed continuously. Some guiding solutions have a separate small telescope with a, typically, monochrome camera. My ASI585MC actually has a built in guide camera at the same focal plane as the main camera. This eliminates the need for a second scope, ensures that the physical alignment of the guide camera is not subject to change, like a loosely mounted guide scope might introduce. The drawback to this method is that the guide camera is subject to any filters that may be installed in the optical train. In my limited experience, it hasn’t caused guiding to fail.

The guiding performance is displayed in a running graph.

The traces show the measured error in the guide star position, how far it is off from where it ideally should be. You want both of them as small and smooth as possible. The graph auto-ranges and honestly, this chart shows a pretty wide error rate. It should be below 1 and the lower, the better. I do need to work on improving the guiding and I have some things to try. For one thing, there is a calibration routine to perform and I have learned that I am not doing it the right way. YouTube is a treasure trove of such tutorials.

In any case, I was able to get clean 240-second long subs of the Western Veil Nebula, NGC 6960. This is on of the first subs taken after the meridian flip, which is why it appears upsidedown compared to the framing images above.

This is also my second capture of the Veil. The first was made with 240 subs of 60 seconds each, with no filters. This image above is a single 240 second sub, with a dual narrow band filter in place. This single image is almost as good as the stacked and post processed 240 images. Narrow band filters are the ticket, and they also “accidentally” filter a lot of light pollution, even moonlight.

There is another awesome feature of ASIAir that really helps with capturing the same target over multiple nights and it’s almost deceptively clever. Simply locate the last image (ideally) from the previous session and click GoTo.

It will plate solve the image to locate it then slew the mount to the same position and centering! Now you just continue shooting. Well, as long as you haven’t rotated the camera since the last session. Even so, you can do it, you will just have to work at getting the same rotation, at least close enough for stacking registration to deal with it.

This is the stacked and processed image from my first Veil capture. It was 240 subs of 6 seconds. I had 30 each darks and flats. I took 30 flats using an ipad for illumination, however because it was a clumsy procedure, I had to discard a couple of them at processing time. Still, it’s a decent picture:

This is the second Veil capture, with 60 subs of 240 seconds and a dual narrow band filter in place. This one is cropped to eliminate some of that empty space at the top of the image, but the uncropped version is framed exactly like the original.

Notice how much more detail is shown, especially the wispy blue stuff.

The plan is to capture another night or two of long exposure subs. If the guiding and skies will support it, I plan to do 300 second exposures.

My goal is to produce my own image not unlike this one, from the Wikipedia article on the nebula. I think I just need to capture much more light to do so.

My astrophotography hobby has been an interesting stair-step ride to more and more capability and automation (and dollars). I have reached a plateau that should hold me for a while.

First, I took pictures of the Andromeda galaxy with my DSLR, a 70-300mm kit lens, and a fixed tripod.

There are certainly pictures done better with similar equipment, but this one is mine.

The first major upgrade was an iOptron Sky Guider Pro and ball head. For the next year or so, I worked with this setup and it worked pretty well. Looking back, it seems I was maybe a little obsessed with Andromeda. Here is one captured with that rig, stacked with Deep Sky Stacker and post processed with GIMP.

Another year or so and I painfully bit the bullet and got a real telescope, a William Optics Redcat 51. It was about $850. While it was really hard to get me to click go on that, I have been very happy I did. It is a great scope.

With it and the DSLR, still using DSS and GIMP, I got really decent captures of the Orion nebula and a couple of others.

I also used it to get the April 2024 total eclipse.

Orion and Pleiades were captured with the assistance of a laptop running BackyardEOS. This had it’s pros and cons. The biggest issue was the kinda kludgy way that I had to run it.

This is literally during the Pleiades capture shown above. I dragged out another camp chair to sit in facing the laptop. There was the USB between the camera and laptop and power for the camera and dew shied heater. This convinced me to pucker up again and get an ASIAir, though it would be summer before I pulled the trigger on it.

Life intervened. Lost my job of 21 years and my car engine blew up. I was unemployed for 5 months, then once reasonably sure they were keeping me, I put a new engine in the car. Ironically, I would only attempt a couple of captures with it and for reasons unrelated to the ASIAir, they were iffy captures. One was almost all subs with a foggy lens because I just forgot to turn on the dew shield heater. I forget the others.

But it had been long enough now to consider upgrading something and what made the most sense was to get a dedicated astronomy camera. I chose the ASI585MC Air. This unit has a cooled main camera, a built in ASI220 guide camera and an ASIAir controller. As much as I love this camera, it was quite a butt pucker to place that order. The camera, even with an open box discount, was $900.

A mere couple of weeks later, I elected to get an autofocuser appropriate for my Redcat 51, which is the first generation with helical focus. Now that it is in place, I think I prefer it to the rack focuser, as least as far a compact package goes.

With this rig, I revisited Andromeda, but between light polution and just electing for a less than ideal amount of exposure time, it wasn’t a good capture.

I had long disliked the adapter that connected the telescope to the declination arm of the Sky Guider Pro. It is a solid steel piece, nicely machined, but its basically a twist and set the locking screw kinda thing and it makes it very difficult to do final framing. I decided to build up a solution for that. Sadly, it was never tested.

Once again, the equipment bug bit me and I pulled the trigger on a Skywatch Sky Adventurer GTi, a mount with go-to capability, and a couple of dual narrow band filters.

So the rig as it sits now has auto focus, autoguiding, a mount that can get me to a target and a controller to run it all and automate capturing subs. That is a long way from that stationary DSLR pointing at Andromeda.

I made the mistake 🙂 of adding up the major items. I am not counting various cables, cable management, and certainly not counting my Bluetti power box. Even so, including the original DSLR that predated the hobby by five years, I have spent a total of just under $4800. That is the entire journey, though, and many of those things are not part of the current rig anymore. That was, itself, $3100. Sadly, $2300 of that was purchased over a 30 day period this year. Ouch.

The first astro specific item was the SkyGuider, in June 2022. If we divide it out to the last purchase, it’s only $3.13 per day. Plus, I do still have the DSLR and SkyGuider. I might set up both and do a comparison capture. Actually, that sounds like fun.

Next post, I will go into some details about the new workflow.

Ok, it’s not *that* important…

I have bought a LOT of stuff online. Some, such as my wife, would say I have bought too much stuff online. That isn’t exactly what I want to talk about.

Most merchants will semi-randomly send an email asking for a review of some recently purchased item. Often, may usually, they are asking for a review of some extremely mundane thing that was *also* ordered with some fairly major purchase. One of my favorites is when I ordered a CyberPower UPS for $240-something dollars and in the same order, I had a small pack of washers, not even fancy washers. Plain ole’ mild steel washer with a zinc coating. Guess which item they wanted a review for?

I had a similar thing happen recently. I ordered my ZWO EAFN and accessories from Agena Astro. The EAFN was $180 and the (arguably unnecessary) ZWO focus hand controller was $30-something. The email wanted me to review the hand controller.

So I did. Admittedly, I had Claude.ai give me a framework to build on, but here is my review of the ZWO EAF Electronic Automatic Focuser Hand Controller:

As mentioned earlier, I ordered a Vixen clamp with a 1/4-20 threaded hole to interface between the rotating platform. It’s not red, but it still works 🙂

Nothing makes dust show quite like a bright camera flash.

I also got a glorified laser pointer to help with rough polar alignment. This is a Move Shoot Move product specifically for the iOptron Sky Guider Pro.

Argh. The dust. Obviously, there is some cleaning to be done and when I leave the rig assembled in the living room waiting for clear nights, it needs to be covered.

Anyway, as of this writing, I have not yet tried out either accessory.

Of course, I am already considering a mount upgrade. To be honest, I have thought about it for a while, ever since it became obvious that locating targets can be challenging. It makes no sense to upgrade at all if it’s not one that is go-to capable.

The preference would be for a ZWO AM3. It wouldn’t need any counterweights, which would keep the rig compact. It is elegant. It is red. 🙂 There are, however, 1500 other reasons to shop around. Nice as they are, the price would tough for me to justify.

The most economical go-to mount today seems to be the Sky-Watcher Star Adventurer GTi. The retail for about $580. A kit that includes a tripod would be about $680. This would enable other features of the ASIAir software, as well.

I could attempt to recoup some of this cost by selling my iOptron SkyGuider Pro and tripod, and my redundant ASIAir Plus. All tolled, I invested almost $1000 for these items and the accessories they would include. Perhaps I could get $400-500 for them. That is most of the way there.

One of the things that has bothered me about the whole rig for a long time is aiming in declination. Currently, I am using a steel mounting block that came with the SkyGuider. It is pretty secure, but the thumbscrew locking method frequently results in it moving after carefully aiming it. Also, if the particular right ascension position has it leaning very much, then this mounting block can be difficult to secure because of the way the the mounting block thumbscrews want to seat in a groove, but the whole assembly is trying to wedge out of said groove.

This has been a bother since day one. So much so, that three and a half years ago, I ordered a Sky-Watcher Star Adventurer declination bracket. This is designed to fit, perhaps obviously, the SkyWatcher Star Adventurer. Importantly, it has a rotating platform for the rig to mount to.

While this picture is obviously intended to spotlight the rotating platform, it is technically upside down. 🙂

Sadly, I could not figure out a way to attach this whole assembly to my SkyGuider. I recently decided that the best way would be some kind of right angle bracket. I shopped for some suitable sort of commercial bracket, to no avail. I realized that I should just make one.

The four screws attach the bracket to the top of the iOptron dec bracket.

Then the rotator is attached to the top of the bracket.

Note the clutch ring. Loosen the clutch and your can freely rotate the rig. Tighten the clutch, then the knob on the side turns a wormscrew to fine adjust the position.

This assembly was completed just last night. Weather permitting, I hope to try it out tonight.

For the moment, I have it clamped into a 1/4-20 hole on the bottom of the dovetail rail. Happily, there is a hole very near the balance point, but I would still rather have it in a dovetail clamp.

Of course, I have a dovetail clamp of a sort. This one is made to attach to the bottom of the ASIAir Plus and connect it to a Vixen dovetail plate. It has crossed slots in it. The 1/4-20 stud on the turntable isn’t long enough to reach through the slots to a nut. I ordered one that has a suitable threaded hole, but I am prepared to modify this one if that doesn’t work out.

The camera arrived without drama.

Before the ink was dry on my last post, I decided to deploy an autofocus system for my rig.

I presumed that sticking with ZWO for components that chat amongst themselves is probably a good idea, so I ordered a ZWO EAFN, a manual focus controller, a temperature sensor, and a Buckeye Stargazer mounting bracket, all from Agena Astro.

Since the ASIAir built in to the camera has its own ambient temperature sensor, this one is probably redundant. It is intended to let the autofocus elect to exercise focus based on a somewhat configurable change in temperature. This sensor is designed to plug in to a headphony looking jack on the EAFN, the same jack that the manual focus dingus plugs into, and it presumably reports to the automation via the USB. It could arguably be more true to conditions by sampling air temperature somewhere besides inside the cooling airflow for the SmartCamera, but point is to detect a rise or fall in the temperature, not necessarily the exact temperature *number*.

In any case, the stuff arrived, as did the camera itself.

Mechanically, the installation went well. I had only one real hiccup, and that was based on my own assumptions of how things should be, as opposed to how they are. 🙂

The T2 adapter to connect the Redcat to the Canon camera has an adapter ring that is secured to it’s base with three little grub screws. This has been in place ever since I first received the Redcat 51 in July 2022. More to the point, it had been on there long enough for me to forget that it was not connected to it’s own screw ring adapter. I tried for far too long to unscrew that single piece of nicely machined aluminum.

In the end, there is a 48mm to 42mm adapter ring that steps down the tube size between the telescope and the new camera, connected to a 21mm extension and a 16.5mm extension.

The focuser was generally a very easy installation. The Buckeye Stargazer mount components are all quite obviously 3D printed, but are also quite sturdy. The ring that goes around the helical focus ring is printed in TPU or some sort of flexible filament, so it has a tight but compliant fit over the focus ring’s rubber grip. The only thing I didn’t care for is that the rubber on the focus ring tended to flow and bunch up in front of the TPU ring while I was pushing it into place. Installation was thus a little bit fussy, but in the end, it is on there quite solidly.

I had the rig outside setting up and getting ready for nightfall. While I had it out, I played with terrestrial images for a bit, mostly to get familiar with the camera and ASIAir. It works quite well.

Happily, it was a clear evening and polar alignment was successful, other than the procedure’s affect on my knees. 🙂

Unfortunately, focus turned out to be the problem. The autofocus procedure needs some contrast to work with, so you need to manually focus to at least where you can see stars. It took me a while to nail down that with the focus ring nailed to lock beyond infinity, I still had fuzzy round blobs.

I took the rig inside and starting measuring stuff, backfocus in particular. Backfocus is the required distance between the sensor and the final ocular lens. Most other telescopes have a corrective pack of lenses called a field flattener. This is to ensure a sharply focused image across the flat sensor in the camera. By some agreed standard, this distance is typically 55 millimeters. The Petzval optical train design produces a flat image as is, so is not particular sensitive to the specific backfocus distance, and that if you can achieve focus, all is good. That said, most forum posts said to basically don’t worry about it as long as you can focus. There was the occasional mention of a 59.X mm distance involved with the Redcat 51. With the extension tubes I had in place, mine added up to 55mm, which *should* work but obviously wasn’t.

I elected to order an extension tube set to stretch it out. The SVBONY set from Amazon was inexpensive and includes, 5, 10, 15 and 20 millimeter tubes.

i had also ordered a filter drawer so that I would not need to disassemble everything to install a 2 inch filter inside the telescope. They are purposefully designed at 21mm to replace a 21mm extension, which is exactly what I did.

I went conservative and added only the 5mm for the next night. Turns out, I could not get it even to the round blob stage. It simply didn’t occur to me the night before to try *shortening* the extensions. I removed the 5mm and 16.5mm tubes, replacing them with a 10mm tube and tried again.

Success!

Now to try out autofocus.

Now I started taking a few randomish shots looking for the Andromeda galaxy. Upon reflection, I probably should have tried for a nebula, but the sensor size on the 585MC camera gives the rig an effective crop factor of 3.4. Crop factor is ratio of the sensor size you are using compared to the “standard” sensor size that is basically identical to 35mm film. In DSLR cameras, this is the “full frame” sensor. Because a smaller sensor is exposed to a smaller portion of the image, it is effectively magnified, assuming the pixel sizes are appropriately small. The crop factor can to applied to the focal length of the lens to determine the effective focal length of the combination. My Canon Rebel T6 has an APS-C sensor. APS-C is “Advanced Photo System type C”, something I learned today days ago. Anyway, the formula to calculate crop factor takes the pixel size as well as the height and width of the pixel field into account. The APS-C sensor gives a crop factor of 1.6. In practical terms, my 250mm Redcat 51 will perform like a 400mm lens (250 x 1.6) on the Canon. Similarly, the smaller sensor in the ZWO, with its even smaller pixels, will perform like an 850mm lens (250 x 3.4). Thus my interest in capturing Andromeda, to compare it to my previous Andromeda captures.

The plate solve feature in ASIAir turns out to be handy, though not quite as handy as I wish. Using Stellarium, I found the Ra/Dec coordinates for Andromeda. Using the plate solver, I found where I was pointed. This helped me walk my way to Andromeda maybe a little quicker. In any case, I found it.

I am new at the ASIAir thing, so I may or may not have done this the best way. I configured Autorun to get 40 bias frames, 40 flat frames, 40 dark frames then 480 light frames. The bias frames were easy, just leave the cap on the lens and pause the Autorun when they were done. For the flats, I didn’t want to move the rig since I had found Andromeda, so I used a white cloth illuminated by my LED flashlight, again pausing Autorun when they were finished. Darks were super simple, cap on and just watch the progress for 20 minutes until those were done, then simply remove the cap and let the lights go. I set it for 480 x 30 second frames.

Too bad my polar alignment wasn’t that great. It appeared solid when I set it. I generally set in in the polar scope then check it 5 or 10 minutes later to ensure that Polaris is still in the proper place within the reticle. I suspect that I unknowingly bumped the tripod after that, maybe in capping and uncapping the lens.

It wasn’t off by a gob. Andromeda slid off the screen very slowly, about an hour the first time, as in by the time I had noticed. I went out, paused the Autorun, reaimed and started it again, understanding that the capture was going to be compromised. It was, however, midnight, and I didn’t want to start over completely. This was largely going to be a shakedown cruise anyway. Looking at the lights, it seems like it took it about 2-3 hours for Andromeda to ooze out of frame. While not ideal, I suspect most of them will still be able to stack, even with very slightly elongated stars. Shorter exposures, even a lot more of them, may have avoided the TicTac stars, but the target would still have crawled off the frame.

And in the interest of full disclosure, I still haven’t processed that session.

The next morning, I found the telescope pointing very high in the sky, but the power cord had snagged on the top of the SkyGuider. It might have been able slip off had the power switch not been raised. I mused about how funny it might have been had it actually powered itself off. Sadly, it did not.

It has been a bit more than a year since I posted the October 2024 eclipse story. I have not been super active in astrophotography, but I keep informed via YouTube and Discord.

Last night was the first astro attempt for several months. Short version, skies were mostly clear except about where Polaris is, so polar alignment did not happen within the hour or so before I gave up on that.

Instead, I turned to the almost full moon. (Yes, even with a full moon, I was going to try for a nebula somewhere) I had recently looked up some tips on lunar photography with my Redcat 51 and wanted to give it a try. The short version of that story is that I was able to snap a couple dozen frames. The previews or thumbnails looked promising, but the actual images were really blown out 🙁

Discussing this with friends in a Google chat, it occurs to me that, while astrophotography can start pretty cheap, especially if you already have a DSLR, the vaguely defined rules of time-effort-money apply. You can generally save one, but not all three.

Much of this chronology was discussed in an earlier post, but this time, the theme is the costs.

In my case, I started, with no concept of hobby astrophotography, with a Canon EOS Rebel T6 that I bought from Meh in 2017. Meh frequently has weird deals. I think they basically buy closeouts and get what they can for them. Sometimes it’s some protein bar, sometimes is a backpack, sometimes some oddly specific smart home light bulb. Almost always something that probably didn’t sell somewhere else. I’m not sure why they had a truckload of not really that out of date Canon cameras, but it was a bundle that would be $550 retail that they were selling for $340-something. For me, it was really intended to replace my film photography hobby from decades earlier. I did some minor accessorizing, such as getting a 70-300mm lens, a 500mm reflector lens which is actually not a great lens, a tripod, etc. I would take a number of decent pictures with it, but it didn’t really light me up until 2021 when I discovered the decoder ring that was Nico Carver’s “Nebula Photos” YouTube channel. I am not sure how the algorithm linked me up with astrophotography, but it did. The thrust of the video was how to do this on almost no budget, assuming you already had a DSLR camera.

Using the Rebel and a tripod, I followed the advice in probably this video to capture a very basic but not terrible picture of the Andromeda galaxy. This was untracked, stacked with Deep Sky Stacker and tweaked with GIMP. It was fun, but untracked, with a not particularly awesome 300mm zoom lens meant short exposures. Still, I was hooked.

The first dedicated astro gadget was a tracker, the iOptron SkyGuider Pro. It was $488 in July 2021. Now I could do much longer exposures and generally had better luck. I think it took a couple of sessions to get a decent Andromeda.

I also seem to do my upgrades in the summer and maybe July specifically. July 2022 brought the really big upgrade to the William Optics Redcat 51 telescope, the older one with the helical focus ring. It was $844, which for me was quite the sphincter pucker. I would not have much to show for it until January 2023, when I got my most favorite capture thus far, the Orion Nebula.

January 2023 also got me very nice picture of the Pleiades cluster.

The heavier Redcat was slightly more sensitive to my plain Jane tripod. It was a nice enough tripod, just not as solid as was needed for astro work. I ordered the iOptron tripod to fit the SkyGuider Pro in November of 2022, for just over $100. It was backordered and didn’t ship until January 2023.

The rig was pretty stable for a while. This is is the basic rig used for the October 2024 total eclipse. The external monitor was very nice for the eclipse, keeping me from bending in unlikely directions to view the camera screen. I don’t often go to the trouble of setting it up.

I took a bit of poetic license in assembling this composite. There were some passing clouds between third and fourth contact, so I used the sequence from first contact to totality, then mirrored them for the bottom half of the pic. I have also just noticed that this specific version shows an artifact of my manipulation. I have a version that is clean. 🙂

As mentioned in a different post, I picked up a Canon EOS Rebel T5 camera body. It was just under $100 from Adorama. I have used it mostly as a “replacement” for the T6 for casual photography, but I have always thought I might send it off for a full spectrum mod.

From here, I spent a good deal of time and some money on storage, mostly in the form of knock-off Pelican cases, some from Harbor Freight, some from Amazon. I currently have a case that holds the Redcat and the stuff attached to it, a case for the SkyGuider Pro, a biggish rolling case for most of the accessories and the camera itself. The accessories have not specifically been inventoried or priced out, but it’s stuff like battery eliminators and chargers for the Canon cameras, intervalometers, filters, cables, cable management stuff. Probably a couple hundred bucks worth of stuff, but I haven’t gone to the trouble to add them up. I predict that I probably will someday.

The next upgrade was something that I had watched for a long time and nearly purchased several times, a ZWO ASIAir controller. I ended up with the ASIAir Plus with 256GB of storage. I already liked using laptop software to control the capture, even if I had only done it a few times. The idea of being able to set up the rig and retire indoors, away from winter’s chill or summers insects was very attractive.

Most of the astro specific gear I have purchased thus far was from High Point Scientific, or sometimes Amazon, but the ASIAir came from B&H Photo. The controller was $350, but the whole order came to about $500 because of accessories, like a dovetail clamp for the ASIAir and some high performance SD cards. As befits my habit, this was ordered in July 2025.

It would be February of 2026 before I actually tried to capture anything using it. My stepdaughter and her hubby came out, ostensibly to see the planetary alignment, but we wanted to try to get some nebula or another while they were here. There was a bit of a learning curve with the ASIAir, but the ultimate failure of the capture session was down to bad viewing conditions. Often, the world fails to meet my expectations.

Work has kept me busy enough to not have much astro time since then. However, it’s July again, so…

Although I haven’t specifically had any *problems* with tracking, I have still been low-key shopping for a guide camera to further improve tracking and maybe up my exposure times another notch. Longer exposures mean more light on the sensor and more light means improved signal to noise ratio. Some guiding options are actually not terribly pricey, at least compared to $500 for this or $800 for that. It should be obvious that plan won’t work for me.

I weighed what I was willing to spend on a payment plan vs what was available. In the long run, I have decided to shrink the rig a little more by going with a smart camera, the ZWO ASI585MC-Air. I found an open box deal, so it came to, you guessed it, about $800, including an accessory or two. The ASI2600MC-Air, with its huge 21MP sensor, would have been my preference, but I wasn’t ready to pay nearly double for it.

This little monster has an 8MP cooled color camera and a 2.1MP guide camera that both sit in the same focal plane, eliminating the need for a separate guide scope and camera and the attendant cabling. Furthermore, it has an ASIAir controller built in, eliminating the ASIAir controller, the Canon camera and their power and control cabling. All in all, it should be a clean and compact deployment.

On paper, the 8.1MP ‘585 sensor is arguably less impressive than the 12MP sensor in the Canon, but the ZWO camera has two feathers in its cap. First, the WxH resolution is smaller, but the pixel size is significantly smaller, meaning a sharper image in that resolution. A Canon image cropped to the same width and height would still not be as sharp. Also, it doesn’t have the kind of infrared filtering that a DSLR has, making it better suited to the red and near infrared from emission nebulae.

On that subject, after I placed that order, I remembered that I wanted to get a dual narrow band filter with it. Our property used to show as Bortle 4 on the common light pollution maps, but in the last year or two, that has gone up to Bortle 5. That, and we have sodium and mercury lights in the neighborhood, especially including a sodium light on our property. These and my interest in emission nebulae have informed a desire to try out a dual narrow band filter. I ended up ordering an SVBony 7nm filter from Amazon. So there went my open box savings 🙂

The filter will probably arrive Wednesday, but the camera will be Saturday.

As for any future upgrades (and lets not pretend I won’t) I think it will either be a mount upgrade, which would require some kind of a go-to capable mount or, perhaps cheaper and more likely to come first, an electronic focuser. Focusing the Redcat, with the helical focuser, can be tedious. Automating that should help minimize setup time. I don’t really see a need to change telescopes to something with a rack and pinion focuser. Although… if I were to do that, it would also have to be an upgrade otherwise. Just getting the newer Redcat 51 wouldn’t make sense, but a telescope with a bigger objective *and* rack focus…

Stay tuned.

I’m sure my eclipse day story is not much different than untold thousands of others, but I only have mine to tell. 🙂

My long long time friend KD and I started loosely planning for an eclipse capture trip quite early, as one should. Actually, we started planning for the October 2023 annular eclipse. We both live in Texas, but a good four hours apart and neither of our homes were directly on the October 2023 path. Soon, however, I realized that I already had conflicting plans for that week, so I missed that one. That made April 2024 that much more important. I had vacation time to burn, so planned for Monday and Tuesday of that week so that I could do whatever travel I wanted to do.

As we got closer to the date, we tried to find a place that was a similar daytrip drive for both of us and it was looking likely for a lonely stretch of highway near Llano. Conditions changed, as they often do, and KD was going to be able to make it more than a day trip, so I started looking for places closer to me, intending to host him here. As it turns out, the path passed through a town near Sulphur Springs where I know someone who owns a bit of land. I contacted her and a couple of astrophotography nerds were just the thing she needed to complete her eclipse day plans. She asked for our T-shirt sizes, so I knew something was up. 🙂

The other part of planning that I was partly successful with was the two part task of getting things together for the shoot and practicing with them. I was better at gathering than having 😉 Of course, the gathering was done in time for the October eclipse.

The general plan for the day was to use my Redcat 51 telescope and venerable Canon Rebel T6 with a solar filter and an intervalometer to take about one picture per minute and use my tracker to make it easier. Happily, for that part of the plan, all I needed to purchase was a solar filter to fit the Redcat.

I also wanted to have an second camera for manual use. I found that I could get decent price on used Canon cameras on Adorama. They had a Rebel T5 for less than $100. The T6 has WiFi and NFC and a higher resolution screen, but otherwise the T5 is essentially identical to the T6, making them largely interchangeable for most of my uses.

Editors note… for reasons I can’t explain, I am picking up the editing of this post almost a full year after the event and everything above this paragraph was written a year ago. It just shows that if I don’t jump right on a blog post, it suffers.

Another editors note, added in the summer of 2026… This blog entry was posted in early April 2025. Near the end of the month, KD, my friend of about 50 years, was in a stack of situations for which he saw no resolution and chose to end his own life. That does not affect this specific story, but it highlights how quickly things can change and that you should never assume you know everything going on in someone’s life.

Now it just came down to making sure that KD and I coordinated our travel plans and that we gathered pretty much everything vaguely photographically related that either of us own. He came to our house a day early and the morning of, we headed to North East Texas. After all the introductions were made, it came to light that the proprietor had indeed made a small event out of it and had lunch and T-shirts for a dozen or so guests.

We set up all of our gear. With all the boxes and bags we brough in, it looked like we were there for a movie shoot. Sadly, I did not get any good detail shots of the gear once it was set up, just this wide shot of the site.

In the foreground is KD’s setup, a Canon DSLR and filtered lens on a tracking mount, secured on a weighted tripod. Behind is my setup, similar in that it is a Canon DSLR and the Redcat51 with a filter on a tracking mount secured on a big tripod, but not weighted. In the rear is someone else’s camera on a tripod.

One of the things we were concerned with was polar alignment for the tracking mounts without being able to see Polaris. Using just compass directions fine tuned with smartphone apps, it turned out to not be a big deal. We sighted down the axis of the tracker along the compass line and tracked the sun pretty well, making a couple of small adjustments to tune it in beforehand.

The setup as we approached showtime felt pretty dialed in. Besides, what were we gonna do, start over?

I had my intervalometer set to one exposure per minute, and I was setting exposure manually in the camera. I had an external HDMI monitor connected so that I could preview images and do these exposure settings thanks to KD bringing one for me to use. This was SO handy that I immediately purchased one of my own after this event.

When the schedule app we were using gave us the warning for first contact, we got ready. I started my exposures *at* first contact, which technically was not yet visible to us, especially to the naked eye.

My setup tracked really well. I did have to reframe a few times to keep the image centered, so polar alignment was not perfect, but it was definitely good enough. I tweaked exposure a few times, especially when we had a few clouds pass through, which did happen several times, especially after totality.

So, yes, the clouds had us very nervous around totality, but if I recall correctly, we got all of totality cloud free. Or at least, if we had clouds, they passed quickly such that totality was not ruined by them. I would need to check all the images. As mentioned above, I am editing this post a full year after the event :/

There were quite a few clouds between the end of totality and last contact, enough so that I had to kinda cheat for my composite image of the event.

The top half images are first phase images. Because of how many second phase images were obscured by clouds, I could not really mirror shot for shot like I wanted to, so I cheated and just mirrored the first phase images completely for artistic reasons.

A good time was had by all. Yes, we are posing with Moon Pies.

For a couple of months, High Point Scientific had my new tripod on backorder. It is apparently quite popular, being solid yet inexpensive. I was pretty excited to get the notice that it was shipping.

As it is winter and Orion is quite prominent in the night sky, I thought it would be nice to capture the Orion nebula. Because of it’s location, basically formed around Orion’s dagger, it should be easy to find, at least compared to many, maybe most, deep sky objects.

For my first try, I had my CLS filter in place. We have a big sodium light that is basically in the same direction as Orion when I am set up in what is arguably a very handy place, in my driveway, just outside the garage. This filter, however, is pretty dark and it made it more difficult to find anything. At some point, I decided that maybe I was pointed the right direction and that I just couldn’t see the nebulosity in my test shots, so I set the thing loose taking 180 x 30 second subs. I spent some of the capture time in the house doing things that needed doing and some of it waiting in the car with the heater on, which was kinda novel.

I had started a little later than planned, plus all that attempting to find a nebula push my capture kind late. The exact place I had set up was inadvertently planned for my capture plan. This was where the camera was pointed at the end of 180 frames.

I captured a really pretty field of stars and I had only missed the nebula by this much:

As luck would have it, a couple nights later was clear and a Friday, so I set up again. This time I removed the CLS filter, hoping it would make it easier to find the nebula. I am not sure whether or not it made a real difference, but I did find it!

It was very exciting not only to see the nebula show up on the viewscreen, but also to be able to frame it so perfectly.

I captured another set of 180 x 30 second subs, about 30 darks, flats and bias. I set up a little bit out in the yard to keep from catching the house if capture went long. I also set up a heater and for the most part, sat with the equipment for most of the capture time.

I also ran a small test of two other bits of equipment, a dew heater for the astrograph and my Bluetti power station. While the power station was not purchased specifically for astrophotography (power loss during winter was the big thing), using it for possible dark site travel was a consideration.

This was the first time I had even powered up the dew heater. According to the Bluetti display, on high, it draws 6 watts. I could hardly even tell it was warm against the aluminum dew sheild of the Redcat. I suppose that all it has to do is keep it just warm enough to discourage condensation. Shrug. Whether or not it was succesful would come up soon enough.

We had plans for early Saturday afternoon, so I decided to stay up and do at least a preliminary stack of the capture. I scrolled fairly quickly through the subs and discovered a couple of where I presume I had bumped the tripod and excluded those subs. The final stack came out… ummm… odd.

This is after a bit of stretching in GIMP. There are two anomalies about this image. The most obvious to me is that the bottom 1/3 or so seems blurred, out of focus. I had run through checking the subs pretty quickly, but certainly none were way out of focus. It also strikes me as odd to only be out of focus on the bottom of the image. The top and middle seem to in sharp focus.

The other thing, and this was harder to notice because of the blurring, but there is a definite linear gradient from top to bottom.

It was too late and I was too tired to do much about it just then, so I hit it again the next morning. One of my more careful trips through the subs, I noticed that several towards the end of the capture seemed to have soft focus, so I excluded them and it was essentially unchanged. I reviewed my flats and noticed that they had a linear gradient to them and thought, oh, that makes sense, so I restacked again without flats: no change. It occurred to me later that I may have unchecked all the flat captures, but maybe not the flat master that the previous stack process created.

I posted a png of the stretched blurry image on the Nebula Photos Patreon community page, with some details about the capture. Nico took an interest and a few private emails later, I had much more carefully tried stacking without the flats. I cleaned all of the .info files out of the lights folder, moved the exclude lights to another folder, as well as moving the master flat to another folder. When I stacked this time, it was 131 lights, zero flats and the presumably good dark master and bias master. The image came out great and with a couple of stretches and a crop:

My favorite astro image thus far!

To further verify that the flats were the issue, I kept all the rest of the conditons the same and added back the flats and I got this different image. It may seem to be ok, but upon closer examination, it is still very wrong.

It is hard to tell at full size, but the bottom half of the picture, getting worse as it goes lower, the stars split into three divergent images of red, green and blue.

I will be the first to admit that I do not understand the inner workings of Deep Space Stacker and how it uses the calibration files, but it now seems obvious that if there is an issue with those files, it can damage your final image in probably unpredictable ways.

Some of the discussion with Nico was about my flat capture process and I am going to rework how I am doing that. For this session, flats were captured by holding a USB tracing pad up to the end of the dew shield and adjusting exposure until it was just a little underexposed, which turned out to be 1/2500″. This is probably way too fast and catching a pattern of sensor noise as well as PWM flicker and shutter artifacts from the brightness control of the panel itself.

There are several ways to address this and I will report on what works well for me.