Again, Cygnus is not really my first thought when it comes to open clusters (at least, not ones that seem to have no nebulosity surrounding them). But this cluster could rival anything in Auriga. And the pairing the the (obviously much-more-distant) NGC6946 (see other post from today) just really makes it a wonderful target.

This one was a “freebie”; I was aiming for the galaxy. But the planetarium software said there was a big cluster here, so I framed it in. Very nice.

Cygnus is not generally the area of sky you think of when you think “hey, showpiece galaxy”. But here you go. NGC 6946 has been dodging me for years, so I decided to grab it.

When I pointed over there with the planetarium software, it turns out that there was a huge open cluster right nearby, so I framed them both.

3 bright field stars, too — I mean, seriously. What a gorgeous panorama!

Here’s the whole field. I left the scope running around 1am, and let it go all night. By sunrise, I’d captured 20 frames; I tossed the final one because it was a little sunrise-y. So 190m total, 3h 10m.

And here’s a detail of NGC 6946. It’s a really gorgeous face-on spiral, looks a lot like M101 to my eye. Cool!

I will post the cluster separately, so it’s easier to search for.

20m subframes were slightly trailed, so I stuck with 10m. Didn’t lose a single one due to tracking errors. Thanks, 4026!

Normally, I don’t go in much for edge-on galaxies.
I just don’t think that I really get enough pixels to work with for the amount of effort that goes in.

But NGC4565 is huge. So I decided to give it a shot. What with one thing and another, I didn’t get started on the object until it was right at the meridian, so I only got an hour of it before I ran out of time.

But, not too bad.

The caption in the photo is incorrect; this is a one-hour (6x10m = 60m) integration. Oops.

Here’s a close-up (1500×1000 -> 900×600 crop):

This object is worth chasing with Cassie, and also worth a bit more integration time. Also, plate solving. I’ll get to it.

Another night hunting galaxies in Virgo. This time I went after M100, which I was pretty certain to be a spiral.

I had some initial difficulty getting Elbrus working. It took about an hour to get the plate solving working. I have to manually calibrate 3 stars everytime, and even so, it had trouble locking on. I started to streamline this process by writing down the positions of favored alignment stars, but there must be something that I am missing.

Once Elbrus was locked on, everything went smoothly. I set up on M100, was able to poke the scope a little to get a couple more galaxies in-frame, and we were off to the races.

I picked up 45 frames (5m each), a total of 3h 45m, before the mount hit its safety limit.

Here it is, in all its gradient glory:

And the annotated version; there are a lot of itty bitty galaxies in Virgo!

And here is a close-up of M100 itself; what a gorgeous face-on spiral. I look forward to trying out Cassie on this target.

I think I might try a little longer exposure next. That will amortize the 90s per frame download time, and I will also end up with a smaller load of images to stack. I might even get extra photons on some of the fainter of these fuzzies. So far I have not run into a tracking problem; it’s about skyglow.

I got the Hubble Guide Star Catalog installed into Cartes du Ciel so I now in theory have stars down to 15th mag. I’m not certain that I have it set up correctly, bit there are a few more stars in-engine now.

I need to work on my plate solving workflow. Elbrus fails a lot at the beginning of the evening where I need it the most. Maybe there is something that I can configure to make this work better; longer exposures, different parameters, … More research needed.

Another gorgeous field in Virgo. Bring ‘em on.

I have avoided the Virgo Galaxies for years. The reasons are many, but chief among them is that a lot of the Virgo galaxies are elliptical, which essentially means that they look like almost nothing when you photograph them. Spirals are much more photogenic, and as should be clear if you’ve followed my target selection in this blog over the years, I’m in it for photogenic objects, not so much for a scientific exploration or any sort of “full collection” of anything.

OK, enough said. I’ve covered all that before.

M87 is a gigantic elliptical galaxy, maybe the largest object in the Virgo Cluster (?). It’s also famous because it has a jet of material coming out of its core. Hubble shot an excellent photo of this jet at one point or another. I wanted to know whether I could capture it, too.

Also, since I know that there are dozens of galaxies around the area, I wanted to start to get comfortable in Virgo, and in particular I wanted to see if I could find any spirals worth shooting over there.

So, off to M87 I went. I used Elbrus, my new “plate solving” software, to refine my GOTOs in the area. All I can say is that Elbrus is a game-changer, when it’s configured properly. That will come with time, but at the moment, every new object means I have to manually calibrate 3 nearby stars before it can do anything. Once it’s on, it’s really on.

I used my newfound information about exactly where I was pointing to pull in a small galaxy cluster that would have otherwise been off the edge of the frame to the west. Nifty!

I had the mount “bend over backwards” to pick up the target, so that I could get maximum imaging time on it. I ended up being able to shoot for nearly 4 hours before the mount hit its safety limit and stopped tracking (just like it was supposed to!).

This is M87, 43x5m subframes = 3h 35m total exposure time. I was using 5m subframes because I’m not shooting in Ha. Note that I also have a gnarly color gradient. Someday I will learn to process images better. (:

This is an annotated version of the image, showing all the other faint fuzzies I picked up — only NGC4440 is noticeably a spiral to my eye:

…and finally, here is a full-zoom crop of M87 and environs. You can clearly see the beginning of the jet going off to the right, near M87′s core. Also note that there are 2 little baby galaxies right below M87. These were not marked on either of the two star charts I used to annotate the image. Maybe I will spend some more time looking up their designations. Otherwise, they become “The Harris Galaxies”. (:

Everything worked right last night. 4026 punches out 5m subframes like it’s bored. The new safety limits are working great. The plate solving makes my heart skip when I watch it go. Even the image processing, despite ending up with a gradient, went pretty well.

I’m happy.

More Galaxy-hunting in Virgo to commence.

I had some tuning to do tonight before I could get started. That ate most of my effective imaging time.

I decided to shoot without the Ha filter, which meant going back to the FocusMax well again. That is always a chore. Eventually, I figured out that I needed a very bright star to be very well-centered, and to set the min flux setting to a nice large value (at least 1000) so that FM has an easier chance of telling the difference between star and noise.

Getting in focus took hours. Art logged on to help, and it still took from 8:30 until nearly midnight until I was ready to choose a target for the night.

What this means, of course, is that the mirror was already well on its way to fogging by the time I got started. So of my forty-five 5m subframes of M106, I think that the first dozen or so are really worth anything. Since an hour of M106 is not what I was looking for, I decided to stack all 45 anyway. That was a mistake. The image has awful gradients, and using a flat frame just made it worse. I need to shoot flats when the mirror isn’t fogged. Ditto for lights.

Anyway, here it is:

Nearly 4 hours of exposure, but I don’t think there’s anything to be done for the gradient, seeing how it’s multicolor.

Note that there are 6 galaxies in the image. M106, its nearby faint friend, a small pair just past that, the gorgeous edge-on, and another really faint one just left of that.

While the images were shooting, I started down a path that I think will turn into something really special down the road; I discovered Elbrus, a freeware(!) plate solving package. It analyzes an image, finds the stars in it, and figures out where in the sky the image was shot. Very very cool stuff. It takes some initial calibration; it has to know exactly what the image scale is in “/px, and it needs to know or discover the image rotation. Since I was having no luck having the software figure that out on its own, I needed to calibrate it manually against an image; pick 3 stars, figure out exactly which 3 stars they are, and let the software do its thing. It turns out that my image scale is a little different that I’ve been calculating; it’s exactly 1.50, not 1.62″/px. I’ll have to figure out where the discrepancy lies.

Anyway, once I was calibrated, Elbrus solved the image immediately, and was able to re-synchronize the mount so that it knew exactly where it was pointing. I can imagine a time where I can point the mount nearly anywhere in the sky, and Elbrus will take care of synching up the mount so I can get on with my evening. Not bad.

So. Now I await the sunset. Tonight, I go hunting in Virgo. I’ve avoided the local galactic neighborhood for too long.

When I got home today, I tried to process the stack that MaxIM had created of my M81 shot from last night. That didn’t go well.

So I re-stacked the subframes in DeepSkyStacker, and I’m more pleased with the results. I could probably stand to work my processing mojo some more.

Here it is.
M81, Bode’s Galaxy in Ursa Major, 30x10m subframes in Ha.

This is a center crop.

Springtime is tough for me. The local skyglow limits me to 5m subframes. In order to go “deeper”, I need to shoot through a narrowband filter. The springtime targets, galaxies, generally do not respond well to narrowband.

But, when I do shoot narrowband, I can shoot each subframe as much as I want, and the longer the better.

Last night, I was having trouble with 20m subframes, so I went back to 10m.

It occurs to me that the moon is nearly full, but for last night, 10m was too short for Ha on a galaxy. It’s still twice as long of a subframe as I could do if I was shooting broadband, however.

It’s a catch-22. But I think that really the way out of it is to restrict my subframes to 5m, broadband, and just take what I can get. It’s probably worth shooting with the C9.25, too. Once the saddle comes, I’ll mount up the long scope and start seeing how the mount can do on the springtime sky.

Another long clear night.

Since the webcam was already installed and focused, I started the evening working WCS to refine my polar alignment. Azimuth was essentially perfect. Elevation started around 200 and is now around 40. I’m done with polar alignment. The final elevation run went for a full 20 minutes, with up to 3″ of drift.

Then I had to reinstall the motor focuser and the main camera. That went fairly quickly. But I needed to do a FocusMax run, too, which is always a bit hit-or-miss. I found a spot close to focus by watching the numbers in FM. FocusMax was headed off to infinity, but it stumbled across a nice 4.78 HFD position, and I went with that.

I spent a little time trying to figure out what to shoot for the evening, and against my better judgement, I landed on UGC10822, The Draco Dwarf Galaxy. I shot 2 hours of it, 20m subframes. In order to get 20m frames, I have to shoot through the Ha filter, so this target is even less visible than it normally would be.

I have never seen the point in shooting open clusters; the photo usually looks a whole lot like empty space. But I have now found the idiot cousin of open clusters — dwarf galaxies. I swore I’d missed the object, until I looked up a photo of it online, and I then noticed the little teeny dim stars that make up the galaxy. So I “captured” it, but I am going with my better judgement and not posting the image.

By the time I’d finished on UGC10822, Cygnus had risen high enough for me to start shooting some nebulae. So I set up on NGC6820, which I’d only shot once before, and went to bed.

I woke up in the morning to a strange phenomenon; I had several subframes with trailed stars in them! Oh, the horror! I actually stacked the trailed ones into the first cut; median filtering did an OK job cleaning up the worst of it. But for the cut you see here, I only took the untrailed images, and ended up with 2 hours of data.

This is NGC6820 in Cygnus, 6x20m subframes, in Ha

Click here for a full frame version of this image.

I talked it over with Art, and he assures me that the seeing goes crazy every morning about 2 hours before sunrise, so I am not freaking out about the trailed subframes at this point. We’ll just see if this continues…

…with zero dropped subframes.

I spent a little time refining the polar alignment last night. I am still getting some drift while running unguided; I calculated it to be about 6′ from the pole now.

The guiding is even smoother now, if one could believe it possible.

I shot 20m subframes all night. I ended up with 5 frames of M51 (OK, but not worth posting). By the time M51 was finished (around 2am), Cygnus was up, and so I went and grabbed 10(!) more frames of Sh2-101.

The 3h 20m image came out pretty nice, but as always it could use some more integration time:

This is one of my standard 1500×1000 -> 900×600 crop-and-size jobs. There was a lot more context in the image, but Veronica is badly out of collimation at the moment, so there were some badly mangled stars; this is as good as I could get.

Things I noted last night:
- the pier topper needs to be rotated about 1/2″ clockwise, because the azimuth adjustment has run out of room to the west.
- Veronica needs to be recollimated. I am going to pull the long bolts and put the stock ones back in. I think I’m done with the RCC/OAG.
- I am not certain if it did anything bad, but I pulled the webcam out of the OAG and put it into the main focuser partway through the night. I would think that it doesn’t matter where in the FOV the star lies, but better safe than sorry.
- I will not be putting the mount on the tripod for tonight’s star party. I think it’s more impressive on the pier.
- One of the GOTOs last night was so accurate that I looked in the finder, couldn’t find the star, started pushing it around with the hand controller, and realized it was sitting behind the crosshairs. (:
- The mount put up more gaudy numbers; 0.4″ RMS for the night. wow.

A good night. And I got an hour more sleep and still hit a Cygnus target!

Buoyed with the success of the NJP with Pumpkin, I decided to start upping the ante. Pumpkin was mounted offset to one side, but I decided that Veronica should be balanced over the Dec axis. I was already a little concerned whether the DA’s would hold Veronica, and I wanted one less thing to worry about regarding balance. So I reworked the DA’s so they’d fit in the center of the mounting plate, and mounted up Veronica.

At the same time, I decided to mount a couple of finder dovetails on the mounting plate, so I would have a place to mount Guido. That was a measured success; it totally worked for guiding (see guide data below), but was not so cool for using Veronica’s finder; something I’ll fix presently.

Here’s the guide data. The mount is so smooth, it’s silly.

I had been having trouble last night with subframe length; skyglow was eating any images longer than 3 minutes. I wanted to test some 10m and 20m subframes, so I decided to add the Ha filter to the mix. This made focusing a challenge, although the 3-day moon did help out some by staying up late enough that I could use it as a focus target.

Getting FocusMax working again was a bit of a pain. It took about 2 hours (or 3?) before I was up and running and ready to start guiding.

The winter nebulae had set by then (it was about 11:30 or so), and the spring ones weren’t due up for hours, so I decided to run the Ha filter on the spring galaxies. M101 was the target of choice; because the polar alignment isn’t exactly perfect, my “bracketing” exposures missed the galaxy (because the GOTO was inaccurate; I need to add “re-synch on nearby star” to my workflow habit). Once I resynched, Temma put M101 on the CCD.

The bracketing exposures showed that 10m exposures were fine, but 20m are a little too long (I’ll work out later whether 15m can be done).

I had earlier figured out that I can go about 2 hours, 10 min. past Meridian before hitting the pier. I set this up in the mount safety limits, but I still need to make sure that’s actually doing something.

Because I was 30 min. before the Meridian, I set it up to run for 2.5 hours (20x10m exposures, allowing for download time), set an alarm clock, and took a nap. At 3:30a (yes, it took awhile to get started), I went out, to find that the telescope had hit the pier. It actually hit the pier during the last exposure before I got up, though, so not too bad.

I crunched the data once I woke up, and here’s what I got. I think that my data processing workflow could use some help; I stacked this using “SD Mask”, for reasons passing understanding, and got some strange diagonal noise added.

But, this is 16x10m images, 2h 40m total, of M101 in Ha through Veronica.

I re-synched the mount on a star rising in the East (Deneb), and slewed to NGC6888 to see how Veronica could do on a “real” Ha object. I set it up to run for 3 hours (18x10m), knowing that I would be up by 6:30a to turn everything off.

I went to bed, had a crazy bad dream about the mount running into the roof and somehow falling into a lake (wow), and woke up to the mount having lost the guide star because of the sunrise. I only lost one image there, too. Not bad again!

I was a little off on the GOTO again; it was 3:30 in the morning, give me a break. I only got 6 useable subframes of NGC6888; I think a cloudbank hit at some point in there.

NGC 6888, The Crescent Nebula in Cygnus, 6x10m, one hour total exposure, Ha

A reminder that the reason these are grayscale is that this is the red channel only, as the Ha filter only lets data into the red channel.

So, my impressions?
First, the NJP is absolutely destroying my circadian rhythm. I am so tired I could sleep standing up right now.

Second, the mount is so stupidly accurate that I don’t know what to do with myself. The first time I tried to cut the guiding data this morning, PemPro reported a PE curve of +/- 0.0. When I look at the raw data, other than the big jumps that happen in Dec whenever the shutter trips, all of the data falls between 0.0 and 0.4 pixels. From the previous night’s data, I had an RMS periodic error of about +0.3/-0.2, or a swing of about 0.5″. Tonight’s data looks similar. That’s a 20x improvement over the best performance I ever achieved with the G-11 (+/- 5″, 10″ peak-to-peak). NJP good? I’m sold.

Third, I think the RCC is a lost cause. It makes my telescope hard to collimate, and it doesn’t seem to do as nice of a job flattening the field as the MPCC does (take a look at the corners of the images). Now that I am using clip-in filters, and have a mount that is really guideable, I think that I’m ready to pull the RCC, get Veronica reset back to normal, and use the MPCC from here on out.

Fourth, I don’t know whether the IDAS LPS and Ha filter are not behaving properly together, or whether my optics need cleaning, or dew prevention, or image processing, or what, but these images seem a lot noisier and generally uglier than the Ha stuff I was doing last spring. I’ll get my Ha mojo back, just something to note.

Finally, I can’t wait to see what the mount can do once I’ve aligned it properly! Unguided? Crazy long focal lengths? Oh, I think we’re going to find out. Stay tuned.