One step forward, ten back...

As soon as I finished he last photo, we were hit with a week of clouds. Now that they have passed, somehow I have picked up a periodic tracking error. 30 second shots are still possible, but roughly half the subs shot are trash. And what is odder, the problem that was causing this before does not seem to be to blame-so that is why there have been no new pictures this week; I'm playing Master Detective/Junior Machinist instead. All part of the game, though.

M81 & M82 remastered

Yeah, there has been an awful lot of this pair here lately...the post-processing is as much a part of learning this game as the scope is, though. Here is our pair once more, but with each galaxy exposed more evenly, and with a cleaner background. Since each object was being handled on its own, it isn't necessary to amplify the background a huge amount to bring out detail in the target objects.

Note that I tried to avoid making the background truly black...not only does that lose the faint wisps of many distant stars, it's never seemed right to me-the sky isn't black to begin with. All in all, for three months now sepnt trying to learn this art, as well as all the repair work, I am not ashamed to give myself a pat on the back for this one.

For those that care, this is a total of 491 30 second exposures (yes, over six hours.) North is to the right. (Generally, I leave North up, which would seem the obvious choice...but astro pics are most often shown with north down, since many scopes invert the image. First, I figure that any "up" or "down" is an artificial thing anyway, and second, Newtonian telescopes with a camera in the prime focus don't invert the image; that only happens when lenses are used, and there are none in my system; only mirrors. So I can put north anywhere I want it to be, just be turning the scope in the mount.) M81 seems somewhat brown and ruddy to me, but I was using the Hubble image of same as a color reference; can't argue with that. While I had some links to info about M82 a couple of weeks ago, I haven't said much about M81. In the middle of the lovely soft-looking center bulge is a black hole of over 70 billion solar masses. For such a pretty thing, it's in reality an incredibly violent place.

M81 and M82 re-revisit

The use of a baffle to hide the moonglow made all the difference. The moon was actually far brighter tonight, and still it was kept under control. This is roughly the same number of subs as the previous night.

M82 is all blown out again, but I'll have proper edits of that within a day or two, as well as better post-edits of this shot; again, I have only taken time to stretch it, and nothing else. In a rush to see what i had, I ended up stacking all subs, and some of them could definitely have been left out; I was dodging contrails much of the night.

This is just a preliminary edit of M82; I will combine the subs from the last two days to produce a more finished one. But it's easy to see that this is a weird place. I'm a bit tickled to be able to get pics of "irregular" galaxies; I've always been fascinated by them.

I've finished the overall stacks from the last two nights, and since we expect clouds for several days I'll have the chance to process each galaxy here individually, while giving the background starfield the treatment it deserves as well. I've heard some people say that exposing different parts of the picture differently is a bit of a cheat-okay, it may be. But if so, then so is using a camera to take exposures longer than our eye can manage. I'm not interested in "composites", where the components of the final picture come from other pictures, but I do think it's fine to process different parts of the frame differently. It's done with film, too; that's why there are tools like Dodge Tool and Burn Tool in Photoshop.

M81 and M82 revisit

Okay, there are some issues with this-notably the glow to the right. The moon is two days shy of full, and the floodlights were on again all night...

BUT-after all I figured out about the camera today (including the fact that light falling on the LCD screen will actually leak into a picture, and a lot of it too-Canon, that is totally unacceptable design) and using a felt "diaper" for the camera while shooting, the results are unlike anything I ever imagined I would shoot; certainly not this early in the game. The color even pretty well agrees with the Hubble shots.

This is only a quick edit; it's late, and really M81 and M82 need to be adjusted a bit differently for exposure. It's kind of blown out here, but M82 (on the left) really is showing a lot of red glow and dust lanes in its core.

All the extra work the last two weeks paid off-I shot 225 subs at 30 each, and only 2 were rejected for tracking, 2 rejected for having airliners fly through them, and 221 included in the final stack. More of this pair to come soon, once I take the time to properly edit this and do something about the moonglow.

 I can see how I need to make a baffle to keep light entering the scope tube at an angle that allows it to reflect directly into the focuser. The moon was at such an angle that I can afterward see that that was happening. The inside of the scope is just flat black spray paint, and actually that is not nearly flat or black enough, so keeping stray light out will be on the list of future projects-out of the scope as well as out of the camera.

Why "stack" frames?

This is a single 30 second exposure from the set of 45 that went into the pictures in the last post, brightened to the point that the core of the galaxy is as bright as it is in the final stack. Notice that there is nearly zero difference between the brightness of the galaxy itself, and the sky.

In these conditions, the long exposures used for faint objects just won't help; the sky keeps getting exposed just as much as the target. Stacking, or adding a lot of short exposures, is not quite the same as having a long exposure. Instead, it keeps track of which pixels are the same in each shot, and which are different-the ones that are different are considered "noise" and ignored (or replaced with something-usually an average of all the pictures' color at that particular pixel.) So the final picture may be just as faint as a single short exposure, but when you brighten it a lot, like with this photo, the background noise has been reduced enough so that the sky still looks black.

In a nutshell, longer exposures capture more light from the target, which makes the target brighter. (That's the traditional way when film was used.) Stacking improves the ratio of picture to noise, so you are able to "amplify" the picture, so to speak, without drowning in the noise. The best photos use both; with shorter exposures, it's possible that some actual photons from the target are being tossed out as noise. So I still want to get to where I am shooting a minimum of 60 seconds per sub, and as much as 180. But there are times, like last night, that the ambient light prevents that, and that is when it is nice to rely on stacking alone to help draw those faint things out of the slop.

M101, the Moon, and the Viewfinder

So probably not the best choice of targets on a very wet night with a nearly full moon nearby, I admit. M101 is a huge object in the sky, but with a very low brightness. But it was there, and nothing else was really within reach with the moon where it was and my scope set up where it was. But I did learn a few things, or at least remember things that I have known for years and had set aside while I worked on other problems.

I took two short sets, since I had to execute a meridian flip after a short time. Of course, I unthinkingly flipped my camera over as well, and halfway through the motion realized that my flat frames would now be useless. But for some reason, while trying to set it back in the original position, I noticed that I had the camera set for Automatic White Balance. Now, normally, that is okay, but when shooting regular pictures, I NEVER use that setting-I always choose the proper white balance for where I am. And it seems that I've had it on AWB since I started shooting with the scope.

Now, even without light pollution, the sky is not truly black, but a ruddy brown. The AWB will try and compensate for that, and all of my galaxies have been very blue. I had assumed that that was largely due to the stretching in Photoshop, which does shift color. But with the white balance restored to the proper setting, compare the tone of these two pics-the first is blue, the second is proper.

In the second picture, a mysterious enemy has shown up again. A few weeks back, I had several sets come out with that odd vertical banding. Since it then went away, I was assuming it was an artifact from one of my reference frames. But it showed up again in the second half of the shoot. The galaxy could actually brighter in this pic, but the bands were just too dominant then.

My main suspect is light leak-especially with such a bright moon, I should have also have remembered this fact about SLR cameras. It's a small and subtle flaw, small enough that for normal uses, photographers can get away with ignoring it completely. But during long exposures, light coming in the viewfinder can actually bounce around the raised mirror and hit the film or sensor. The shots I did last night with the moon at my back were simply beautifully lit, just not the light I was after. I suspect these bands will have a similar cause. Sometimes, I will shoot my dark frames while I am putting everything away, and the scope will be sitting near the door with it's it's cover on. Sometimes I remove the camera, and shoot the darks with a body cap in place. But I will usually have some light turned on then to help me break down. I am guessing now that if I toss a piece of black fabric over the camera the problem will go away. I'll probably intentionally pollute some test frames as well just to see what that looks like.

No big copies of these pics; the session was short, and too few photons were collected. I stacked these with my earlier shots of M101, but the end result was honestly no longer acceptable to me; the color balance is too awful. So no great photographs, but a step forward, repairing my brain rather than my equipment this time.

M13 Globular Cluster in Hercules

These are the first actual subs worth keeping that I have taken with the new setup. I still have a lot of work to do fine tuning the rig, but this isn't too bad. On the other hand, I only used about 2/3 of the frames i shot for the stack.

M13 is made up of perhaps half a million stars, and like most globular clusters, is orbiting around the center of the Milky Way galaxy. It's a pretty spectacular sight-the area visible in this picture is about 2/3 the size of the full moon, and in dark skies can even be seen with the naked eye, if only just.This image has some pretty blobby stars, but it was borderline foggy conditions...visually, I couldn't make out a single star in the constellation containing this cluster. This is just a baseline to add future exposures to, and a test of some of the mods I've been making to my scope setup. Given the nature of the skies, I didn't even spend much time with PhotoShop trying to clarify this picture, beyond some iffy contrast enhancement, since the background was really not black at all in the master photo, but reddish gray due to the normal light pollution and the moon.

M13 was discovered by  Edmund Halley in 1714, and Messier added it to his catalog half a century later. You can imagine how this could have been mistaken for a comet. The globular clusters especially were of a concern to those early comet-obsessed astronomers, since they are perfectly identical to actual comets in all ways save two-they don't move, and they are actually miniature galaxies on their own, not just balls of ice and dirt. Messier, by the way, said that M13 was entirely nebulous, with no discernible stars...again, it shows just what they were able to learn and deduce with equipment much worse than what I have today.

Because their close proximity has drawn all the material together in the region, any dust and gas clouds were long ago turned into stars in the most globular clusters, so they generally have few if any younger stars. Indeed, most of them are full of stars that are even older than the Milky Way itself-as much as ten billion years old.

Back in 2007, during a brief period when I first tried to get some photos with my scope, this was the best image I got of M13. Actually, it's probably the best image I got of ANYTHING that year, and it shows just why I gave it up as a bad cause.  Of course, few things show the weakness in an astrophotography setup the way clusters do-they are made up entirely of point sources of light, and even the tiniest errors are obvious. The gaseous nebulae can still look beautiful even with some tracking problems-look back to my early Orion shots as an example.

The new gear

I haven't had any new photos to show for some days-I've been busy playing telescope mechanic.

When you want to upgrade equipment like I own, any telescope store will simply tell you that you must start over with new shiny (and expensive) equipment, since your inferior junk is simply not worth upgrading, or worse-is totally incompatible with "real" equipment.

This may be true if you aren't sure which end of a drill you're supposed to hold, but there is no reason you can't sigfinicantly improve the stuff yourself.

My tripod was horribly wobbly-the slightest touch to it or the scope (the kind of thing you would do if you tried to use it, for example,) would take 30 or 40 seconds to dampen itself out. Additionally, it was flexible enough that I could watch it deflect from side to side as the scope moved-well over half an inch. I went to some pretty funny lenghts to stabilize it, but a dog is a dog. A new tripod was needed. Well, firstly, it is true that my EQ mount will not bolt directly onto anything out there as is. So I went looking for the type used with many Alt-azimuth mounts, which have a large flat plate on top. New, something of adequate strength was upwards of $300, and that still would require modification. A local store has a back room full of used equipment, and by chance they had four suitable tripods, all alike. They wanted $40. But one of them had a broken clamp for adjusting the length of the leg-I pointed out that they'd only ever sell that one if they had sold virtually every other tripod in the store first. They gave it to me for ten bucks, and I replaced the clamp with one from a speaker stand. Now on to modding it to take my mount-

This was fairly simple...if my old mount and tripod MUST go together, then just pull the top off of the old tripod and bolt it to the new one. The first night I tried this, I found I had to fiddle with my method a bit, but that was easily fixed. (See that freaky streaky thing two posts back...) And walla! as they say in Yurp...the tripod is now replaced, for a total cost of $10, since the speaker stand was already missing other parts anyway. I can sit on this thing and bounce around with no wiggle or wobble at all. I have an ETX-60 that I'll probably mount on the old tripod.

Ages ago, the motor driving the declination axis died, and in this case it WAS true-an exact replacement simply didn't exist. But a motor from a scope sold by Orion turns out to have the same dimensions and motor speed, just a different set of reduction gears. That sells for $59 all over the internet...too high. At this same shop, some of the "used" stuff is actually new replacement parts that they no longer want to stock, and wouldn't you know, there was that Orion motor. That plus several of the clutches that I mentioned earlier were $15. (The clutch is that shaft with the chrome locknut and brass gear at left.) It did take some fiddling and drilling to adapt the gears from my old broken motor to fit, but in the end, it all worked. I hadn't realized how much I missed having this-a motor on this axis is not needed for following objects across the sky, but it makes it MUCH easier to aim and fine-tune. And yes, for you sharp-eyed viewers-the chrome thing on the left is indeed a Ludwig Hi-Hat clutch, now holding the bushings for the worm gear rather than holding cymbals on a drum set. It's getting harder and harder to decide what brand this thing is.

I wish I had though to take a picture of the old electrics-it was a horrorshow. The handset had two telephone lines plus a battery pack hanging from it, which over the years had suffered from various cable wraps and zip ties and tangles. Each cord ran to a different part of the rig, and things were always a mess.

After working all the rust out of the handset, I replaced all the wiring-the handset now connects to a computer monitor cable, which leads to a junction box that lives under the tripod. That has the cords that run to the motors, as well as a plug to use either a battery pack or an AC adapter.

Here's the finished rig-the handset can be stuck to any tripod leg with velcro, while the main electrical guts are on a box that straps inside one tripod leg. All very tidy, and so much less to trip over. I've added a steel rod from the scope mounting rail to the counterweight bar as well, to fight vibration. There is no detectable movement in any part of the mount or tripod as the scope is slewed through its entire range of motion. Which means two things-it's a much better platform for taking photos, and if there are still tracking issues and star trails, I can't blame anyone or anything but myself.

Today I have taken it all apart again to repaint a lot of the metal bits with Hammerite; this is going to be one very pretty kitty once that is done. Then I'll have to ruin that sleek look with some bands of bright yellow duct tape around the legs. Ugly, but I know I'm going to trip on them constantly if they stay black. Or I might add a red LED to the junction box.

Over the next couple of weeks, I should be able to show whether this makes for better pictures or not...

Some Terminology

I was asked about some of the words I've been tossing about, which were not usderstood by all the people reading. Try and remember, by using lingo I am only trying to appear smarter. Here are a few definitions.

Mount-the mechanical pile of stuff that is connected to the telescope, which allows it to point in different directions. It includes (in my case) the motors needed to keep the scope pointed at the same place in the sky while the Earth turns.

Tripod-well, the tripod. The mount attaches to the top of it. While often sold together, they are unrelated, and have their own demands for quality.

Clock drive-those motors can move the scope around at different speeds and directions (moving the scope from target to target is called slewing) but originally, all a motor did was to move the scope with the Earth's rotation (actually opposite that), and that is called tracking. They were given the name of Clock Drive many years before people were even using electric motors; being spring-driven, they were, in every way, clocks. With modern stuff, one set of motors is used for both needs-tracking objects, and slewing. When tracking, the mechanism can still be called a clock drive.

Subs-each photograph I take is actually made up of a lot of shorter photographs. If a faint galaxy would need an exposure of 30 minutes (meaning, leaving the "film" exposed to it for 30 minutes) I would likely take 60 30-second pictures, which are added together. Each individual exposure, or click of the camera, is called a sub. When I stay aimed at one object shooting a lot of subs, that is called a set. Sets are then stacked to produce my final photos.

And just how important is a clock drive? Many telescopes are sold without them, even these days, and even some pretty big scopes. Well, the Earth takes 24 hours to rotate the 360 degrees of one circle. That works out to one degree of rotation every four minutes. The full Moon is almost exactly one half of a degree across. Which means, if you focus a scope on the moon, in two minutes it will be completely off center in two minutes. The bottom line is that even a wide-angle scope like mine can only take a picture for about 3 seconds without a clock drive; after that, the stars are stripes, not dots. Most of my short astrophotography career has been learning how to align the various gears and axes of the mount to allow longer exposures. Those big scopes sold with no clock drive are definitely not to be used for photography. (Usually they are a close relative to my scope, called a Dobsonian. A Dob is not actually a type of telescope, just a type of mount for one.)

Hope that makes it clearer. And please, if I say something you don't understand, ask about it-that's why this blog is here. This isn't supposed to be an astronomy textbook-I'm just going to write about what I'm doing, mostly for fun, so without questions, I won't know what other info is important.

New equipment

Over the last few days, I managed to get my hands on a massive new tripod, an new motor for my declination axis (haven't had one in years) and a handful of drive clutches that were actually machined by someone who CARED.  We had a little star party Saturday night, but while a lot of fun was had by all, I broke a basic rule of any science/engineering/mechanical project. A wise person will only change one thing at a time when experimenting. But me-wise? HAH! I laugh at wisdom. I started the night like this-

1. A new tripod,
2. An untested and improvised means of attaching my mount to it,
3. A new motor in a place where for years I have only had hand controls,
4. freshly-designed, cut, and untested mounting hardware for that motor,
5. A location I was not familiar with,
6. Friends around rather than doing all of this alone like usual.
7. There may have been some single malt whisky involved
8. My hand controller (which runs all of those motors) Started randomly changing its mind about which hemisphere we're in.

In addition, I still hadn't had a night shooting with the improved parts mentioned below. So a LOT of variables were being dealt with at once.

The result is that when I encountered problems, there were FAR too many things to track down...which led to some truly hilarious results, as well as one of the most astonishing astronomical images ever created-

 I doubt I will ever be able to equal this incredible achievement.





In time, I finally figured out what was wrong, but was running out of night. So when I finally started shooting, I ended up making mistakes that made most of the night's pictures useless (but well-tracked-yay!). In the next few days, I'll properly sort out the entire new setup, and the difference should be considerable from what I was working with before. Scott shot a LONG set of subs of M13, while Mark was getting video of Saturn that should be stackable into something pretty special; I'm looking forward to seeing their results for the night.

Algoreb in Corvus

This is the star Algoreb, in the constellation Corvus. The only notable thing about this photo is that it is a 60 second exposure, and until tonight, I could not shoot pictures with such heady exposure times. However, it has a passing interest outside my own struggle to make my telescope work. Algoreb is a lovely double star (even in the smallest scopes, they are noticeably different colors), and the smaller partner, Algoreb B, is extremely bright in infrared. It's still cloaked in the gas cloud from which it formed, which it is heating up a lot; and is therefore very young. The two stars are actually very far apart, and form a "visual binary" pair; they actually have nothing to do with one another.

The name Algoreb has been applied to another star in the same constellation in the past. But the really interesting thing about this pair is that they represent one of the few things left in our world that you can't quickly learn about on the internet. Efforts to Google it give you a lot of information about Al Gore, but almost nothing about this star.

Bingo

Finally, the primary part that has caused me so much woe was found...the shaft with the worm gear that drives the RA clock (okay, the one that cancels the Earth's rotation) has a piece attached to the end, secured by a set screw, with a gear which is in turn driven by an electric motor. The hole in that piece, which is placed over the aforementioned shaft, was not drilled axially to the gear teeth. Put another way, it's really crooked. As in, it looks like someone hand-drilled the bloody thing.  What those gauges are saying is that the error was over 100 thousandths of an inch, just one inch from the bearing holding the part. Cavemen used to be better machinists.

How I managed to miss it was by going over all these parts singly, when I should have been looking at groups of parts together. Granted, for a part with obvious marks from being machined all over it, I can forgive myself for thinking the inside was made the same way.

So anyway; the hole was enlarged enough for the part to fit axially, and I added three set screws to not only take up the slop but allow some adjustment later if needed.

The weather was mostly cloudy, so I didn't get to test it hard....but I was able to get some star trails five minutes long with the mount intentionally out of place, and they were straight lines. Before, they had a v-shaped jog every 110 seconds or so. I did a quick and dirty polar alignment, and got a bunch of 120 second frames with no drift. So the 30 second restriction is lifted. Of course, with my old camera, 30 seconds is the limit of what I can shoot without manually exposing each frame; and with a light-polluted sky, it's not always good to shoot longer than that. But now I have options, and I won't have to toss a third of the frames I shoot. This was the last major step in transforming this old pile into a useful photography tool. Not a great one, but good enough for me to spend a lot more time learning with.

A closing thought? How about this-in all the years I've collected little bits and sticks and clamps and cute fancy magnets so that I can get a dial gauge to sit exactly where I want it, I suppose I never actually needed it on something made entirely of aluminum and brass. I spent more time finding a way to attach the gauge then I spent fixing the part. The moral being, you should ALWAYS get that extra tool, even if you aren't sure how you'd ever use it-you never know.

M81 & M82

Here is a quick stack of my first shots of M81, Bode's Galaxy, and M82, the Cigar Galaxy in Ursa Major. M82, on the left, is a bit blown-out in appearance, since I was trying to bring out the spiral arms in M81. With more subs added, these two can show a great deal more detail; they're pretty large in appearance compared to most galaxies, and pretty bright. M82 is also blazing...this image from Hubble shows a huge amount of energy in near-infrared, but the actual infrared (heat) pictures from the Spitzer telescope are astonishing. This is one hot place right now! The x-ray images from Chandra are also pretty remarkable. By the way, in the Spitzer image, the vast clouds of red gas are made of polycyclic aromatic hydrocarbon. People in large cities know the stuff well-they called it smog. Since all of that heat is in the infrared range, it is not visible to our eyes-or my camera, which (not surprisingly) is designed to only show stuff we can see ourselves.

These two galaxies are inextricably linked-M82 is responsible for the formation of the spiral arms in M81, while M81 has caused the massive amounts of star formation in M82. Eventually, the two will merge into one galaxy.

I'll post better pics of both soon, once I can edit the picture for each individual galaxy. But really, I can't wait for a night of good dry still air to shoot these two again...it was supposed to be stormy tonight, and while it was clear, it was very turbulent; hence the big fat stars. Lots of room for improvement here, even at my current skill level, but I'm still proud of the shot-M81 is such a pretty galaxy, and this is the nicest picture of a spiral that I have taken so far, I think.

Why do so many of the things I photograph have an "M" in their name?

Scott called me out on my disparaging remarks about certain objects in the Messier catalog, and a couple of younger readers aren't sure what we are talking about. So here's a teeny bit of history. I promise it won't hurt, even though it involves French people.

Astronomy a few hundred years ago was a very different science than it is today. For 2000 years, people had studied the sky, but for reasons that were turning out to be pointless. Then along comes the telescope, and in the early 1600s, shows that really everything we knew was wrong anyway. By the end of that century, most of the resistance to new ideas in science was going away, and astronomy was ripe for being re-invented as a new science.

The catch was, "science" as we think of it now was also just being invented...or at least the ideas that mathematical models could be compared against actual empirical studies, and the results used to check each other. The lads who started the Royal Society were in no small part for eventually deciding on just what "science" and the "scientific method" were, all around this time. But in Europe, Universities and States didn't really see any reason to fund "research" and other messy things like that, and since it could often be expensive-and dangerous-it fell to rich guys with not much work to do to start the ball rolling. Being one of the Gentry provided plenty of money for stuff, and the inbreeding that went with it no doubt helped with doing the dangerous parts.

So early "modern astronomy" really got rolling in the early 18th century, and most of the work was done by people who were experts in other fields, who could simply afford to build a telescope. Many of them were great names in science, but generally not for their work in astronomy; we tend to remember them for things that actually took only a small part of their time. Edmund Halley was a geologist and mathematician; today we remember him just for making an almost offhand prediction about a comet that had popped around a few times before, for one example.

In fact, what a lot of these guys were into was comets. There were no major sky catalogs yet, and making one was certainly too much work for someone who had other real work to do...but those comets, man, those were really exciting. The skies were essentially unchanging after all, or at least predictable once Newton's (mathematical) model of where to look for planets was borne out. So there was little need to study it, it was felt. But comets-they broke the rules-they showed up randomly, they changed their shape and appearance, etc. Plus, you could get some real nice pats on the back from fellow philosophers (as scientists were called then) by finding one first.

So, now we have a bevy of well-heeled smart fellows scanning the skies for comets. When a comet is far away, it looks like a slightly fuzzy star. As it grows closer, it gets fuzzier. So they looked for fuzzy stuff. And found a lot of fuzzy things that were NOT comets-they stayed in the same place. And different guys were spending time discovering the SAME non-comets.

Charles Messier, in France,after much work, published his first list of Messier Objects in 1771. He did not discover all of the items in the list; he was a compiler. Over the centuries, others have added to his original list, since there are letters and such that show he had been told of other items as well, but after 100 or so items he seems to have lost some interest. The last couple of items in his list were actually added in the 1940s. The list is not particularly well-ordered, it often skips around the sky in a charming manner, and even skips some items right next to others that were included (such as in the Leo Triplet of galaxies; NGC 3628 is certainly visible to anyone who could see M65 and M66.)

The singular purpose of this list of  this list was to allow the astronomer at his telescope the ability to determine if that faint splodge was something new, or something he could ignore. It was a handy thing. It was a list of items that were nebulous, or cloudy...things that could not be focused sharply, since that was what the comet hunters were searching for.

The notion of "science" was certainly developing in the century that followed, and in the 1880s a new catalog of celestial items was created, called the New General Catalog. It included all of the Messier objects, so those all have an NGC number in addition to their Messier number. It's intention was to be a proper catalog of celestial objects, rather than a helpful guide for just one type of stargazer. Other catalogs have been made since, but those first two, the Messier and New General Catalog, contain basically everything that can be found by casual backyard telescopists. In truth, most of us, myself included, have much better telescopes than what was round during Messier's day...several of the Messier objects are very obviously just a handful of stars to us, and it's hard to imagine them being seen as nebulous at all.

One sort of object like that is called an open cluster-from a few dozen to a few hundred stars, clumped loosely together, and with binoculars especially they can be very beautiful. Many can be seen by eye from a nice dark spot. I tend to skip them when using my scope, since they often make for a pretty boring photo. Not always, of course, and some of the open clusters are pretty things indeed.But to answer the original questions, the items in the Messier Catalog are all good targets for scopes of the sizes people tend to have in their backyards, between 4" and 12" of aperture. So many of the things I will post pictures of are called "Mxx".

Ironically, as far back as 1654, an Italian astronomer named Giovanni Battista Hodierna had compiled a list of objects that could be confused for comets, more than a century before Messier. As often happens in the history of science, it was totally ignored.

M46 & NGC 2438

When most kids' teachers were sending home notes to the the parents saying, "he's got plenty of brains, but just won't apply himself," my teachers were saying, "he likes the astronomy sections, but he just doesn't care enough about open clusters." I've carried this stigma my entire life.

However, as Scott has pointed out, open cluster M46 comes with a truly cracker-jack prize inside-NGC 2438, yet another of those stars like our own that has decided that enough is enough. This is a VERY early set of subs, and most of the stars in the cluster really aren't even visible, but I'm a sucker for those lovely little blue splotches. Indeed; they are some of the few objects that look similar in a camera AND an eyepiece. So I'll try and grab some more subs of M46 before it's too late in the year; it's already setting pretty close to dusk as it is. There is another Messier object just one degree to the west of this one, M47...but seriously, who gets excited about 17 stars in a single field of view? I mean, I could have taken a photo if I'd felt like it. But I was getting ready to shoot a fresh set of subs of a proper target, M101. So I spent 45 minutes getting the focus exactly right, shooting my flat frames, really fine-tuning the position of the counterweights...when in a 2 minute period, the entire sky clouded over. And it now looks like we'll have heavy clouds and rain for a few days. And ya know what? I still don't feel bad about skipping those shots of M47. Bloody open clusters.

In my defense, I might point out that while the exact distances aren't really known, NGC 2438 has a different angular velocity from M46, and therefore isn't really a part of that cluster anyway...

Camera Layout guides

One of the lessons I have learned the hard way (by taking several nights worth of M42 pictures that I cannot use together) is that you need to plan ahead when framing your shots. At first, when I wanted a short exposure of the bright center of the Orion Nebula, I naturally centered that bit in the frame-after all, the quality of the image is greatest there. But later, when I started to collect longer exposures, I found that the object was so much larger that I cut half of it off.

Now the pictures I did take that aren't aligned-there are other ways I can combine parts of them, but I cannot process them together in DeepSkyStacker in the most beneficial way. A few days ago I mentioned that I'm now including a snapshot of the camera position with each set of subs. Well, here's the other habit I'm getting myself into-I put my camera into Starry Night Pro (my digital star map of choice) as an eyepiece, and can have it project that field of view over an object. This image is now stored in my M42 directory, and I can refer to this each time I set up to shoot it.

If only I could have the same rectangle built in to the reticle in my finderscope as well-that could save ages in starhopping to a target.

M95 & M96

One step forward, two back...as mentioned before, there were no usable reference frames for this, and most of the subs in this set were tossed out anyway.

On the right is M95, and you can just make out that it is a barred spiral. M96 is on the left, with its outer arms just out of reach. A lot of "not quite" in this set.

The shapes of the stars near the edges show a typical fault with Newtonian scopes, called coma.  Not much can be done about it, provided that the distortion is axial-meaning that it points to the middle of the field of view. Well, there IS one solution, invented by Bernhard Schmidt in 1930-it's called a Schmidt telescope, which is essentially a Newtonian with a corrector plate, or eyeglasses. These days, Schmidt-Newtonians are very rare, since Newts still have this great huge tube, where the reflector is at the back end, and the focus (and eyepiece) is at the top. More often now, the light path is bounced of yet another mirror back through a hole in the primary, so that the eyepiece is at the back of the scope, where one would expect. This halves the length of the tube, also. That is referred to as the Cassegrain focus, named for Laurent Cassegrain, who published its design in 1672. (Today, it's pronounced Kass-a-grain, which of course is nothing at all like poor Laurent would have said it. At least Schmidt's name sounds more-or-less as it should.) Combine one of these scopes with a corrector plate, and you get a Schmidt-Cassegrain, which is really a much better instrument for deep-sky photography, but they cost several times what a Newt of equal light-gathering ability does.

All of this information is to detract from the fact that there just isn't much to say about the photo here.

M105 and neighbors

On the right is M105, a giant eliptical galaxy with a massive black hole in the center. With an 8" telescope in my back yard, you can't see the spiffy X-Ray jets the black hole is shooting tens of thousands of light years, unfortunately. On the other hand, if we could see them with an 8" scope in my back yard, that might not be so good either.

On its upper left is another eliptical, NGC 3384, and the cute little spiral to the left is NGC 3373, also known as NGC 3389. No doubt there is an interesting story about who is still arguing over which object goes with which catalog entry (indeed, even at least one Messier object is still debated after more than 200 years), but I don't know it, And I don't feel like finding out right now anyway.

All three of these galaxies lie right under Leo's belly, just above M95 and M96, and are part of the M96 group, also called the Leo I Group. The whole lot of them are just a few degrees away from the Leo Triplets that I posted pictures of earlier. I can't quite fit these in the same frame as M95 and M96. I did shoot those a couple of nights ago, but managed to somehow ruin the images. (I've been pretty sick for about a week; I set up the scope a couple of times, then dressed up like an Eskimo and went to sleep looking at the stars. I also tried to process the images while feeling pretty bad-and deleted all the reference frames.) I may or may not post them later. In larger scopes, you can start to see that many of the stars around these three are in turn galaxies as well; it's a remarkable area...but in a month or so, Virgo will be in prime shooting range, and the galaxy fields there put all else to shame.

Last night I also got my final set of 4-second subs of the Trapezium in Orion; it's too late in the year to re-shoot the longer exposures I did a couple of months ago with more useful alignments. The main problem was that I failed to allow for the actual size of what my little scope would capture, and half the nebula is cut off, like the way bad photographers cut people's foreheads off. Well, I'll be ready next winter, at any rate, and at least I have a well-framed set to start building the project on next year. The Orion Nebula and the Eta Carina Nebula are two that are so bright and large that they can only really be shown in composite pictures.

A quick thank you

Rather to my surprise,there ARE a few people subscribing to this. (Hi, Liv!) Honestly, I know it isn't the overwhelming quality of my images, but rather the fact that there is so much in the sky that is utterly breathtaking if not mind-blowing, and all of it is just beyond the reach of our eyes. I hope that people see that my reason for doing it was that I had to simply tell someone-anyone-how excited I am at finally getting that extra little boost in vision that lets me get a glimpse for myself. It's one thing to look at and admire professional images, but I never feel connected to them; they are abstract and unknowable, no matter how awe-inspiring. But somehow, seeing the same objects with my own eyes, even if I have to use some eye-enhancing tricks like storing photons with a camera, those objects are now part of MY universe, and I am part of theirs. After that, the professional pictures gain some reality as well.

So if you have subscribed, it is you doing me a service, not the other way around-I get to tell someone about the exciting things I see, which is as important as seeing them.

And if you have never actually looked through a scope before, then NOW is the time...Saturn is in prime viewing position right now, and for a "first object" nothing is better. Sure, you may know what it's rings look like, but when you actually SEE them...the sky changes forever, and you become part of the universe, not just part of the flat skin of one little rock.

If you don't have access to a scope or someone with one, email me with your location and I will find an astronomy club holding a star party near you-a large part of any astro club meeting is giving people their first looks.

M97 & M108, reprocessed

M97, the Owl Nebula. The same shots I took a month ago, but processed a little bit better this time. The original post is here.

 And M108. From the same shot at M97 above (they are quite close to each other). The link above shows my first effort at post-processing this image. I think this one may have gone too far the other way.

M68 Globular Cluster

M68, also known as NGC 4590, is a globular cluster in Hydra. Most globulars are miniature galaxies themselves, orbiting around the center of the Milky Way. This one is about 33,000 light years away, and is another binocular object from a dark spot. I was a bit hurried when I shot this; it's only about 10 frames, and the focus is pretty poor. I had just focused with a Bahtinov mask, so I suspect the real reason is plain old bad seeing.

"Seeing" refers to the stillness of the air, especially up high. Good seeing means less star twinkle and smaller star images in photos; bad seeing makes stars twinkle beautifully, but makes them big ugly blobs on photos. Large blurry items like nebula are not that badly affected by bad seeing, but star clusters are especially, and it's not the sort of problem that software can really correct. I can "shrink" each star with Photoshop, but that is really just throwing away data; many faint stars are lost in the process. Plus, I don't look to Photoshop to fake pictures, just to enhance the information already present in the picture.

NGC 3242, The Ghost of Jupiter Planetary Nebula

Located in Hydra, just barely high enough for me to grab about 20 minutes worth of photons before it dips below my roofline.

This is the remains of a star pretty similar to our own-once they burn up their fuel, they become red giants, and blow away most of their mass in these lovely shells of gas lit from within, this one by a white dwarf star that is all that remains of the original. In spite of its name, it's about half the apparent size of Jupiter, and totally unlike it in color. It is called the Eye Nebula often, but that too is confusing, as the name is also used elsewhere. You can catch this with binoculars in a dark sky, which is not bad considering that it's 1,400 light years away.