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Observations of n00b amateur astronomer | Locklin on science

 3 years ago
source link: https://scottlocklin.wordpress.com/2021/08/19/observations-of-n00b-amateur-astronomer/
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I’ve been meaning to buy a telescope for about 20 years; I recently did so. Here are a few observations, most of which have nothing to do with astronomy as a hobby per-se.

The telescope:

I bought for my main gizmo an 8″ Celestron SCT Evolution, more or less because my old boss in the LBNL optical metrology lab told me to (thanks Wayne). It’s an interesting basket of compromises. The optical quality seems reasonable  and its designed to work pretty well with cheap 1.25″ eyepieces. The computer control handset thing comes default with it is …. adequate, but you have to be able to find the stars it’s interested in for alignment. This isn’t always possible in the city. The red dot sight you need to actually use this computer control is worthless and ceased to function after two days. The LED in the thing stopped working, and the “mount” the LED sat in fell apart; this is insanely bad, almost unbelievable. Begin the acquisition treadmill: telrad is pretty cool bit of Norden bombsight Americano know-how.  The StarSense handset and alignment camera is what it should come with. StarSense is a  system with a camera mounted to the optical tube, which takes pictures of random places in the sky and figures out the orientation of the telescope, and more or less how to navigate to anything you’d like.

celestron.jpg?w=720

Back in the day when I was 9 or so and planning on being an astronaut, I was a pretty good backyard astronomer; kept track of when/where the meteors and planets would be and could point out lots of interesting things in a suburban night sky. I’ve of course forgotten most of it. I also no longer live in a suburb; full on city canyon with Bortle 9 most of the time. So, even if I was as sharp as I was when I was 9, there sure ain’t many visible stars most of the time. As such, using the tracking gizmo that comes with the thing, or the extra StarSense thing for alignment isn’t cheating; it’s the only way to see much of anything.

The software for it is almost total garbage from a usability perspective. Celestron makes some wifi thing you’re supposed to connect to with a laptop or ipotato. It kinda sorta sometimes works if you don’t mind steering the scope around with non-tactile ipotato screen buttons. Ridiculously insecure and I really wish I could turn it off. For handsets, I’d pay the $400 extra for the StarSense handset even if it didn’t come with the camera which aligns to stars without you peeping through the Norden Bomb sight. Every time you turn the thing on, it forgets what time and day it is; this is a reminder to buy the $200 GPS module. Fun gotcha; it asks you the first time you turn it on where it lives, then remembers that forever; if you bork it up, it lives at Celestron HQ somewhere in California. Despite not knowing what time it is, it “knows” where it is.  This makes it impossible to align to the night sky, since you’re not actually in California. This is with the StarSense handset; with the other one you need to tell it where you live as well, and in degrees minutes seconds (as opposed to fractional degrees like on your ipotato); every time. Again, all of this is to get you to buy the $200 GPS module which I stubbornly refuse to do. At some point I’ll figure out the protocol they use to communicate and build my own for $5, which I will sell to Celestron nerds for half price.

The mount would occasionally hilariously move in 350 degree arcs West to move 10 degrees East. This came from something called “cordwrap mode.” This is one of those things that really evinces a dim view of human nature; one which is probably fully justified and why even amateur astronomers can’t have nice things. There are all kinds of serial cables festooning these machines; early on in the history of the Celestron computer mounts, people would do moron things like slew around until the cables were so tight they pulled the connectors off. So Celestron introduced cordwrap mode which carefully ensures it never rotates past some arbitrary line in its alignment which is always inconveniently near where you want to telescope around. Because people are morons, this “cordwrap mode” is not only the default: it is reset to be turned on every time you use/align the telescope. So you have to navigate some dumb unintuitive menu to turn it off,  to avoid the thing moving in 358 degree arcs to see the thing which is 2 degrees away. You also have to avoid being this stupid, which is harder than it sounds.

The other fun thing; by default it basically moves at MAXIMUM SPEED (4 degrees per second) to slew to whatever object you want to see next. Seems like that would be OK, especially if it’s taking 350 degree detours. Except MAXIMUM SPEED is also ludicrously loud. And you’re using this thing at 2 or 3 in the morning; in my case  mostly in a densely populated city with neighbors who already think I’m a lunatic for shirtless weight lifting. Navigating the stygian depths of the preposterously unintuitive menu system, you can find a place to set this to be 1.5 or 2 degrees per second where it is pretty reasonable in volume.

It’s obvious the MBAs at Celestron are selling this setup as “does everything for intermediate or well-off beginner astronomer.” But it is equally obvious that it should have been sold with the StarSense thing in the first place, or at least a red-dot thing that works. Their business model is definitely add-on sales. Otherwise it’s mostly an acceptable setup. Oh yeah; eyepieces: you get two, one of which is a useful 40mm plossl. The other one (13mm plossl) is pretty weak and I’ll give it to whoever wants it. Eyepieces are a whole ‘nuther ball of wax. Eyepieces are absurdly expensive; there exist eyepieces which cost as much as or even more than a decent telescope. They actually do make a big difference though. Some of the wider field of view eyepieces are truly huge; some weighing north of a kilogram. For contrast; the C8 is considered a medium big telescope and the optical tube assembly (OTA) only weighs 5.6kg.

From an engineering point of view, the SCT design telescope itself has some flaws. Obvious weak point: the focuser is shit and probably needs to be replaced. The mirror should also be lockable, and apparently is when you buy from other manufacturers -nothing like having your focal point change when you move the telescope around. The thing is also F/10/2000mm long in focal length, which makes it a bit difficult to point without all kinds of help. Finally if I had bought the 9.25″ scope, it would have had a better tripod (while pushing the mount to its limits). Tripod and mount are pretty important. If you screw something up here, the thing will vibrate preposterously and you won’t see anything.

c8.jpg?w=720

The online community:

Astronomy is in principle the type of community I like. Nerdy people who appreciate the wonders of the universe.  It’s a little bit like gun forums; a bunch of mostly male nerds  festooning their pointy phallic cylinders with extra expensive doodads to eke out some marginal or imaginary performance improvement. It’s also a little like wristwatch or automotive forums in that it is preposterously consumer treadmill oriented. Despite the nerdiness of the hobby, the forums have one of the absolute worst signal to noise ratios of any community I’ve ever seen. You’d think it’s pretty simple: dudes who want to see space junk. Optical physics is otherwise pretty inarguable. But the hobby is  irrational and different subsets of it have widely different goals. You have the crowd that wants to look at stuff with their eyeballs, and also the crowd that wants to use software to stitch together CCD images to “see” photos you could download a better version of on the interbutts. When you ask for advice, you have to be very specific as to which crowd you belong to, or might belong to in the future. Generally, people from the wrong crowd will also give you unhelpful advice, even when you ask them not to.

Lots of it, honestly, is upper middle class nerds counting coups by having a bigger space dong and encouraging their fellows to purchase similarly enormous collections of space dongs.  Even more hilarious: the actual things  … have dimensions kinda somewhere between astronomer and porn star.  “Hey friend, you’re not one of those 1.25″ diameter elbow cucks, join the 2” elbow crew, and enjoy spending hundreds of dollars on new glans-penis-looking tumescent eyepieces.” I have a little education in physics; what’s more; I used to actually do optical metrology, and I even have some experience in the building of optical equipment. Many of these people are speaking nonsense. There’s a lot of it in the telescope community; it’s a weird mixture of meat and potatoes optics and audioph00l tier blubbering.

Not that there is anything wrong with that, if that’s what you’re into, bro, it’s just the whole group madness of it all. Personally I’d rather spend the money on showgirls:

The astronomy nerds I’ve actually met in person are pretty cool though. You have to figure they’re posting on forums when in the throes of consumerist madness, angry at their junky telescopes, or pissed off that it’s cloudy or they live in a shitty place where they can’t see anything. Ed Ting is a fixture in the astronomy community and his sort of avuncular uncle personality is pretty common.

OK, so the community leaves something to be desired, and its an expensive consumerist treadmill. It’s still pretty cool looking at space stuff. Insanely cool, really. Globular clusters, nebulas, colorful double stars, the moon and planets are all pretty amazing even in the city. Things in the countryside are completely bonkers.

The telescope-2:

One of the things you immediately realize with this sort of thing is it’s a pain in the ass to drag something like this 100 yards away, up a hill. It’s also a pain in the ass to box it up and stick it in a car and drive somewhere with it (and then unbox it, set it up and align it); at which point you might as well book a hotel 2 hours out of the city and have properly dark skies and make a couple day trip of it. Sometimes you just want a peep at the moon which is on the other side of the building or whatnot. Hence the “grab and go” scope. Something you can stick in a backpack or bring on an airplane. Because I hate half-baked solutions, I got a little Takahashi FC-76DCU I can break down and shove in a camera bag. Takahashis are not the ne plus ultra; those are oddly enough all American scopes which you have to wait  …. years for.  Takahashis are the “future collectors item you can buy today” brand. You get a little autographed thing that tells you about the guy who made your telescope (in Japanese), and the serial number. Which in my case means “80th telescope made in  1st year of reign of glorious Emperor Naruhito.” No, really, it’s by year of the Emperor’s reign.

As with the Celestron, the mount is as important as the  telescope; in this case another Japanese thing, which I outfitted with …. timing tape to make it actually orientable. It’s not as accurate as a push-to computer mount, but it only requires I have a working cell phone to get coordinates (or a planisphere and some basic sky sense).  With a high end doodad like this you can get a really sharp focus, and while you can’t see as much as with the SCT due to less light being collected, it ain’t bad. Considering how much easier it is to move around, it’s going everywhere I go where it might be dark.

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Since I live in a city, most of the time I have a hard time looking at deep space objects, but stuff like planetary nebulas, planets, moon and globular clusters are no problemo, and are of various degrees of awesomeness.

Outside of the city though, holy shit space is awesome. We all have (hopefully) experienced night skies such as all of our ancestors have. Despite the best efforts of miscreants like Elon Musk to bomb your views with his dumb porn-transmitting satellites, it’s still pretty impressive. With a telescope it’s even more amazeballs.  Just point to a random part of the milky way with a small telescope and you’ll feel like Captain Kirk exploring the universe.

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