rickwayne

My wife was also rather amused by the "can be an expensive hobby", I should note.

On 27/11/2019 at 16:53, Andy R said:

as for the camera, we all got to start somewhere and the 1100d is good enough    . It can be an expensive hobby thou  

<falls off chair, laughing hysterically, gropes frantically for asthma inhaler>

On 27/11/2019 at 16:53, Andy R said:

 

Hi, and welcome!

In order to recommend a camera it's important to know what kind of work you want to do, and how "Hubble-like" you want your pictures to be. For example, if you want to get detailed pictures of small (far-away) galaxies, or images of faint deep-sky nebulae, you're probably going to be disappointed, that's technically rather demanding and probably will require fancier equipment.

But if you want to snap some shots of bright planets, the Moon, or some bright star clusters like the Hercules, there are a couple of things you can do. The simplest is just to search for a cell phone mounting bracket that you can affix to your scope; there are bunches of them available and I'm no expert!

You can possibly mount your Canon DSLR on the scope, with no lens or eyepiece, to do so-called "prime focus" photography. The issue here is whether you can get the camera to focus. You can find out whether it's possible by:

1. In daylight, aim your scope at some distant object (NOT THE SUN!!!).
2. Remove the eyepiece, and turn the focus knob "inward" so the focusing tube is as little extended as possible.
3. Remove the lens from your DSLR, and turn it on. (Be careful about dust!) Turn on Live View.
4. Without banging the focusing tube of the scope into the delicate bits inside your camera body, hold the camera up to where the eyepiece would go.

Can you see an image on the camera screen? Can you move the camera close enough that the image becomes sharp?

If so and there's enough room to spare, you can buy a T-mount adapter that will mount on your body, and a T-mount-to-1.25" adapter that screws into that and lets you plug the camera into the scope in place of your eyepiece. You could start here (no recommendation implied, just the first thing that came up when I searched).

You can also find adapters that offer the option of "eyepiece projection", which allows you to do more or less the same thing with an eyepiece in place. While this will work mechanically, the results optically are likely to be not so great.

Good luck!

MarsG76: Right? The "welcome to the dark side" comment was also apposite. Where "dark side" is "black hole of time and money that you will wallow in happily".

Nice work, I'm totally jealous of the NA Neb shot as your first. Heck, focus wasn't even THAT bad! I find that it's like Andromeda -- an easy "beginner" target that's nonetheless an endless chase after "I can do it better. And better. And better still."

One of the issues with it is the overwhelming richness of the star field. It is of course an artistic choice, but you could consider using starnet++ or something similar to remove the stars from your image, wonk on the nebulosity to your heart's content, then blend the (unwonked, or even toned-down) stars back in after.

And you hardly needed to characterize yourself as a visual astronomer. Only visual guys are persnickety enough to call it the "North America" Nebula instead of the "North AmericaN" nebula!

<Ducks hail of tomatoes and other kitchen scraps from other imagers, grinning>

Ain't APP a sweetie? I am in fact waiting for it to chew up a few nights' frames of the Elephant's Trunk as I type.

Heck I think I'm gonna watch it again right now 🙂

Have you watched Dr. Glover's talk? Made it pretty clear to me. 

Amazing job controlling the dynamic range there.

Re narrowband on the cheap: You can start without a filter wheel, and with a single filter (H-alpha is the obvious choice). I never thought I'd say this before I tried it, but black and white imaging can be really satisfying too. So e.g. a 183MM Pro can be had brand-new for £780, and used filters are widely available. It is truly incredible what's still possible even city skies with narrowband. This is two filters, not one, but was shot in the brightly-lit parking lot of a dog park near my house! And unguided, at that. APOD? No. Amazing to me? Absolutely.

(Edited to add) And this one, while shot at a darker site, gives you an idea of the rich tonality that's accessible to monochrome narrowbanders.

 

The North America (pedant note: no final "n"!) and Pelican are lovely together, but depending on your framing you can get a great image of this nice bright nebulosity no matter what. Since the area is so rich in Ha, I'd go modded and not too long a focal length.

This was serendipitous, just kinda "what I wound up with": https://rickwayne.zenfolio.com/astrophotos/hcdfeee75#hcdfeee75

One thing that you'll hear recommended in almost every one of these threads is to buy one of the good books on the subject. Making Every Photon Count is a forum favorite; since I'm a deep-sky guy, I'm all about The Deep-Sky Astrophotography Imaging Primer.

We all have holes in our knowledge but these books are really good at helping one discover that they don't know what they don't know! For example, many folks want to buy kit they can use for planets as well as galaxies and nebulae but planetary and deep-sky are so different, about the only point of commonality is that they both involve swearing at cameras in the dark.

Best of luck, and joy in the journey!

APP is Astro Pixel Processor. Not as many features as PixInsight but pretty straightforward to learn and use. Gives IMO excellent results. Reputedly one of the very best packages for stitching mosaics.

I'm particularly fond of your Pleiades, myself. Ain't that APP a grand little program?

Don't neglect consideration of KStars/Ekos for automated acquisition. Very full-featured, runs on a Pi, Mac, Windows, or Linux, is open source, built from the ground up for remote operation, sequences and automates dome control, heaters, park/unpark, meridian flip, guiding, mosaics, more.

Likewise The Forum That Dare Not Speak Its Name* has plenty of downloadable data in the Beginning And Intermediate Imaging forum.

*Cloudy Nights. Shhhh!

This is a case of "easy to learn" vs. "best results". At that focal length you will likely eventually get smaller RMS numbers with OAG but a small guidescope, rigidly mounted, will likely get you guiding more easily. You can probably reuse the camera for the OAG so the only sunk cost is the guidescope, which you can resell for half or better.

Having *any* guiding is likely to be a big enough improvement that a separate scope will serve you well (unless nonrigid mount, mirror flop, etc.). 

Great color in the nebulosity -- but, um, are there really that many purple stars? (Spoiler: There are not 🙂 ) If you could remove the stars (e.g. starnet++) and process the nebulosity separately for this excellent result*, then add the stars back in, it would be even better. I'm totally unfamiliar with Luminar; would your workflow allow that kind of manipulation? Also, detail and your composition rock as well.

*Or you could remove the stars from your final result here, grab them from your original image before much processing, and stick them back in that way.

What did you use for processing?

Nice! And hello from far-away Madison!

The various sub-disciplines have very different requirements, especially planetary vs. deep-sky, and even within deep-sky you might have different needs depending on your targets (big emission nebulae? Small galaxies?).

What would you like to image? What level of light pollution are you working in? And what sort of optics do you have at your disposal?

You could also give starnet++ a try for star removal. I was able to get much better results with that right off the bat than from Photoshop tweaks. As vlaiv says, after you've registered your NB and RGB images and run starnet++ on the latter to get a no-stars layer, you can do a "difference" blend mode in Photoshop and "stamp visible" to create a stars-only layer. Process that and your NB stuff, then add the stars back on top and set blend mode to "lighten".

+1 on 183MM-Pro + ~350mm. I really like mine a lot. Resolves fine nebulosity detail visibly better than my DSLR. Confident it will do better still once my (*@&% guiding is sorted.

Sorry, I can't find it. My best memory of their analysis -- which was supported by data, but you only have my word for it -- was that "seeing wobbles" are such high-frequency phenomena that you'd need absurdly fast exposures, AND processing, AND mechanical response the pulses, in order to chase them in the first place. Certainly the Jupiter image is wiggling at much more than 1 Hz -- I'd guesstimate more like 10 or more. So even 1-second exposures would be integrating quite a few of those.

Mind you, I've no interest in flogging an angels/pinhead argument here, especially since I don't have the data myself. I do advocate is that one be open to experimentation. If 3 seconds works for you, more power to ya. It's not as if I've got my own guiding dialed in yet, tell you that for free.

I've seen a recent article that seemed to debunk the "chasing the seeing" concept pretty thoroughly and argued that you should use the shortest cycle that gave a sufficient SNR. I will try to rediscover it.

Of course, the other option for imaging from light-polluted areas is to pick a narrowband wavelength which predominates in the light from your target, and use that as a luminance channel. It will emphasize whatever color its wavelength falls within (e.g. H-alpha will preferentially brighten the red areas of an emission nebula), but sometimes that's perfectly fine. If I'm shooting the North American Nebula, it's all red anyway.

That won't do very well on, say, a reflection nebula. Using H-alpha for luminance on the Trifid is going to leave you with some pretty dim blue areas.

I don't think the wavelengths of the three commonest narrowband filters map very well to creating a synthetic L that includes R, G, and B. Hydrogen-beta for blue, maybe, and O-III for green, but it's hardly ideal.