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"Even with a telescope your human eyes are limited to planets and the moon, that's it."

Andromeda, M42, star clusters, can all be seen with the naked eye, but only from a dark location, and unfortunately not in most cities. I've seen scores of galaxies with just a 8.75" reflector. The virgo cluster that's available at this time of year is amazing.

I agree with most of the rest of your post though, especially the weight thing.

I'd also suggest that learning to star-hop from one object to another is a great way to learn the sky, but it does put newcomers off sometimes.

You can see M42 with just binoculars!

I could get NGC 7635 in my meade LX90 from my light polluted suburban backyard.

Really dunno where this moon and planets only thing comes from.

There's astrophotography and then there's astrophotography, however - and you get drawn deeper and deeper into it.

I have a few scopes, but mostly use an 8" celestron schmidt-cassegrain - it's a decent all-rounder for astrophotography, particularly as I mostly do deep sky stuff.

I started with a simple T-adapter and a DSLR, and of course, you start as you describe playing with the exposure, the iso - but then you want to see fainter objects, and the noise starts being a problem, so you learn about computational techniques for frame stacking and noise reduction, but those have their limits, and the results you're getting are so-so, so...

You buy a peltier cooled CCD. You upgrade your mount because you aren't satisfied with the level of backlash you're getting. You get a star tracker. You learn several suites of astrophotographic software before settling on three.

Now you're taking images of deep sky objects, but they just don't have that certain something - so you go and buy filters - hydrogen alpha, OIII, RGB, and more, and you start getting some images you're impressed by - but... wouldn't it be great if you could just capture a bit more of that dim halo... maybe I should buy a bigger telescope. Maybe I need a dome to keep conditions more constant. Perhaps I should go on holiday and lug my telescope, counterweights and all, to the other side of the planet, and hang out up a mountain.

No, this is madness. So long as you stick with what you describe and don't go down the slippery slope as I did. With the setup you describe you can still do neat stuff like observing the Galilean moons and plotting their ephemerides, and take stunning photos of the moon and even the sun with a simple solar filter.

Yup, no idea what GP is talking about, most dobs aren't really great for AP since the focal plane isn't in the right location.

I'm a huge photo-nerd but I took one look at AP and was like "nope!" for the exact above reasons + extremely long capture times. We're talking hours of frames to see some things.

It's mostly automated.

About capturing a bit more fo that dim halo, I always wondered... Wouldn't a secondary scope (with similar characteristics) result in an increased light gathering potential? I've also tried to look into visible-light interferometry, but there aren't many accessible resources on the subject.

My feeling is that there is a point in equipment in which you are simply better off getting a new rig (to work in paralell) than trying to get slightly bigger aperture (let's face it, 16" vs 14" is not as dramatic in light gathering and image quality as 8" vs 6"), but I'm not sure where that point lies.

But you also need another camera and probably another mount too. The scope is actually the cheapest component in a astrophotography setup. Probably the 80% of the cost is the mount+the camera.

Absolutely. Then again, there are limits. I remember an old Meade model (no longer available) that was a 20", $36k monster. I was beautiful, and they sold it as an observatory-grade instrument. But the 16" models were priced close to $10k, so it sort of made sense (in that particular case) to duplicate the rig. My "napkin analysis" was:

20" diameter, ~315 squared inches of area[0], $36k

2x 16 inches diameter, ~402 squared inches of area, $20k

This prices did include mounts, but back then (more than 10 years ago) I wasn't very knowledgeable and I honestly don't know if they were good mounts. So there was margin to increase the light gathering and having spare money for the new camera.

Still, the most interesting use for multiple telescopes would be building and interferometer. I'll keep looking into that, with the procesing power available in todays machines it should be doable.

[0] I know the secondary mirror obstructs the light gathering, but I don't have precise figures, so let's go with it the area of the main mirror.

I just went straight to the cooled CCD/C11/hyperstar and don't repent. I would like a better mount though, but my EQ6 is just fine. Now I actually need a smaller scope :)

You are severely hurting your argument by making false statements about what is possible to see with the naked eye and what kind of diameter telescope is required.

An 20cm reflector is a very reasonable telescope that won't break the bank, will fit into most cars, and will enable you to see a large number of galaxies and nebulae with the naked eye. The claim that you need a 100cm telescope to do so is ludicrous and contradicted by all of established astronomy.

Which galaxies? Andromeda maybe. I'm talking of a city or suburban environment. Of course if you go really far into the forest, you can see a galaxy. But it's a hassle, how many times a year you can do that?

> I'm talking of a city or suburban environment.

You are seriously moving the goalposts. You're somehow claiming that it makes more sense to spend tens of thousands of dollars on a huge telescope that you can't even transport in a consumer-sized vehicle than it does to simply drive somewhere that light pollution isn't a problem?

Astronomy is one of those things that you simply can't do well in an urban environment. Hiking or mountain climbing is another. You just have to accept it as one of the trade-offs of living in the city. No one forced you to live in a city. If astronomy is important to you, you can either put up with traveling for dark skies, or go move somewhere that doesn't suffer from bad light pollution. And if you are willing to spend the money to buy a one-meter scope, then astronomy is obviously very important to you.

Depends what it is that appeals about a telescope. If you want to see the most detailed possible realtime pictures of the ISS/Jupiter/Mars/etc. from your apartment, an Internet stream is going to be much better quality than anything you can produce with your own gear. So if you're using a telescope at all it's because you care about in some sense "seeing it with my own eyes". For some people using a camera "breaks" that feeling.

You can see the entire messier catalog, quite well, with a pair of binoculars. 1 meter is a fucking ludicrous diameter.

Sure, if you are in the middle of the chilean desert.

That's not really how telescopes work. If it's light pollution additional aperture does not by itself preferentially distinguish between terrestrial and extra terrestrial light. If it's humidity, radiated heat and particulate matter you'll hit the diffraction limit of your local atmosphere before you hit the resolution of a half meter scope.

N.B. if you have the money to buy a 1 meter scope and motorized mount sufficient for it you have the money to take a lot of trips with pair of binoculars to the Chilean desert.

I have a big-ass telescope and it's the main reason I can see stuff in light pollution. The trick, that I'm sure you know, is to pickup a bucket-load of light, filter the pollution light and let pass the star light. They are different colors, basically.

Not really sure what you're talking about.

I've seen at least 6-7 galaxies/nebulae from my 8" Dobsonian and plan to try and find more this year. You just need to get out to an area with low light pollution. FWIW this is from the deck of my house(one of the benefits of living in a rural area) but totally possible to do.

There's also something surreal about seeing the milky way streaking across the sky with the naked eye. Worth it to get away from the city for that alone.

I have an 8" SCT and can see many galaxies, nebulae and clusters with it when we go to our dark spot. You can even see the spot on Jupiter on a really good night. They don't look like the hubble photographs of the galaxies, but there's something just breath-taking about seeing it with your own eyes, in real-time.

"I don't see anything, just a blurry spot"

"That's it! That's the galaxy."

"You sure? I think it might just be a smudge on the lense."

"No, no. Try moving where you're focusing your vision, around it, instead of looking at it directly. So you're viewing it mostly with your peripheral vision."

"Woah."

Here is a tip for those on a limited budget. Get an inexpensive telescope you can afford but can only see a few planets and the moon. Take it to a star party and set it up and aim it at a planet or the moon. Walk over to the other people who have the expensive setup with the computerized mounts, expensive and large lens & etc and ask to take a peek. These hobbyists typically love to share and will usually be happy to explain in great detail what galaxy, nebula or object you are looking at and the technical details of their setup if you ask.

I have gone to such events without a telescope and most of them were more than happy to let us take a peek. One of them let my oldest daughter request objects to see and he entered the request in one of those nice automated setups.

Galaxies are visible with naked eye, $200 dobsonian can see quasars.

Do you have any photos uploaded somewhere public?

yes, https://www.astrobin.com/users/aortega/

sure a robot mount and photo stacking changes everything, but makes the entry price jump from 500$ top to 2k$, which would just turn down any beginner

Photo stacking software is free.

A very good robot mount plus telescope can be had for 800 us$ (Nexstar 6SE)

With a naked eye you can also see star clusters and nebulas. Of course, everything will look more impressive in the photo, bu still.

Star clusters are just a lot of point-like stars, and nebulas are really faint, if visible at all in the city. Though globular clusters are cool.