Thank you all. I think I will get the red dot view finder. And I was looking into laser collimator’s. Is this one any good? https://www.highpointscientific.com/telescope-accessories/collimation-tools/laser-collimation/apertura-1-25-laser-collimator-with-45-angled-face-a-lc
Now I’m trying to decide if I should go with this instead https://www.highpointscientific.com/telescopes/dobsonian-telescopes/apertura-ad10-10inch-dobsonian-telescope-ad10
Trying to decide if the accessories are worth it
That scope is good. Whatever scope you end up with, you’ll end up customizing the accessories, but that’s a nice, usable package High Point Scientific is offering.
I bought a 6" dobsonian (Newtonian) telescope about 25 years ago. As I learned more about telescopes and astronomy, I made two discoveries, similar to advice already given above:
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I wish I had an axial mount, so that I could hook up a motor, or at least a single dial, to cancel out the rotation of the earth. It’s difficult to keep the telescope pointed steadily, even at the moon, without an axial mount. Trying to find comets, M objects and even stars, is much harder with the dobson mount.
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If all you want to do is just look at stuff, why not do it in comfort? I would advocate getting a powerful (and comfortable) pair of binoculars with wide apertures. That’s for gathering light. Then, you tie the binocs to some kind of frame, then get a reclining (cushy) lawn chair. Rest your neck. Keep looking stuff as it passes overhead. You can see a lot with binoculars, more than you might think. This is what I’ll do the next time I invest in something for astronomy.
Binoculars are a great recommendation for a beginner. The views can often be spectacular. I have a Celestron 10X70 set. You need to use them on a tripod to really enjoy them, though.
I don’t have a Telrad, but I do have a red-dot finder. The big problem with such finders in the city is that stars that are visible for star-hopping in a finderscope may not be visible in a non-magnifying finder. When you can only see a few dozen stars with the naked eye, you have to hope that your actual target is near one of them.
I think you mean equatorial mount, not axial. The two mount types most common are alt-azimuth (like a camera tripod), or equatorial. Equatorial mounts are a necessity for serious photography, but if you are just slewing around to look at the sky visually, they can be tricky. You also have to polar-align them (roughly for visual, tediously for photography). And they are useless for terrestrial viewing.
The most important thing about a mount is stability. A dobsonian doesn’t generally have this problem, but rickety or under-sized telescope mounts and tripods will absolutely destroy your love of viewing. Every time you touch the mount it vibrates and you have to wait for it to steady down. Those cheap telescopes with aluminum tripods that millions of kids got for Christmases past probably destroyed their desire to keep doing astronomy.
Thanks Sam! I had forgotten the term; was caught up on the idea of aligning the axes (of rotation, of the telescope and the Earth).
Yes, I would recommend a steady mount, if you go equatorial. A nice solid tripod, for instance.
I guess another newbie-luring trick that can “destroy desire to keep doing astronomy” is mentioning loudly, on the box or advertisements, that the telescope has a magnification of X, such as “200x magnification!” That’s not the important thing here; you want light-gathering power and good optics, so generally, assuming the manufacturer is legit, then the wider the lens / mirror, the better.
Thanks for the replies. And over the past weekend I actually have been thinking about getting a good pair of binoculars instead.
This is why I posted here. To get other ideas, and as a measure to not just impulse buy a telescope.
Still up in the air on things.
Another question. I’d just like opinions on how much difference I am likely to actually see between and 8" and a 10" scope. I live in NE Pennsylvania, right in between two mid sized cities (each one 10 to 15 miles away from me). My normal viewing will be in the area near my house. There are a few places out in the woods (about a 20 minute drive) that are clearings on top of hills that I can get to. But it still not that far from the city lights.
Any opinions?
Another question. I’d just like opinions on how much difference I am likely to actually see between and 8" and a 10" scope. I live in NE Pennsylvania, right in between two mid sized cities (each one 10 to 15 miles away from me). My normal viewing will be in the area near my house. There are a few places out in the woods (about a 20 minute drive) that are clearings on top of hills that I can get to. But it still not that far from the city lights.
Any opinions?
As has been mentioned before, the simple rule for aperture is “the bigger the better”. This is because aperture defines the area of the light-collecting device (mirror for reflectors, lens for refractors). This light-collecting capacity is therefore, as area, proportional not to aperture but to the square of the aperture: Twice the aperture will give you four times as much light. The +25% increase in aperture when you move from an 8’’ to a 10’’ thus translates to an increase of 56% in light collection. That is quite significant and can make a difference not just in how many stars you can see but also in the level of detail that you can see in any given object, for instance, the structure of spiral arms when you observe a galaxy.
Now obviously there is a trade-off here between aperture on the one hand and budget on the other; it’s up to you to decide whether the additional aperture is worth the additional money you need to fork over for it. But merely optically speaking, the difference between 8’’ and 10’’ is not neglible. An 8’’ is already a very useful telescope (so much so that German Wikipedia has a dedicated article about that size in a telescope), but 10’’ is better.
Aperture has two benefits, in collecting a greater number of photons, and in greater resolution. The light-bucket effect of collecting more photons is proportional to the square of the diameter, but the resolution is proportional to the diameter. And resolution can be significant for overcoming light pollution: Consider the sky as being made up of small patches (roughly speaking, pixels), each of the size of your minimum-resolvable detail. A star will always take up only one of those patches, no matter how small they are, and always contribute the same amount of light to that patch. In order to see a star through the light pollution, roughly speaking, it has to be producing more light in that patch than the light pollution is. But the amount of light pollution in any given patch is proportional to the size of the patch, and so smaller patches (i.e., higher resolution) decreases the pollution relative to the star.
Even aside from light pollution, resolution is also good for seeing interesting-looking astronomical objects. Some astronomical objects are inherently fuzzy, and so are going to continue to just look fuzzy at any resolution, but in some, greater resolution will let you see individual stars, spiral arms, or other detailed structures. This is what people really want, when what they think they want is magnification.
Ok. Thank you all. I think I made my final decision.
Apertura DT10 10" Dobsonian Telescope
Apertura 2x ED Barlow Lens - 2" - A-2XB2
Celestron X-Cel LX 9 mm 1.25" Eyepiece
Apertura 38mm Super Wide Angle 2" Eyepiece
Apertura AD Dobsonian Fan and Battery Holde
Apertura 1.25" Lunar & Planetary Filter Set #1
Celestron 1.25" Cheshire Collimation Eyepiece
How does it seem? I figure that with the included 22mm eyepiece, this covers the basics. Only thing is most of the items including the scope is back ordered.
And ideas on changes I should make? I’d like to keep the budget around what it is now.
Thank you all
I’ll differ from the others on aperture. Don’t forget that we respond to light logarithmically, so an increase in brightness may not even be perceptable.
The general rule of thumb for visual observing is that you have to go up in aperture by 50% for the result to be visible in most cases to the eye. So you would see a reasonable difference going from 8" to 12", but 8" to 10" will be marginal.
Or to look at it another way, the difference between 8" and 10" is about half a magnitude in brightness. So instead of being able to see stars down to 12th magnitude, you might get to 12.5. That is, if you are in a very dark zone. If your skies are light polluted, you won’t see that far down with either scope.
The drawback of the 10" scope is that it is substantially larger and heavier, and therefore less likely to be used at all. I have an 8" SCT scope on a CGEM equilateral mount, and just moving it and setting it up and polar aligning it is a major chore.
I suggest you check out a local astronomy club and go to a viewing night and try out some different scopes and get a feel for it. Or start out with a smaller dob, like a 6" or even a 4.5", use it for a while, and then buy the one you want ince you know exactly what you are looking for. A smaller, wider field scope will also help you learn the sky easier.
Question. With the eyepieces and Barlow I have listed (the Barlow will do 1.3 and 2 times), the low end magnification is pretty well covered, but at the high end it jumps from 180 to 277. Am I going to want something in between? And I don’t really need higher magnification than 277 for starters, right?
No, that level of jump in magnification is just fine. How much magnification you want depends on what you’re trying to look at. Deep sky objects (clusters, nebulas, galaxies) don’t need much magnification at all. Planets a little more and you really only want lots of magnification if you’re trying to split binary stars or something. 277 is plenty to start out with, you’ll only be able to see more with 277 vs 180 on really clear/smooth days.
Totally gratuitous comment here regarding the current comet in the sky:
I spotted it first using my (nautical*) binocs. Then, once I finally found it–and it was much higher in the sky and bigger than I had expected it to be–I could sort of see it with my eyes. I had to wait until at least an hour, more like 75 minutes, past sundown. Binocs for the win! 
*My only pair of binocs at present are sort of weird. They are fixed focus, so there is no focusing dial / knob. Then, there’s a compass built in that you can see at the bottom of your view as you look through them. When you press a button on top, a red light illuminates the compass. The whole thing is waterproof, and has a bright yellow, floaty pad as its neck strap. Great for using on deck of a sailboat in wet conditions, but at all other times I wish I had a more “terrestrial” type pair of binocs that had big lenses. I guess I could put it on my wish list.
FYI …just followed a link on my news feed to a live comet feed (Virtual telescope project) and saw this “Choosing your first telescope” recommended …
The current comet is a great example of something where binoculars are better than a telescope. Mostly due to the wider field of view. It’s also bright enough to see with binoculars instead of needing the larger aperture. In my telescope with even the widest field of view I can get it is just too magnified.
In general I always take binoculars when I go observing. Use the binoculars to find what I want to look at in the sky, and then look for it in the scope.