I plan to look at planets and brighter DSO (Messier). I feel comfortable finding them, but I think having the StarSense at least as an option sounds interesting.
Would you share the criteria you used to decide on the first four scopes? You see, you have asked us to evaluate them but we don't know all of your criteria. And since you have fairly few posts and are posting in the beginner forum I presume you don't have a lot of experience to draw on. So share the basis of your decision.
The three links/articles I put in the RESOURCES section of the second post in this thread explain the detail of what I am going to layout here.
Any telescope can be used to view the Moon, planets and the Messier objects. The power of telescopes is that they gather light, and they don't care where the light comes from. However, if you are deeply focused on one type of object, say the Moon and planets, then certain scopes are more optimized for that task, but it can still be used for other things. That is why many of us have more than one scope.
For a telescope, aperture is like horsepower in a car, the more you have the more powerful your telescope will be when you are viewing the Moon, planets and DSOs. The larger the aperture of the telescope, the more detail you can see.
The Sun is the one target where larger aperture is not really needed. It is so bright we have to block out over 99% of its light in order to observe it.
Messier saw the items on the list and his scopes were not likely much better than the three 102 mm scopes you listed. However his sky was likely much darker than yours, and that makes a big difference.
The Messier list is a collection of things he did not want to look at. He was primarily a comet hunter so the list was of things that might be mistaken for comets. But we like it because they are some of the brighter DSOs, though several are quite challenging in today's light polluted sky.
About 3/4 of the Messier objects can be seen with binoculars from darker locations, so that 80 mm will do the job too. But there is the ability to identify that something is there and there is the amount of detail you can see. They are not the same. The more aperture you have the more detail you can see.
Messier with Binoculars
The Moon is there pretty much all the time and you can spend a lifetime observing the Moon. Planets are not always in the sky and other than Jupiter and Saturn, are basically round balls with little to no detail. You will spend more time on DSOs than you might think and DSOs benefit from aperture above all else.
Questions: When I am helping someone pick a telescope, these are my first questions along with an estimated budget.
- Where will you store the scope? Do you have a garage or a shed?
- Where will you use it? Home? Remote sites? Take it on airplanes?
- How will you move it? Carry by hand, cart, ???
- Does it have to fit in a car? What Car?
- Is this for family vacations so it has to be small and compact?
Budget: What did you include?
- Telescope = optical tube, mount
- Eyepieces - you will likely want more than what comes with the scope
- Observing chair - adjustable height is best
- Case for accessories - can be anything, I use a cat litter bucket.
- Binoculars - excellent companion to any telescope
- Charts, apps to help you identify what there is to see and how to find it
What is your light pollution situation? This will greatly impact what you can see.
If you live in a third floor walk up apartment, then size and weight are critical. That 8" Dob that I listed in my first post would not be a good choice.
If you have a home, or access to ground level storage, than that 6" or 8" Dob might be your best choice. I keep all of my observing equipment in the garage. My scopes range from 80 mm to 305 mm/12".
The smaller scopes I can pick up and carry, fully mounted and ready to go. My larger scope is on a hand truck so I can just tip it and roll it out, almost as easily as the small scopes. So where you will store it and where you will use it are significant factors in choosing a telescope.
I started with an 80 mm and enjoyed it a lot. However, within two months I purchased an 8"/203 mm Dob and quickly learned how to make it easy to move around. I have since upgraded that one to a 12"/305 mm Dob. but I still have the first 80 mm which I use for outreach events because it is a tracking scope.
Depending on your light pollution situation, you may have lots of stars in your sky, or very few. After pointing the scope at what you can see with your eyes, you will need to adopt a method of finding things. These are discussed at the link, Seven Ways to Find Things in the Sky, that I posted earlier. Which do you plan to use?
If you are in a very light polluted area, star hopping can work but it can be quite challenging. This is like following turn by turn written directions at night when you can't see some of the street signs, or the signs are not there at all.
If you are in a fairly dark area, star hopping can be very rewarding. Start at a bright object and work your way to your target. Many people find the hunt by this method as much fun as the actual observing.
Some people, like me, prefer to use other methods that do not rely on what can be seen naked eye or in the finder on the scope. I rarely star hop.
So, share your selection criteria so we know how best to advise you. This is more about you than about the telescope.
Edited by aeajr, 24 January 2021 - 10:43 AM.