44 replies to this topic

[Jon Isaacs]

During the summer when I am setting up the 25" in 100 deg temps I wonder if it is all worth it. Then I look at m22 and say to myself "darned right it is". I little bit of hard work on the front end reaps many benefits on the back end. 

 

Thinking about the OP's opinion that a 6" is the "best telescope" for advanced observers I would have to humbly disagree. While such an observer can really make a 6" scope hum it is simply not enough aperture to hold ones interest for more then a few objects. IMO a 16" f/5 or an 18" f/4.5 hits the sweet spot for the advanced observer. Enough aperture to really go deep and portable enough to make set up easy.

 

Kevin et. al. 

 

I just don't think one can make generalizations about which what's the best scope. . If someone finds a scope that works for them, that's as much as one can hope for.  There's just too many things going on ..

 

How much time do you have?  How often are the skies clear? how dark are the skies?  Are there dark skies nearby,  how strong and tall are you,  what do enjoy looking at.  What type of scopes do you enjoy.  What are you financial resources ? The list is endless . 

 

I'm 70, retired , I have the time.  The skies are often clear and relatively dark,  clear skies are within an hour's drive and i am fortunate to have 4 acres with a small home and a good sized garage for scope storage . I spend a week to 2 weeks a month our here with the primary goal of observing. 

 

It takes me 5 minutes the first night to take the cover off,  attach the handles and roll the 22 inch out and remove the handles.  The next night , its about 2 minutes . I spend a lot of time observing,  550 hours last year, i like big scopes and I'm in a situation where it's very doable . A 6 inch or 8 inch would not be a good fit. 

 

But for many,  a 6 inch or an 8 inch is good fit.  From my urban backyard , I spend a lot of time with 3 inch and 4 inch scopes with my big scopes being a 10 inch and a 13 inch . If i were in another situation,  they could be one scope and an 8 inch or a 6 inch.

 

I will say this is response to Gary's "Scopes grow bigger with time. "

 

That has not been my experience.  For me , even my biggest scope seems more and more manageable with time . When i first purchased my 25 inch F/5 Obsession,  it seemed like a monster..  No surprise there.  But as time passed,  I came to see it as just a big scope but not all that big. 

 

My observation is that one's largest scope will always seem intimidating , by constrast , the second largest will see very manageable.  When i got the 16 inch , suddenly the 12.5 inch seemed to have lost a substantial amount of weight and bulk and become a featherweight ..

 

Jon

[EJN]

I just don't think one can make generalizations about which what's the best scope.

 

It has been settled for all time. Case closed.

 

http://davetrott.com...fect-telescope/

[Keith Rivich]

It has been settled for all time. Case closed.

 

http://davetrott.com...fect-telescope/

Unfortunately time is relative here on CN forums...

[gwlee]

During the summer when I am setting up the 25" in 100 deg temps I wonder if it is all worth it. Then I look at m22 and say to myself "darned right it is". I little bit of hard work on the front end reaps many benefits on the back end. 

 

Thinking about the OP's opinion that a 6" is the "best telescope" for advanced observers I would have to humbly disagree. While such an observer can really make a 6" scope hum it is simply not enough aperture to hold ones interest for more then a few objects. IMO a 16" f/5 or an 18" f/4.5 hits the sweet spot for the advanced observer. Enough aperture to really go deep and portable enough to make set up easy.

 I wouldn’t say any that any telescope is the “best telescope” for experienced users. I cringe at the thought of owning 16-18 inch scope. Used them often enough when I belonged to a big metro club and appreciate what they can do that a 6-8 inch scope can’t, but know that I wouldn’t use one. 

[terraclarke]

Now my only Newtonian, the 6” F4.5 that I built while in High School is 51 years old this year. It even got to take a fieldtrip to Stellafane a couple of years ago. I continue to make little upgrades like flocking the tube with proto-star flockboard and adding an Astrozap flex dew shield. Most recently it got a finder upgrade a few months ago, a matching Stellarvue RASI 50mm finder with an illuminated reticle (not shown).

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Edited by terraclarke, 15 July 2018 - 06:15 AM.

[stargazer193857]

From my use of 6" f8 and 8" f6, I can vouch that the 6" is lighter and more forgiving on collimation. The 8" is much brighter though. I currently have a 6" f5. It is nice for finding many objects, and does well on planets. The atmosphere and concrete are great equalizers.

At a dark sky site, looking at globular clusters, you will want a 10". And dim M31 dust lanes will want the 10" too. Use a 6" while you build a lighter 10".

[Keith Rivich]

 I wouldn’t say any that any telescope is the “best telescope” for experienced users. I cringe at the thought of owning 16-18 inch scope. Used them often enough when I belonged to a big metro club and appreciate what they can do that a 6-8 inch scope can’t, but know that I wouldn’t use one. 

Funny hobby, isn't it... I cringe at the thought of NOT having my 18 and 25" scopes. 

[Deep13]

My DIY 6" is on the ATM forum under "airline portable scope," if anyone is interested.

[gwlee]

Funny hobby, isn't it... I cringe at the thought of NOT having my 18 and 25" scopes. 

People choose what works best for them based on their needs and experience. 

[Galicapernistein]

After owning 12.5 and 15 inch scopes, I appreciate my 8” dobs much more. Now that I know what to look for, I’m seeing things that I didn’t know I could when I started out with my first Orion 8” dob. The amount of detail visible in galaxies is the most surprising. As has been said here many times before, all large scopes do is magnify galaxies, they don’t increase their intrinsic brightness. So now I try to see the galaxies as simply smaller versions of what I saw in my bigger scopes, and I’m seeing things I never thought I could. I just had to change my expectations, and observing techniques. I’m getting to the point where I don’t want an F5 scope of any size, because of my aging eyes and their short depth of focus. So for me, going smaller and slower with an 8” F6, or even a 6” F8, is not only doable, but probable, maybe in the near future. When I want to do some serious observing, I break out the 8” F9. I haven’t even scratched the surface of what this scope can do.

Edited by Galicapernistein, 16 July 2018 - 09:53 AM.

[stargazer193857]

Definite pros and cons to different sizes. Mass produced costs less, though.

With 8" f6 vs 10" f5, both should be moved in 2 pieces. But the 8" can moved in one piece if you really need to dodge a tree. Still, you will want more aperture.

[stargazer193857]

6" is enough to get interesting views. M13 starts to break up. Planets start to get beef that the 4" can't muster. The view is wider. And the scope is portable.

But 6" is mainly a grab n go. If you drive way out some place dark, you will want a 10" to enjoy the night. Even at home, the 10" will be much better on planets.

[dscarpa]

 Long ago I had a 6" F8 with 1/8 wave optics and it gave views comparable to my WO ZS110 refractor for planets but brighter on DSOs and not far behind my IM715D mak with a much wider FOV. David 

[barbie]

I'm pretty much in the same situation as you are David.  I have a 6" F8 Newtonian with 1/12 wave optics(bench tested) and a recently acquired 4" f9 ED apo refractor.  The 6" F8 and the refractor provide outstanding views of the planets but the 6" will dig a little deeper for DSO's when that bug strikes me again someday(when the planets are at Wintertime oppositions) and when it's usually endlessly cloudy during my winter months.  With these two scopes plus my C90 and 40 year old homebuilt 4.25" F3.8 newtonian on a tabletop mounting, I'm pretty much set for the rest of my life as far as portable grab and go observing, which is what I primarily do.

[gwlee]

i own both 6”f8 and 8”f6 scopes, and the lower weight and slightly smaller size of the 6”f8 give it a big advantage for me at this observing site, so it’s my most used scope by far. 

 

If you can EASILY handle the larger 8”, it’s likely the better choice for most people. Scopes seem to grow bigger and heavier after the new wears off though.

My 6”f8 (my 4th) went to a good home this afternoon, so my 8”f6 (also my 4th) is my only reflector now. It’s really too large and bulky for all the tree dodging over broken ground required at this forested mountain site, but i am steadily taking out large trees that have succumbed to drought and bark beetles.

 

So far, I have managed open a couple of spots with views to the south that allow leaving the scope in one position for up to an hour (15 degree window) making the scope somewhat useable with advance planning. I am also hoping to take a few pounds out of its total weight with a new base that Ken Fiscus built for me and I am modifying. I also have a small refractor that’s particularly suitable for tree dodging, so I am hoping to be able to get along without the 6”f8 at this site now. 

Edited by gwlee, 20 August 2018 - 12:31 AM.

[Ohmless]

Love my 6" f/5 reflector.  Previously had a 4" f/10 achromat that could lightly resolve some of M13.  My 6" has no problem doing this.  I had problems with floaters that were fixed by using a binoviewer and the shorter focal ratio, larger aperture scope. 

 

I am disabled with my back and couldn't imagine ever being able to tear down a larger scope and mount when done observing.  Setting up is not the problem but after a night of observing and frequent standing the tear down is already as tough of a job as I want to tackle.

 

I have mine mounted on a motorized cg4 and I often have to break it down to carry the parts into the house.  It is a great mount for what I use it for(sketching and long planetary viewing) and highly recommend it.  I am considering trying the twilight 2 mount but it doesn't weigh much less than the cg4 so I will wait on that.

 

I also enjoy recreating historic observations as part of my hobby.  One of Herschel's scopes was approximately 6" aperture and same with one of the Strauves.  I even made a lens cap for my 4" refractor out of an oatmeal box lid that I painted black and cut out a 1cm central aperture hole for doing Galileo's observations.

 

As a second pick for aperture, I greatly enjoyed viewing through the 76mm reflector I had in high school.

[nicoledoula]

6" dobs, so versatile the mere mention of them stirs a need to express braggadocio among giant Dob owners?  Telescope envy in reverse? Obsession can be more than a brand name. Not sure telling people how they can't live without their expensive giant scopes is any help to people looking at/happy with 6-8" scopes. As if no one knew aperture had advantages. Thanks guys. Opinions duly noted.  Can't decide between 6" F/8 and 8" F/6. And don't need any help. Always been leaning towards F/8, lighter weight, quicker cooldown, easier collimation. Seems about right.

[gwlee]

6" dobs, so versatile the mere mention of them stirs a need to express braggadocio among giant Dob owners?  Telescope envy in reverse? Obsession can be more than a brand name. Not sure telling people how they can't live without their expensive giant scopes is any help to people looking at/happy with 6-8" scopes. As if no one knew aperture had advantages. Thanks guys. Opinions duly noted.  Can't decide between 6" F/8 and 8" F/6. And don't need any help. Always been leaning towards F/8, lighter weight, quicker cooldown, easier collimation. Seems about right.

I have always strongly preferred owning just one scope and using it for everything along with a handheld binocular. The 6”f8 is just large enough to give me pleasing views of all the main types of celestial objects from this fairly dark site, and just light enough for me to carry it over rough, sloping ground in one piece for the frequent tree dodging required here, so it’s been my most used scope here. 

 

However, since I have decided to keep two scopes for now, I kept the largest, an 8”f6 Dob for its greater performance, and kept the smallest, my itty bitty refractor, for its greater portability and widest fields of view. Together, they offer a more versatile combination than a single 6”f8, which sounds very rational, but it I not sure that I won’t be hunting for another 6”f8 before long. 

Edited by gwlee, 21 August 2018 - 11:55 AM.

[stargazer193857]

F8 is planetary. You can do well on DSO by zooming in. But you just can't get a rich wide field. The secondary is too small. Oh, you can make the secondary bigger, but then it is less optimized for planetary. 8" and above really is more versatile. The reason to get the 6" is to save $150 and have a lighter scope that even a beginner can collimate.

[stargazer193857]

I have always strongly preferred owning just one scope and using it for everything along with a handheld binocular. The 6”f8 is just large enough to give me pleasing views of all the main types of celestial objects from this fairly dark site, and just light enough for me to carry it over rough, sloping ground in one piece for the frequent tree dodging required here, so it’s been my most used scope here.

However, since I have decided to keep two scopes for now, I kept the largest, an 8”f6 Dob for its greater performance, and kept the smallest, my itty bitty refractor, for its greater portability and widest fields of view. Together, they offer a more versatile combination than a single 6”f8, which sounds very rational, but it I not sure that I won’t be hunting for another 6”f8 before long.

We think similarly. My solution is a fast ultralight 11" with an optical finder.