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Keep my 8” dob or sell and get a celestron nextar

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#1 nukes1810

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Posted 13 August 2019 - 11:47 AM

Hi every one newbi here from a Abilene Tex. So I started about 1yr a go when I bought a 60az from a local hobby shop which I quickly got board and frustrated with and got a 8” collapsible skywatcher dob for $250 used. Huge difference and was completely happy with it and started to get into Astrophotography too(still learning) but thing is I got board with just looking at Jupiter Saturn and the moon. And a little frustrated that the mount it is on keeps moving and no matter how much weight I put on the butt end. So question is I want a goto telescope or one with tracking but I don’t want to break my bank so would a celestron nextar series would I have better luck, is there any mods I can do to my son to add tracking or goto function or is there a scope any one can recommend that would be around $400.
Thank you in advance

#2 clearwaterdave

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Posted 13 August 2019 - 12:03 PM

I think you should find and fix your balance problem.,and that you need to get an atlas or star app. and learn to starhop.,Soon enough you will be able to find and view anything 8"s will show.,

   I think you would be let down with 4" after looking through 8"s.,and the skill of starhopping is a life long investment.,a goto scope of 4" maybe not.,good luck with your choices.,

 Astrophotography is another hobby,to be discussed in another forum.,


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#3 Chesterguy1

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Posted 13 August 2019 - 12:21 PM

Nukes:

 

I think you are at cross purposes. An 8" dob is an excellent visual instrument and should provide you with years of interesting targets as long as you give yourself time to learn where the stuff is and are realistic about what objects will look like. I have an 8" dob it it is my most used scope filling the niche between big aperture, but more involved set up, and small aperture grab and go.

 

Most here will tell you that when it comes to learning and doing astrophotography (except, say cellphone snaps of the moon) a small scope (100 mm or smaller) is the best way to begin, but--and this is really IMPORTANT--the mount is critical and must be stable, track accurately and be more than adequate in handling the weight/length of scope you choose to get decent results. I'm not saying you can't find something, particularly used, but $400 for a goto, even tracking mount, is just likely to cause you frustration. In my view, AP should be viewed as a distinctly separate enterprise.

 

Chesterguy


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#4 nukes1810

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Posted 13 August 2019 - 12:28 PM

Thanks for the replies so far I have a 3x Barlow and a 9mm eyepiece and a 20mm I believe to make this experiences mvetter what other instruments will I need. Also I have severe adhd so reading long how to is not really my thing don’t have the attraction span for it but can someone pony me to the right place where to find stuff and to starship of it’s not too much trouble and is there any way I can valance the scope currently I have 2 2lb ankle weights at the bottom

#5 Napp

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Posted 13 August 2019 - 12:34 PM

I recommend you take your scope to an outreach event or star party of your local astronomy club.  Members can help you diagnose and resolve what’s going on with your mount.  Join the club and keep going to observing sessions and star parties.  There is no better way to learn scopes and observing than with experienced observers.  They can teach you star hopping.  I see there is a club in Abilene.  https://www.go-astro...y-club.php?ID=1

 

There is is no way I can recommend a cheap goto.  You are sacrificing optics to buy a cheaply built goto. 


Edited by Napp, 13 August 2019 - 12:36 PM.

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#6 MalVeauX

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Posted 13 August 2019 - 12:42 PM

Heya,

 

I would work on balance on your dob. There's lots of easy modifications to do to tighten it up and balance it so that it moves with your pinky and doesn't drift with an eyepiece, etc.

 

To add tracking, you can start researching equatorial platforms. This is a platform that will let your scope sit on it and it will track a few minutes and is meant for dobs. Great way to add a few minutes of tracking to your setup. You can buy kits or pre-made, there are all kinds, etc. Just look into it.

 

To get something with 8" aperture that tracks, with your budget, someone basically has to give you a steal of a deal that would involve selling your scope and getting $200ish back, then somehow getting a used Nexstar 8SE for around $600 used. This is not unheard of. It's possible. But it's about the only way to get a tracking setup with an 8" aperture that is useful and easy to use. It's not better. It's just another way to do things. No one is going to argue with a C8's optics, they're good enough, no worse than a commercial 8" dob's optics, so there's no argument either way there. It's just a matter of lining up the deals to make this work.

 

Alternatively, this is where you shop for a used AVX. It won't be $400. It may be closer to $600 used. But this is a 30lb mount that will handle your 8" dob and track just fine. You just get some rings and a dovetail for your reflector and it will mount to the saddle of the AVX. The AVX will easily handle an 8" reflector so you could do visual and even consider some imaging with it (planetary/lunar imaging).

 

Very best,



#7 sg6

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Posted 13 August 2019 - 01:06 PM

Seems you are having a problem finding objects to observe, as in cannot point the scope at them.

Say this as you say bored of Jupiter, Saturn, moon.

In general they are visible and most other objects are not really.

So in your mind is a goto.

 

They are no real upgrades to add goto to an existing dobsonian mount.

There used to be but they seem to be off the market.

 

So if you want goto it would have to be a "new" scope, new as in not the one you have at present.

 

A goto is not "automatic".

There is still a fair bit on manual input especially at the start.

 

How well can you stand outside and point to where objects are?

M31, M13, M92, C14, Albireo, Almaak, Mizar, M57.

You need to know where such things are in order to aim the scope.

 

Where are you as a club may help, but a club is not there to teach, help maybe and most likely to offer advice. What a club can do is point out where things are for you to later try.

 

Astrophotography and a dobsonian do not go together as a set up.

Astrophotography scopes are usually small and they need an equitorial mount with motors in order to track. There really is no alternative.

 

To aim scope a well set up finder is necessary. You initially aim by the finder, then observe through the main scope.

 

You balance sounds wrong. adding weight to the rear will simply make the scope point upwards. I guess you need a bit more friction in the movement but less or no weight. Not familiar with the scope so unable to offer ideas. That is an area where a club may be able to make sensible suggestions.

 

To find anything usually a low power eyepiece is required as that means a wide view. Easy eyepiece is a 32mm plossl. Although a 25mm Paradigm delivers almost the same and may be a better option.

 

If required set up the finder accurately.

Then if necessary work out where things are.

Then locate them with a wider eyepiece like a 32mm plossl or a 25mm Paradigm.

 

If all fails then ask again about a goto. My goto's are small refractors so wide field, this makes using them fairly easy. Goto I have is a Meade ETX-70, and a Skywatcher Az GTi with a 72mm ED refractor. Neither are high power - 70-100x is all I expect if lucky.


Edited by sg6, 13 August 2019 - 01:08 PM.


#8 Subaru45

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Posted 13 August 2019 - 01:31 PM

Myself, I would work with the dob, and look into putting it on an EQ platform.



#9 vtornado

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Posted 13 August 2019 - 02:17 PM

Hello Nukes and welcome to cloudy nights.

 

You need to learn to find things with your dob.

 

To help you do this.

1) get a 50mm raci finder scope. (optional but helps).

2) download sky safari onto a tablet or smartphone.

3) buy a magnetic digital angle meter and mount it on your scope.

4) create a degree wheel or setting circle for your dob.

5) get a 32mm 1.25 inch or 30mm two inch eyepiece.  This maximizes the field of view of your main scope

 

sky safari will give you the instaneous coordinates for any object, in real time for your location.

It will show you the azimuth and altitude in degrees.

 

The angle guage will allow you to point the scope to the indicated altitude,

the degree wheel will allow you to point it in the azimuth.

This will get you very close so either the object will be in your finder, or it will just require

a little searching around.

 

Start with bright objcets first like double stars, and clusters, once you get the hang of it you

can try fainter objects like bright nebula an galaxies.

 

One thing thing to note about goto, ...

I assume you live in light pollution, almost everyone does.  Yes the goto will point your scope where you

need to look but many of objects in the catalog will be invisible.  2nd the reduced aperture of the goto

scope will leave the object invisible or disappointing, compared to your 8 inch dob.


Edited by vtornado, 13 August 2019 - 04:56 PM.

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#10 SeattleScott

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Posted 13 August 2019 - 03:56 PM

$400 isn’t much for a GoTo scope. You would be looking at a very small scope with questionable mechanical quality, or buying used. Of course buying a used GoTo scope offers no assurance or recourse if the GoTo doesn’t work. And people are more inclined to sell a GoTo scope if the GoTo no longer works. Not saying all used GoTo scopes are broken but there is certainly risk involved. I have purchased two used GoTo mounts and while both of them functioned well enough to pass initial inspection, neither really functioned satisfactorily for me. But they were still a fine value for the price.

So I tend to agree, work on making the Dob work better for you. At $400 you just don’t have a lot of options. And don’t worry about Astrophotography other than Moon and planets. Best bet for fixing your balance issues would be attending a star party, as suggested.

Scott

#11 ShaulaB

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Posted 13 August 2019 - 04:04 PM

Like others commenting, I really think you would be better off using what you have already. I would add a 30mm, or in the 30 range, eyepiece. The wider field of view will help a lot with star hopping. Combined with a right angle finder scope, a Telrad zero magnification finder device will help.

It takes some practice learning to star hop to a deep sky object that is not visible to the naked eye.star hopping is like a sport. The more you do it, practice, the better you get.

#12 whizbang

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Posted 13 August 2019 - 05:33 PM

Nukes,

 

The earlier advice is 100% on target.  You need to fix your balance problem, and, get an raci, and get a 32mm plossl.

 

A lot of folks here, myself included, would be happy to help you troubleshoot and correct the issues you are having.

 

Having good finders makes a give difference (improvement).  But adding finders up top also changes your balance.  Your best bet is to find a knowledgeable local  telescope expert.

 

Good luck.  Stick with that DOB.



#13 JOEinCO

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Posted 13 August 2019 - 05:51 PM

......And people are more inclined to sell a GoTo scope if the GoTo no longer works......

Not my experience at all through a dozen or so used GoTo mounts. I've had far more trouble with two poorly functioning brand new Explore Scientific GoTo mounts. 

 

But posts above are correct. Going to be near-impossible to get better telescope performance in a GoTo package for $400. And your self-admitted lack of attention span is not going to mesh well with a GoTo mount and it's required learning process and alignment procedures. 


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#14 SeattleScott

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Posted 13 August 2019 - 06:35 PM

Haha well at least you had a warranty!

I suspect most used GoTo mounts work fine, but people just couldn’t figure them out or decided it wasn’t for them. And I probably would have been happy with the performance of one of them 15 years ago when I was starting out. My satisfaction is really more related to the build quality of the mount and subpar QC than anything the previous owner might have done to it. But yeah a $400 budget is tough, especially when the competition is an 8” Dob.

Scott

#15 Jond105

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Posted 13 August 2019 - 07:03 PM

Agree with all, I’d work on the dob. 

 

If you haven’t already, download an app for the tablet or phone, get a nice RA finder, and start looking for more objects. 

 

 

Im starting to think though, I had a 10” collapsible, you have an 8” using very little weighted eyepieces, are you tightening the knobs on the side to hold it steady? You shouldn’t need ankle weights in my opinion. I’m wondering if maybe you were missing the tightening knobs on the side now. 



#16 MikeTelescope

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Posted 13 August 2019 - 07:09 PM

Keep the Dob.  Any GoTo you can get for less than $400 is going to have much less aperture, and so you will likely be back viewing the planets and the moon, which you have said you are bored with.  Make a goal to find M22 (a globular cluster), M8 (an emission nebula), and M31 (Andromeda galaxy) before the end of August in your Dob.  All are easily found and will look great in the 8".  In particular after the full moon passes and the sky is darker.  Once you have practiced finding a few good deep space objects that showcase your 8" Dob, you may not want to go smaller just to get the GoTo. 

 

The GoTo has its own learning curve.  I was out at a dark site event a few weeks back.  Had my Dob set up in 10 minutes and was already observing while my neighbor was still setting up his GoTo and trying to align it.  He showed me what his GoTo said was M15, but it was just a nice patch of sky.  The alignment had failed.  An hour in, the battery died and he was done.  He looked through my Dob the rest of the night and said he was going to sell his GoTo and get a Dob.  


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#17 hcf

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Posted 13 August 2019 - 07:35 PM

Can you describe your Dob balance problem in a little detail? A picture of your setup might help too.

 

Maybe someone here can help you figure it out.


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#18 MikeTelescope

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Posted 13 August 2019 - 07:47 PM

And a little frustrated that the mount it is on keeps moving and no matter how much weight I put on the butt end. 

I use these on my 8" and 12" Dobs.  https://www.harborfr...nets-67156.html

 

They are 0.5 lb. each and only $3.  I put 8 of them in a sock and it sticks to the bottom of the tube.  I can slide it up and down to get the right balance, or remove individual weights from the sock.  I don't need to apply any tension on the bearings with this counterweight in place.  $25 solution that works for me.



#19 PPPPPP42

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Posted 13 August 2019 - 08:14 PM

A used Celestron 6SE (what I started with) can be had for under $500 used but you will need a few hundred more in extras to really get the best use out of it.

Its hard to justify going backwards in aperture size unless you are getting a very expensive refractor as a second scope.

Dobs are the king of cheap aperture so getting an 8" or better in anything else with goto gets expensive.

 

My advice is play around with what you have while you save up a whole lot more.  You already know that you plan to stick with astronomy from what you have tried already and the next step up would cost probably $1500 at least (and that's used stuff) by the time you get things all together.

 

I may have missed something in the above posts but deciding between an alt/az mount or an equatorial mount is your next step.  That's a long topic that has been covered to death in other posts but if you plan to do any serious astrophotography you will be getting an equatorial mount.


Edited by PPPPPP42, 13 August 2019 - 08:38 PM.


#20 nukes1810

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Posted 14 August 2019 - 11:29 AM

Thank you for all the advice I’ll work on improving the one I have I have attached a picture of the telescope I have. Problem im having is that it moves vertically, no matter how much I tighten the side handle/tightness 

https://drive.google...ew?usp=drivesdk


Edited by nukes1810, 14 August 2019 - 12:06 PM.


#21 clearwaterdave

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Posted 14 August 2019 - 06:44 PM

Try asking over in the reflector forum.,maybe someone has come up with a good fix for this problem on this scope.,cheers.,



#22 hcf

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Posted 14 August 2019 - 07:54 PM

Thank you for all the advice I’ll work on improving the one I have I have attached a picture of the telescope I have. Problem im having is that it moves vertically, no matter how much I tighten the side handle/tightness 

https://drive.google...ew?usp=drivesdk

 

I am assuming the scope moves down vertically because you have been adding weights to the mirror end. Does it move down even if you have no eyepiece? Or is the movement only with your heavier eyepieces. Also, have you been adding weight on top of the tube at the mirror end or under the tube? Ideally the weights should be added under the tube which is why people use magnetic weights.

 

Don't know much about tension adjustments for this scope, maybe someone who has a skywatcher collapsible dob will chime in. The reflector forums might also help, as clearwaterdave suggested. Here is a thread that talks about balancing dobs in general...

https://www.cloudyni...nter-balancing/



#23 Jond105

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Posted 14 August 2019 - 07:57 PM

I would tighten the side without the bearing and only use the bearing side as needed with my collapsible. It’s very strange the problem you seem  to be having. 



#24 pregulla

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Posted 15 August 2019 - 04:09 AM

I have SW 8" collapsible dob and it is very tolerant to balance issues. Balancing certainly makes things easier but it is capable of handling the 9x50 finder scope and some heavy eyepieces even without adding weights. 

 

Since you bought yours used, did it come with the handles that are aslo used to control altitude friction? 




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