Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Is this 4" f9.8 achro as good a deal as it looks?

  • Please log in to reply
41 replies to this topic

#1 James1996

James1996

    Explorer 1

  • -----
  • topic starter
  • Posts: 84
  • Joined: 18 Jun 2014
  • Loc: Green Springs Ohio

Posted 22 October 2019 - 07:35 AM

https://shop.astrono...ope-ota-20175-3 Because I think it looks like one.


Edited by James1996, 22 October 2019 - 07:39 AM.

  • zjc26138 and Bomber Bob like this

#2 wrvond

wrvond

    Surveyor 1

  • *****
  • Posts: 1781
  • Joined: 25 Sep 2014
  • Loc: West Virginia

Posted 22 October 2019 - 07:48 AM

It's a fair deal for a very good quality beginner scope.



#3 dmgriff

dmgriff

    Apollo

  • -----
  • Posts: 1162
  • Joined: 20 Sep 2006
  • Loc: 30 degrees latitude, USA

Posted 22 October 2019 - 08:05 AM

For a price comparison, a new Vixen (Synta/China) A80Mf f/11.x is 300usd. SkyWatcher is Synta's house brand. Both scopes are manufactured by the same company.

 

  https://www.vixenopt...cope-p/2603.htm

 

So, pricewise, it is a steal....

 

All depends on the quality of the objective, imo. I doubt that I would replace my Vixen (Japan) A105M f/9.5 if I looked thru the SkyWatcher, but, it should be a good  4in f/10 achro and very stable on a eq5 mount. I would expect noticeable CA on bright objects, more than the Vixen 105M (which is slight in my sight).

 

Oh...and the A105M runs 900usd.

 

Good viewing,

 

Dave


Edited by dmgriff, 22 October 2019 - 08:07 AM.


#4 James1996

James1996

    Explorer 1

  • -----
  • topic starter
  • Posts: 84
  • Joined: 18 Jun 2014
  • Loc: Green Springs Ohio

Posted 22 October 2019 - 08:20 AM

About Mounting it would this https://www.astronom...muth-mount.html work at or would need something more serious.


Edited by James1996, 22 October 2019 - 08:20 AM.

  • Bomber Bob likes this

#5 2696

2696

    Ranger 4

  • *****
  • Posts: 312
  • Joined: 27 May 2019

Posted 22 October 2019 - 09:01 AM

About Mounting it would this https://www.astronom...muth-mount.html work at or would need something more serious.


I would think that mount would be fine for the weight. The actual size could potentially be an issue but I'm not too sure. Either way, that mount has been out of stock for a while so if you want one like that you'll have to go for the Explore Scientific Twilight I, unfortunately it is I think $80 more than the Astro-tech one.
  • Jdrasberry likes this

#6 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 79602
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 22 October 2019 - 09:14 AM

I would think that mount would be fine for the weight. The actual size could potentially be an issue but I'm not too sure. Either way, that mount has been out of stock for a while so if you want one like that you'll have to go for the Explore Scientific Twilight I, unfortunately it is I think $80 more than the Astro-tech one.

 

I think the 4 inch F/10 would be too much for the Twilight 1. It's not a heavy scope but it's a long scope.

 

Jon


  • jeremiah2229 likes this

#7 James1996

James1996

    Explorer 1

  • -----
  • topic starter
  • Posts: 84
  • Joined: 18 Jun 2014
  • Loc: Green Springs Ohio

Posted 22 October 2019 - 09:26 AM

I think the 4 inch F/10 would be too much for the Twilight 1. It's not a heavy scope but it's a long scope.

 

Jon

What would you suggest then? Just curious it'll be a little while before I have the the money to buy anything like this.


Edited by James1996, 22 October 2019 - 09:26 AM.


#8 wrvond

wrvond

    Surveyor 1

  • *****
  • Posts: 1781
  • Joined: 25 Sep 2014
  • Loc: West Virginia

Posted 22 October 2019 - 09:31 AM

What would you suggest then? Just curious it'll be a little while before I have the the money to buy anything like this.

I put a Celestron 102mm on a CG4 that has worked well for visual.


  • Jon Isaacs likes this

#9 Jdrasberry

Jdrasberry

    Lift Off

  • -----
  • Posts: 24
  • Joined: 28 Sep 2018
  • Loc: Littleton, Colorado

Posted 22 October 2019 - 09:38 AM

What would you suggest then? Just curious it'll be a little while before I have the the money to buy anything like this.

Have you researched the price of a used refractor? Usually here on CN you can find a much better refractor than  you’re looking at so far for a lot less money. Same thing with the mount  to hold your long telescope.


Edited by Jdrasberry, 22 October 2019 - 09:40 AM.

  • gnowellsct, drd715 and 2696 like this

#10 csrlice12

csrlice12

    ISS

  • *****
  • Posts: 24915
  • Joined: 22 May 2012
  • Loc: Denver, CO

Posted 22 October 2019 - 10:41 AM

My OMNI 102 f10 rides the CG4 rather well, even at high mag with minimal CA.  It does NOT ride the Twilight 1...its way too long for it.  My 81mm f7.7 goes well with the Twilight 1, 4" is just a bit too much for this mount unless its an SCT or Mak.


  • Jon Isaacs and wrvond like this

#11 Binojunky

Binojunky

    Fly Me to the Moon

  • *****
  • Posts: 5640
  • Joined: 25 Dec 2010

Posted 22 October 2019 - 11:45 AM

A CG4 works OK, I had mine on a older EQ3-2 but threw the extruded Aluminium legs away and made new wood ones from one piece lengths of 3"x 2",s  cut to the height to suit me,D.


Edited by Binojunky, 22 October 2019 - 11:46 AM.


#12 grif 678

grif 678

    Apollo

  • *****
  • Posts: 1474
  • Joined: 22 Dec 2010
  • Loc: NC

Posted 22 October 2019 - 12:30 PM

If you could find a good Vixen/Celestron C102 OTA, with the great Japan optics, I would go with that instead. You see these occasionally for sell, but owners like them so much, they keep them. You could place an ad for one, someone may be willing to sell. I have seen several on ebay, I bought one there, and it was very good. But I would rather use CN instead.

You can check the ratings on the vixen C102 on excelsis telescope ratings, and see how great these are.


  • Terra Nova and Jdrasberry like this

#13 Jond105

Jond105

    Skylab

  • *****
  • Moderators
  • Posts: 4451
  • Joined: 19 Feb 2018
  • Loc: Detroit

Posted 22 October 2019 - 01:55 PM

I’d suggest hooking that up to a CG4 before attaching it to a budget AZ mount. 


  • wrvond likes this

#14 barbie

barbie

    Apollo

  • *****
  • Posts: 1006
  • Joined: 28 Jan 2013
  • Loc: Northeast Ohio

Posted 22 October 2019 - 02:14 PM

Same here. I had a C102 this past spring and was perfect for the CG-4 mount. I now use both of my apos on my CG-4 and it is a perfect match for them. The Astroview EQ from Orion is basically the same mount and with dual axis drives, works fantastically.
  • wrvond likes this

#15 Jond105

Jond105

    Skylab

  • *****
  • Moderators
  • Posts: 4451
  • Joined: 19 Feb 2018
  • Loc: Detroit

Posted 22 October 2019 - 02:22 PM

I should also add, if you go this route, the Orion SVP 16” extension fits the CG4 perfectly. For visual, you may want to consider it down the road, just to keep you off the ground when viewing certain altitudes. 


  • tony_spina and wrvond like this

#16 James1996

James1996

    Explorer 1

  • -----
  • topic starter
  • Posts: 84
  • Joined: 18 Jun 2014
  • Loc: Green Springs Ohio

Posted 22 October 2019 - 02:40 PM

I'll keep all that in mind thanks for the advice.



#17 MalVeauX

MalVeauX

    Fly Me to the Moon

  • *****
  • Posts: 5896
  • Joined: 25 Feb 2016
  • Loc: Florida

Posted 22 October 2019 - 03:10 PM

A 4" F10 frac with a 2" focuser for under $250 brand new is quite good.

 

The savings, I'm afraid, are lost to requiring a substantial mount. The typical $200 mounts will not handle that thing. I have a 120mm F8.3 and it's the same focal length, similar weight, and the Twilight 1 is brought to its knees. You'd have to basically get a much more substantial mount which costs significantly more, or get an EQ mount that can handle it and then either configure the EQ mount as an alt-az or use it as EQ. Kind of a compromise.

 

Unfortunately there are not any really solid Alt-Az mounts in the $200~300 range to handle these longer scopes. They handle those 4" F7 scopes ok. But the F10 scopes are a total different animal to mount. The moment arm is significant. Very hard to use with medium and high power, long dampening period. So really this is where a 4" F7 ED scope on a lighter mount tends to work out more often for folk, rather than a cheaper longer scope on a far more expensive mount.

 

Very best,


  • Terra Nova likes this

#18 gnowellsct

gnowellsct

    Hubble

  • *****
  • Posts: 15949
  • Joined: 24 Jun 2009

Posted 22 October 2019 - 03:27 PM

https://shop.astrono...ope-ota-20175-3 Because I think it looks like one.

As long as you understand what you're getting into with an achromat.  


  • 2696 likes this

#19 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 79602
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 22 October 2019 - 03:43 PM

What would you suggest then? Just curious it'll be a little while before I have the the money to buy anything like this.

 

James:

 

As others have suggested, the CG-4 is the apparent choice.  Looking at your equipment list, i see you have a Skywatcher 6 inch F/8 Dob.  I'm not sure what you're hoping to gain with this 4 inc F/10 achromatic refractor? 

 

Jon


  • Terra Nova and wrvond like this

#20 gnowellsct

gnowellsct

    Hubble

  • *****
  • Posts: 15949
  • Joined: 24 Jun 2009

Posted 22 October 2019 - 04:09 PM

James:

 

As others have suggested, the CG-4 is the apparent choice.  Looking at your equipment list, i see you have a Skywatcher 6 inch F/8 Dob.  I'm not sure what you're hoping to gain with this 4 inc F/10 achromatic refractor? 

 

Jon

Hey!  He gains 

 

2.75 degrees refractor versus 2.3 degrees on the Newt!  (assuming both have 2" focusers and that he has a 40 mm 70 degree eyepiece that will cost as much as either scope)

 

-and- 

 

Fully illuminated!  (thereby joining the Illuminati)

 

Not to mention the prestige of owning a refractor.  No tripod!  can be used pirate style!  

 

what's not to like????

 

and more to the point for $230 he gets to play with a refractor.   Ooodles of learning experience for not much outlay.  Very good way to understand how completely different the mechanics of using one of these differs from the dob.   Including why it is that everyone here is going on about the mount.  Someone who has only had a dob hasn't really been exposed to serious instability issues.  

 

Actually the table top scope in my signature is no joke.  That was my first scope after 25 years of not doing astro.  I learned that I needed a good optic and a better mount.  I got a c8 on a CG5 (the old ones on extruded aluminum legs) and learned I needed a better mount.  

 

Sometimes you have to see this stuff for yourself before you "believe" it.  

 

Greg N


  • noisejammer and Terra Nova like this

#21 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 79602
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 22 October 2019 - 05:06 PM

and more to the point for $230 he gets to play with a refractor.   Ooodles of learning experience for not much outlay.

 

 

Realistically, we're talking more like $500 with a mount.  My question was meant for James, wondering what he why he was interested in this scope.

 

Jon


  • Binojunky likes this

#22 gnowellsct

gnowellsct

    Hubble

  • *****
  • Posts: 15949
  • Joined: 24 Jun 2009

Posted 22 October 2019 - 05:25 PM

Realistically, we're talking more like $500 with a mount.  My question was meant for James, wondering what he why he was interested in this scope.

 

Jon

Hey, public post is for all to see.  Realistically, Jon, if a person is getting into refractor ownership and has to hesitate between $250 and $500 with the mount, it's probably not a game s/he should be in. 

 

It's not always about the biggest aperture for a view.  Sometimes people want to try different scopes.  

 

GN



#23 Jond105

Jond105

    Skylab

  • *****
  • Moderators
  • Posts: 4451
  • Joined: 19 Feb 2018
  • Loc: Detroit

Posted 22 October 2019 - 05:29 PM

At the end of the day the refractor and mount will make a good combo and good step into refractor world. The upside is, the refractor can always stay or be upgraded to an ED type scope, and the mount could be a lifetime investment never needing to

upgrade. 


  • gnowellsct likes this

#24 gnowellsct

gnowellsct

    Hubble

  • *****
  • Posts: 15949
  • Joined: 24 Jun 2009

Posted 22 October 2019 - 05:39 PM

At the end of the day the refractor and mount will make a good combo and good step into refractor world. The upside is, the refractor can always stay or be upgraded to an ED type scope, and the mount could be a lifetime investment never needing to

upgrade. 

That's true.....some may wonder whether $300 mounts/tripods fall into the lifetime investment category, but I know a number of people here whose observing skills I respect who use such budget items over the long term. 

 

I'll have to check out some of these budget mount/tripod next time I'm at NEAF.  I don't think Vixen has been going to NEAF, which is what I would look for.  So I either have to find a vendor with portamount and some kind of refractor on display or be on the alert for the porta-mount equivalents.  It requires a certain discipline to do that, there's a lot of distracting $$$ gear at NEAF that is seldom even talked about here, let alone seen in the usual venues (star parties etc.).  For example, everyone has *heard* about the Losmandy Titan, but how many have seen one at a star party?  Everyone has *heard* about the TEC 140, but how many have seen one at a star party (I have, once, in a star party far from my local base).      

 

Greg N


  • Jond105 likes this

#25 Don Taylor

Don Taylor

    Apollo

  • *****
  • Posts: 1117
  • Joined: 12 Jul 2009
  • Loc: Broken Arrow (Tulsa Area) Oklahoma

Posted 22 October 2019 - 06:21 PM

 Well, you could just buy the Omni & CG-4 for $437 including shipping:  https://www.highpoin...telescope-21088


  • tony_spina, gnowellsct, Terra Nova and 3 others like this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics