Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

Danny83uk

Advice on which Barlow to upgrade to.

Recommended Posts

Hi all, Im currently using Celestron 2x Universal for my imaging but would like to tighten up the quality now ive got to grips with exposure times,ISO  and stacking. My usual stockists have 2 different variants and just gathering opinions.

They are BST Starguider 1.25 Short 2x and Celestron X-Cel Barlow Is there a better one over the other? I'll probably be getting the 3x of the same model at a later date or at christmas if ive been a good boy. Also would 5x Meade Series 5000 TeleXtender be difficult to use  for planetry photography?

Thanks

Danny

Share this post


Link to post
Share on other sites

If you can get a used Tele Vue Powermate 2.5x then you won't need to upgrade again.

They can be had for around £120 on UK Astro Buy & Sell.

A less expensive but similarly excellent alternative is the Explore Scientific 2x Focal Extender.

Either would be a noticable step up over your current barlow wheras I suspect the others you mention might not be such a noticable improvement ?

 

Edited by John
  • Like 1

Share this post


Link to post
Share on other sites

There is a brand new Televue 2x Barlow on ABS at the moment, good price too, I have one and they are superb quality... :)

  • Like 1

Share this post


Link to post
Share on other sites

I've said it before, but it bears repeating: The best Barlow is one that is invisible in the optical-pathway. This means that it lends no internal reflections, no distortions. It simply adds magnification to the view. There's nothing worse than a Barlow which imparts, and magnifies, it's own short-comings in the glass itself.

I'll 2nd. John's suggestion of a TeleVue® 2.5X PowerMate, or any other TV Barlow. There are other top-end Barlow's made, but the TeleVue® are the one's I have and use. And though TV is known to be the most expensive products out there, they really aren't that much more £££'s - considering that it will be the last one you'll ever buy. You can't go up from the top.

Dave

Edited by Dave In Vermont
sp.
  • Like 2

Share this post


Link to post
Share on other sites

Another contender might be a second-hand Celestron Ultima x2 Barlow, now out of production. Not as good as Televue - but quite close for less money and possibly the best Barlow made/marketed by Celestron. I've heard it is the same as the Orion Shorty Plus, so perhaps another second-hand alternative.

Share this post


Link to post
Share on other sites
20 hours ago, John said:

If you can get a used Tele Vue Powermate 2.5x then you won't need to upgrade again.

They can be had for around £120 on UK Astro Buy & Sell.

A less expensive but similarly excellent alternative is the Explore Scientific 2x Focal Extender.

Either would be a noticable step up over your current barlow wheras I suspect the others you mention might not be such a noticable improvement ?

 

Please excuse my ignorance but why the 2.5x over a 2x and 3x seperately to give you more focusing options (expense being one obviously) Is This the one you mean?

18 hours ago, Dave In Vermont said:

I've said it before, but it bears repeating: The best Barlow is one that is invisible in the optical-pathway. This means that it lends no internal reflections, no distortions. It simply adds magnification to the view. There's nothing worse than a Barlow which imparts, and magnifies, it's own short-comings in the glass itself.

I'll 2nd. John's suggestion of a TeleVue® 2.5X PowerMate, or any other TV Barlow. There are other top-end Barlow's made, but the TeleVue® are the one's I have and use. And though TV is known to be the most expensive products out there, they really aren't that much more £££'s - considering that it will be the last one you'll ever buy. You can't go up from the top.

Dave

Same question really on the 2.5 over 2,3x. I like the idea of its the last one ill buy.

 

Any opinions on the 5x?

Share this post


Link to post
Share on other sites

The TV PowerMates are not a 'true' Barlow, but a different design - technically speaking. They provide an excellent view, as do the TV Barlows of 2X and 3X. I realize the first impulse of new astronomy fans is to throw extreme magnification in hopes of getting views like the Hubble Space Telescope. But for most applications, using 5X will not be practical due to mitigating factors - like 'seeing' conditions. Remember - you'd be magnifying everything by a factor of 5X. Including atmospheric disturbances. You'd be better off trying a shorter focal-length eyepiece.

If you buy a top-drawer Barlow, I think you'd get much more mileage for your money with a 2X or 3X Barlow, or a 2.5X PowerMate.

Best wishes,

Dave

Share this post


Link to post
Share on other sites

Another vote for the Power mate (and indeed the 2x TV Barlow). As Dave said, they just disappear in use. I also have the well-regarded Orion Shorty Plus 2x ( useful in not adding too much weight/length to my small scopes) but it has never seemed *quite* as invisible as the Tele Vues - tho this is utterly subjective as I've never directly compared them at the eyepiece on the same night, so seeing etc could be a factor!

Agree with John tho - I'll never sell the Power mate unless something substantial is at stake :)

Share this post


Link to post
Share on other sites

Although I consider the TV 3x Barlow probably the best of its kind, if you need a shorter 3x the Celestron X-Cel is excellent quality.

3x comparison.jpg

Share this post


Link to post
Share on other sites
48 minutes ago, Dave In Vermont said:

The TV PowerMates are not a 'true' Barlow, but a different design - technically speaking. They provide an excellent view, as do the TV Barlows of 2X and 3X. I realize the first impulse of new astronomy fans is to throw extreme magnification in hopes of getting views like the Hubble Space Telescope. But for most applications, using 5X will not be practical due to mitigating factors - like 'seeing' conditions. Remember - you'd be magnifying everything by a factor of 5X. Including atmospheric disturbances. You'd be better off trying a shorter focal-length eyepiece.

If you buy a top-drawer Barlow, I think you'd get much more mileage for your money with a 2X or 3X Barlow, or a 2.5X PowerMate.

Best wishes,

Dave

Not to mension the problems keeping the object in focus and view. It would be used for imaging but I was moving away from it for that reason originally but just needed to clarify. Could you elaborate more on its difference? Does this difference make it more suitable for imaging over viewing?

 

Share this post


Link to post
Share on other sites
7 minutes ago, Danny83uk said:

Not to mension the problems keeping the object in focus and view. It would be used for imaging but I was moving away from it for that reason originally but just needed to clarify. Could you elaborate more on its difference? Does this difference make it more suitable for imaging over viewing?

 

I've found that Powermates work excellently for visual observing. They literally "get out of the way" leaving just the amplified magnification without the optical effects that a barlow (even an excellent one) adds in terms of changing the focus point, extending the eye relief and sometimes vignetting the field.

I'm not an imager myself but I know that Powermates are very popular with imagers as well.

 

Share this post


Link to post
Share on other sites
1 hour ago, Mak the Night said:

Although I consider the TV 3x Barlow probably the best of its kind, if you need a shorter 3x the Celestron X-Cel is excellent quality.

3x comparison.jpg

How do you think the longer Barlow would cope with a 409g dslr body attached to it? It is a relatively light body, which is why I picked it. But curious. 

Share this post


Link to post
Share on other sites
1 hour ago, Danny83uk said:

How do you think the longer Barlow would cope with a 409g dslr body attached to it? It is a relatively light body, which is why I picked it. But curious. 

The TV 3x is 13cm tall and weighs about 181 grammes. The taller the Barlow the more potential for it to rotate the diagonal.

Share this post


Link to post
Share on other sites

I don't image but for my needs I have the  Sky-watcher 2x deluxe, because it had an adapter/extension for dslr use and removable cell,   if/when needed and I keep forgetting  the Meade #140 2x Apochromatic Barlow Lens, so need to refresh my memory and test that again when the weather improves?
I hear so many folk praise the Powermate ( never had the chance to try one) but as john so rightly points out, quite often when one 'upgrades'  there "might not be such a noticable improvement ?"[sic] to what you already have.
By testing yourself, only you can tell if one is better than another. You have the option to return goods if you order online, keep returning until you find what suits you best?

Edited by Charic

Share this post


Link to post
Share on other sites

One trick I use for weight-loads that can cause things to rotate or slip, where the interface is a soft-alloy and a brass-ring such as is found on compression-bands for telescope parts, adapters, etc. - is to roughen the surface the softer brass will be trying to hold in place. It may seem similar to desecrating a religiious-icon (or TeleVue® Barlow), but by using a very hard file - file away on the alloy-barrel of the Barlow (in this case) to create pits & valleys for the compression-ring to bite into firmly.

I have a poorly designed alt.az-mount that was supposed to hold 10lbs. But wouldn't even hold 2lbs. So the outfit selling these dropped the price by 2/3rds. I used the above method to 'repair' it. Now it holds better than 10lbs.

Call it physics?

Dave

Share this post


Link to post
Share on other sites
On 15/11/2016 at 04:28, Dave In Vermont said:

One trick I use for weight-loads that can cause things to rotate or slip, where the interface is a soft-alloy and a brass-ring such as is found on compression-bands for telescope parts, adapters, etc. - is to roughen the surface the softer brass will be trying to hold in place. It may seem similar to desecrating a religiious-icon (or TeleVue® Barlow), but by using a very hard file - file away on the alloy-barrel of the Barlow (in this case) to create pits & valleys for the compression-ring to bite into firmly.

I have a poorly designed alt.az-mount that was supposed to hold 10lbs. But wouldn't even hold 2lbs. So the outfit selling these dropped the price by 2/3rds. I used the above method to 'repair' it. Now it holds better than 10lbs.

Call it physics?

Dave

I dont think ill be willing to do that. but i see where your going. Im more inclined to rotate my scope so its either hanging directly down or pointing up to remove any bend in the optics.

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By Corpze
      Hi, i have made a video where i show a coople of eyepieces that i use and like, and also show how a barlow works, compared to the "Powermate" from Televue. And how is the FOV affected when changing the magnification with different eyepieces?

      Feel free to comment and give me feedback - I hope you like the video!
      /Daniel
       
       
    • By Zermelo
      I picked up a Celestron Omni last year quite cheaply and had originally been using that with stock eyepieces, which was fine.
      Since then I've bought a couple of BST Starguiders and a Hyperflex zoom, and I'm now wondering if I'd notice any difference with a better barlow (this is now being used on an F/5 150mm Newtonian). Otherwise, the pennies can be directed elsewhere.
      I'd not considered it before as the next rung up seemed to be around the £90-£100 mark, which seemed out of line with the rest of the spend. But I've seen some positive reviews of 3-element models in the region of £35-£40.
      In particular, I've read good things about the Revelation/GSO Astro 2.5x (though apparently closer to 2.2x) and the Baader Classic Q 2.25x.
      - does anyone have experience with both of these, and have a preference?
      - would I notice any significant difference with either, compared with the Omni?
      - I read somewhere that the Baader in particular required focussing the tube into the OTA to an extent that caused some image degradation. Obviously I'd want to avoid this if true, so is this a feature of the Baader, or of both, or of all (shorter?) barlows? (to be honest, I'd not thought to see whether this was happening with the Omni, I'll try to remember to check, if this weather ever breaks).
      Thanks in advance.
    • By LondonSi72
      Hi SGL,
      My lovely wife bought me a SW Explorer 130 with the basic RA drive for my 40th birthday 8 years ago, and I've enjoyed using it on and off ever since.  I've started getting more into it - it's a great beginner scope, but I'm - like lots of others on this forum - looking at upgrading.  One of the things I found tricky with the scope was getting the focus just right at high magnification (I'm sure that's kind of obvious!).  It does wobble quite a bit on the EQ2 mount when focusing.  I get pretty good - if small - views of Jupiter, Saturn, (the Moon, of course) and have had hints of seeing some DSOs.
      I bought a 8mm BST Starguider, and it's a great improvement on the standard 10mm that comes with the scope, but if I push the scope by adding the 2x Barlow and the 8mm it's a blur and the focus seems to keep missing the sweet spot.  I saw a post elsewhere on this forum by MakTheNight, (looks like they've left now - last post was 2 years ago) who added a Baader Helical Focuser that attached directly to the T-thread on the focusing apparatus on the SW. Link to that post is below. I got one and it is indeed a great improvement on fine tuning - the problem is I can't use it with the Barlow as the helical focuser is about an inch long and the focuser can't move far enough into the scope to focus with the Barlow and any of my eyepieces (the 8mm BST, or the 10 or 25mm standard eyepieces)
      .
      Clearly MakTheNight managed to get their setup to work with some specific eyepieces (a Luminos 10mm and 32mm Plossl) and a specific Barlow, so I tried looking up how I could work out what combination of eyepieces and Barlow would work, rather than randomly buying kit and having to return it because it won't work with my scope, but I haven't found anything useful yet.  So I thought I'd take the plunge and ask here

      Can anyone help me figure out how I can calculate what combinations of eyepiece and Barlow would work with this setup?  I'm also looking at upgrading the OTA and mount to a 200P and EQ5 at some point, so ideally would have a combination that could work with that too - the focal length and mirror is quite different - 1000mm on the 200P parabolic vs 900mm spherical on the 130.
       
      Many thanks!
      Simon
       
       
    • By StarGazingSiouxsie
      Hi  
      Tonight I was looking at Jupiter and got some nice views with a range of eyepeices. The best image detail wise and for clarity of image was a 15mm, which on my 8" Evolution gives me appx 135X 
      I tried using my Televue 2X Barlow which normally works fine. I can't remember exactly which eyepiece this happened with, maybe the 15mm or a 9mm, but when I used the barlow the planetary image would soon disappear out of the eyepiece. The mount seemed to otherwise be tracking OK although notice the planets seem to move out of the eyepiece view after a while. So did I have too much magnification with the Barlow? I think I did manage to get focus, the image just wouldn't stay put.
      Thanks for any insights or advice 
       
      Siouxsie 
    • By Ryaen
      Hi, I am pretty much new in Astronomy. Recently I have bought Meade Polaris 127mm telescope. The Barlow(2x) which Meade has provided is pretty basic. It gives pretty blurry view.
      I have read few blogs and get to know that for 127mm, 2x-3x magnification is more than enough. Now I’m confused in its specs(element in it).
      Wondering which one I choose, 2.5x Barlow 3 element or 2x Barlow with 2 element to get clear and crisp viewing.
      Ryaen
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.