Barlow Lens Information/Advice

[kz1bob]

Hi All,

I need to get a new 2x Barlow lens and looking online prices vary from a few quid to several hundred quid. While I am happy to go on a research tour of the internet, I thought I would get more mileage out of this group. :-)

My telescope is a Bresser AR-102S/600, is there anything in particular in a Barlow that I should be looking for? I am just getting into AP, but do like to just look at things every now and again.

Thanks in advance for any advice.

James

 

[Stub Mandrel]

I have one of these, they seem to be considered to mark the price-point where Barlows become worthwhile:

https://www.firstlightoptics.com/barlows/celestron-2x-universal-125-barlow.html

Probably cheap enough and not weep if it doesn't suit you, but I get on OK with mine.

 

Edit: extra benefits you can fit a camera t-mount adaptor to it, use it without the lens as a camera mount. One oddity is that if you need to fit a filter it has to go between the body and the lens, which slightly increases its power.

[Louis D]

I prefer several older, harder to find Japanese made barlows such as the Meade 140 and the Orion Deluxe.  However, the Taiwanese made GSO 2x achromatic barlow lens available in Europe here gets good reviews for its price.  It might be available in the UK as well.  It seems to be getting hard to find.  Many places have sold out of it.

[Ricochet]

The one linked to by Stub Mandrel seems to me to be a perfectly reasonable Barlow as long as you don't need to screw a filter to the end of it and is often available on astroboot under the Skywatcher brand for £15. If you want to spend more than that then I would look at either the Antares Twist Lock Barlow for ease of use or buy a focal extender from Televue or Explore Scientific.

[John]

The best "budget" barlow that I've used is the GSO / Revelation 2.5x:

http://www.telescopehouse.com/revelation-astro-2-5x-barlow-lens.html

I reckon it's closer to 2.2x in reality though.

The 2x GSO one mentioned above is the same item that is sold as the Celestron Omni barlow and I didn't find it more than moderately good.

If you can find a used Celestron Ultima 2x or Orion Shorty Plus 2x (both the same item and the "Plus" is significant) for under £50 then those are well worth considering because they have excellent Japanese optics. Their actual amplification is closer to 2.2x though.

 

[Mak the Night]

+1 for the budget GSO/Revelation 2.5x Barlow. I have the TS Optics version. I've got a feeling that John's right about it being more like 2.2x or 2.25x though.

The Celestron X-Cel is very well made and a useful short Barlow. The safety undercut is shallow and isn't much of a problem extracting from anything with a compression ring. The Barlow is solidly built.

This Omegon 2x 'Short Barlow' (below) is the nearest in quality to my TeleVue Barlows to look through. Its build quality is also quite good and has a filter thread. It is originally made by Barsta (BST) and reputedly the apochromatic glass element is Japanese. TS Optics and others distribute the same Barlow but often cheaper than Omegon (if only I'd known at the time lol).

[LukeSkywatcher]

I have a Revelation 1.5-2X. I ordered an Antares 2x, but the revelation arrived instead. Cant say it gets any use

[wookie1965]

On 18/08/2016 at 15:10, Mak the Night said:

+1 for the budget GSO/Revelation 2.5x Barlow. I have the TS Optics version. I've got a feeling that John's right about it being more like 2.2x or 2.25x though.

The Celestron X-Cel is very well made and a useful short Barlow. The safety undercut is shallow and isn't much of a problem extracting from anything with a compression ring. The Barlow is solidly built.

This Omegon 2x 'Short Barlow' (below) is the nearest in quality to my TeleVue Barlows to look through. Its build quality is also quite good and has a filter thread. It is originally made by Barsta (BST) and reputedly the apochromatic glass element is Japanese. TS Optics and others distribute the same Barlow but often cheaper than Omegon (if only I'd known at the time lol). Is this the same one please https://www.amazon.co.uk/TS-Optics-Achromatic-Barlow-Multi-Coated-TSB21/dp/B004ORS5W0

 

[Mak the Night]

9 hours ago, wookie1965 said:

 

No, I think that's the GSO achromatic. This is the TS Optics branded Barsta (BST) apochromatic.

[wookie1965]

9 hours ago, Mak the Night said:

No, I think that's the GSO achromatic. This is the TS Optics branded Barsta (BST) apochromatic.

Thank you for that I was considering this one http://www.ebay.co.uk/itm/BST-Starguider-1-25-Short-2x-Apochromatic-3-element-Barlow-lens-/381681330193?hash=item58ddfae811:g:roAAAOSwNuxXbQXw

[Mak the Night]

53 minutes ago, wookie1965 said:

Thank you for that I was considering this one http://www.ebay.co.uk/itm/BST-Starguider-1-25-Short-2x-Apochromatic-3-element-Barlow-lens-/381681330193?hash=item58ddfae811:g:roAAAOSwNuxXbQXw

Yes, I'm convinced it's the same Barsta (BST) 2x apochromatic short Barlow. They're quite high quality 'shorties' IMO.