Is it worth buying a x2 Barlow - Definitely

[Sirius Starwatcher]

Just been out for the last hour with the Dob and the moon. Decided to use the barlow on each of my EP.s

Pushed my luck and Barlowed the BST 5mm. WOW. ( Mind you you have to move the dob pretty quickly.)

So if your in the market for a Barlow lense don't hesitate. It doubles your EP collection and with the right target and clear skies it works a treat .

Will give it a couple of hours and out again I hope. I have a date with Jupiter after 9.45 pm.

[spaceboy]

You may find the moon can handle x480 magnification but I doubt you will have as much success with Jupiter. I agree that barlows can be handy to have most notably for webcam imaging and grab and go setups with zoom eyepieces.

[John]

Maxing out the power is fun on the Moon. When you want to study the fine details though dropping back to 200x - 250x will show a sharper view, unless tonight is one of those once-a-year nights when you can throw everything at it !

With my 12" dob I find I can resolve the finest lunar details at 265x - 318x, assuming decent seeing. I can push to 400x, 500x or even 600x and it's great fun but the tiny craterlets and fine rilles are nowhere near as easy to discern.

[swamp thing]

Love barlows me. They allow you to keep a high standard of eyepiece f lengths from half the number of eyepieces. Anything that saves a few bob has gotta be a winner IMO 

[Pete Presland]

I also love barlows! When imaging with my PST it is rarely done with out one.

[Charic]

Gary....my Skywatcher Barlow has a removable lens cell, so I can call up either 2x with Barlow tube   or 1.6x without tube. (approximate 1.6x ). It makes a difference, and more often than not, I just use the lens at 1.6x ( fitted directly to the eyepiece in use )

[Steve789]

Is there any point in getting a 3x barlow? I've got a 2x barlow (skywatcher) and an extension tube which must bring it up to about 3x or more. I was wondering if I'd get a better image through a dedicated 3x Barlow or if I should just put the money towards a better quality 2x Barlow.

[happy-kat]

That suggests I could add a tube to my AE 1.6x barlow :-)

[phoobar]

I also love my barlow, the ES MV 16mm and 9mm plossl are my favourites used most in it.

[hgjevans]

Just been out for the last hour with the Dob and the moon. Decided to use the barlow on each of my EP.s

Pushed my luck and Barlowed the BST 5mm. WOW. ( Mind you you have to move the dob pretty quickly.)

Snap - in every detail, bar the Dob (my scope is on an EQ). But yes, the 5mm BST (which I only acquired last week, and hadn't yet had good enough conditions for it to show its mettle) performed wonderfully, and Barlowed up far better than I was expecting - at least for the brief spell I had with it before the cloud (which had been patchy all evening) finally closed up and brought the session to an end. 

Having said that, if I'm completely honest, the most memorable views were with the un-Barlowed 5mm - spectacular! I'll never complain about the moon in my skies again.

[Sirius Starwatcher]

Gary....my Skywatcher Barlow has a removable lens cell, so I can call up either 2x with Barlow tube   or 1.6x without tube. (approximate 1.6x ). It makes a difference, and more often than not, I just use the lens at 1.6x ( fitted directly to the eyepiece in use )

Thanks Charic I will need to look into this. VMT

[Sirius Starwatcher]

Snap - in every detail, bar the Dob (my scope is on an EQ). But yes, the 5mm BST (which I only acquired last week, and hadn't yet had good enough conditions for it to show its mettle) performed wonderfully, and Barlowed up far better than I was expecting - at least for the brief spell I had with it before the cloud (which had been patchy all evening) finally closed up and brought the session to an end. 

Having said that, if I'm completely honest, the most memorable views were with the un-Barlowed 5mm - spectacular! I'll never complain about the moon in my skies again.

Clearly. Great minds think alike!

[Dave In Vermont]

I would only add that if you buy a Barlow, get the best one available, such as a TeleVue. There is nothing worse than a low quality Barlow which can dim your view and add distortion. The best Barlow there is is one that vanishes in the optical-pathway, and seems to just blend into the eyepiece. Most would agree that TeleVue is a strong candidate for doing this. I'm sure someone will recommend another or too.

As for 3X Barlows, I have one but just about never use it. The 2X is my workhorse.

Clear & Sharp Skies,

Dave

[Sirius Starwatcher]

Just been out for the last hour with the Dob and the moon. Decided to use the barlow on each of my EP.s

Pushed my luck and Barlowed the BST 5mm. WOW. ( Mind you you have to move the dob pretty quickly.)

So if your in the market for a Barlow lense don't hesitate. It doubles your EP collection and with the right target and clear skies it works a treat .

Will give it a couple of hours and out again I hope. I have a date with Jupiter after 9.45 pm.

Well had my date with Jupiter as she was in a better position for me by 2200. Again Barlowed as much as I could. best I could get down to was 12mm BST. Which is what I expected to get. Must admit I,struggled to notice the difference between my 25 mm Barlowed BST and my un Barlowed WO 6mm. All in all a nice quiet viewing evening with a little more learnt. Don't you just love this hobby

[NotSoSuperNova]

I was a bit scared of the humble Barlow due to the 'more glass = more lost' argument. I won't lie and say i use my Barlow all the time, I tend to concentrate on deep space objects, but having one available is always handy. 

[S.A.M]

Yes, it doubles the number of available eye pieces you have but will lose some quality of the subject viewed.

Peter

[FLO]

Yes, it doubles the number of available eye pieces you have but will lose some quality of the subject viewed.

That is certainly what most people believe but there is more to consider

A barlow lens fits in-between the telescope and eyepiece and doubles (more or less, depending on the barlow) the eyepiece magnification. Our American cousins would say it is a ‘no brainer’ because in effect it doubles the number of eyepieces in your collection (if you own three eyepieces adding a barlow provides six magnifications). However, if, say, you have a 20mm eyepiece a 2x barlow will essentially make it a 10mm. Which is great, unless you already own a 10mm… 

Regarding the affect on quality, a modern barlow will often improve the performance of an eyepiece because it can reduce astigmatism at the edge of the field. (The belief that barlows reduce performance probably comes from people barlowing a high magnification eyepiece resulting in a magnification higher than the telescope, or our atmosphere, can support). 

Another benefit of using a barlow - it enables you to use a longer focal length eyepiece (with it's longer eye-relief) for high magnification observing. This can be a significant benefit to those who wear glasses when observing. 

HTH, 

Steve

[Sirius Starwatcher]

That is certainly what most people believe but there is more to consider

A barlow lens fits in-between the telescope and eyepiece and doubles (more or less, depending on the barlow) the eyepiece magnification. Our American cousins would say it is a ‘no brainer’ because in effect it doubles the number of eyepieces in your collection (if you own three eyepieces adding a barlow provides six magnifications). However, if, say, you have a 20mm eyepiece a barlow will essentially make it a 10mm. Which is great, unless you already own a 10mm… 

Regarding the affect on quality, a modern barlow will often improve the performance of an eyepiece because it can reduce astigmatism at the edge of the field. (The belief that barlows reduce performance probably comes from people barlowing a high magnification eyepiece resulting in a magnification higher than the telescope, or our atmosphere, can support). 

Another benefit of using a barlow - it enables you to use a longer focal length eyepiece (with it's longer eye-relief) for high magnification observing. This can be a significant benefit to those who wear glasses when observing. 

HTH, 

Steve

Thanks for the in depth info, it really helps. Now where are the SW St 120 please FLO !

[FLO]

Thanks for the in depth info, it really helps. Now where are the SW St 120 please FLO !

We don't know. We hope they are enroute somewhere between China and the UK. The importers say they will email us an ETA as soon as they are able. If you haven't already please email us so we can keep you updated (I cannot tell who you are from your username). 

HTH, 

Steve

[LittleSkink]

good thread - and thanks Flo, learnt something there too

fwiw Astroboot have listed a nice 2 lens 1.5x / 2x Revelation Barlow for £15 (under Misc not in Astro section)

I got one by accident to upgrade the cheap Skywatcher one that came with our scope (tried to order some stuff on their site and 1 item went out of stock over the weekend so agreed to have this in the order instead). The Revelation one is really nicely made and works a treat - though maybe not loads better than the SW one

[bingevader]

That is certainly what most people believe but there is more to consider

A barlow lens fits in-between the telescope and eyepiece and doubles (more or less, depending on the barlow) the eyepiece magnification. Our American cousins would say it is a ‘no brainer’ because in effect it doubles the number of eyepieces in your collection (if you own three eyepieces adding a barlow provides six magnifications). However, if, say, you have a 20mm eyepiece a 2x barlow will essentially make it a 10mm. Which is great, unless you already own a 10mm… 

Regarding the affect on quality, a modern barlow will often improve the performance of an eyepiece because it can reduce astigmatism at the edge of the field. (The belief that barlows reduce performance probably comes from people barlowing a high magnification eyepiece resulting in a magnification higher than the telescope, or our atmosphere, can support). 

Another benefit of using a barlow - it enables you to use a longer focal length eyepiece (with it's longer eye-relief) for high magnification observing. This can be a significant benefit to those who wear glasses when observing. 

HTH, 

Steve

Steve, I felt your pain!

No! Don't buy a barlow, buy lots of individual eyepieces from FLO!

Yes! Do buy a barlow, they're great, from FLO!

HTH you buy stuff from FLO!

Thanks for the Christmas choc btw.

On topic: As I know I've said before, they're also great for taking on holiday, cuts down on the number of EPs you need.

[ollypenrice]

I'm a bit of a doubting Thomas on all this and was relieved to read Steve's FLO post. Whether or not it doubles your EP collection depends on your EP collection. Personally I don't feel much need for gazillions of EPs and really only use two in the big Dob, a 13 Ethos and a 26 Nagler. At shorter focal lengths on other scopes I do use shorter FL EPs to get the power but, quite honestly, I could live with just three EPs, though they'd be good ones. I can see that double star splitters might want more but for looking at DSOs I'd just add our 4.8 Nagler (very old) to the two previous ones and I'm done. I think that looking at the object beats looking at what a change of EP brings to the object.

If you have, say, 5, 10, 20 and 30mm, what do you gain from a Barlow? After a few years mine fell into disuse and I'm nt even sure I could find it now!

Olly

[FLO]

If you have, say, 5, 10, 20 and 30mm, what do you gain from a Barlow? 

Not a lot

I know you know this Olly but (for those who might not know) if you add a 2x barlow the 5mm would become a 2.5mm (too high a magnification for most telescopes). The 10mm would become 5mm so duplicate the existing 5mm (though you might appreciate the longer eye-relief of the barlowed 10mm) and the 20mm would become 10mm so duplicate the existing 10mm. The 30mm would become a 15mm so you would achieve one additional useful magnification. Personally I'd rather buy another eyepiece. 

But, if you have a 5mm, 14mm, 20mm & 32mm a barlow would add four extra magnifications so your effective eyepiece set would be 2.5mm, 5mm, 7mm, 10mm, 14mm, 16mm, 20mm & 32mm. The 2.5mm would result in a magnification too high for most telescopes but the remaining three will be useful so in this instance a barlow makes a lot of sense. 

HTH, 

Steve

[Sirius Starwatcher]

So 22 posts and still counting. You have to,ask the question. Is it worth buying a x 2 barlow. Or has somebody asked this question before ? . lol

[sunka]

In my experience, barlow is problematic, but I did go into extremes - Antares 1.25" 5x barlow on 8" f/5 skywatcher. I did see magnificent photos with similar scopes and this barlow but my views through 25mm eye piece & photos are not sharp (and believe me, I spent lots of time focusing even with Bahtinov mask when recording on DSLR). Here are sample photos

Stacked Saturn:

Monday stacked Jupiter (seeing was excellent but as I said, image is not sharp)

For comparison single frame of Jupiter with moons from yesterday, no barlow - seeing was bad and it is still sharper:

That is my experience, but of course I did not test good quality 2x barlow...