23 replies to this topic

[25585]

What are your favourite Barlow+eyepiece combinations? What do you use them on?

[Jethro7]

Hello 25575,

In my case it is my Leica ASPH vari 8.8X -17.9X Zoom and a Tele Vue 2X Powermate. This combination has replaced all of my eyepieces below 20mm. 

 

HAPPY SKIES AND KEEP LOOKING UP Jethro

 

P.S. To be honest, I also like using my Tak 1.5X Focal Extender as well.

Edited by Jethro7, 21 April 2025 - 11:10 AM.

[Olimad]

My favorite Barlow is the APM 2.7x Coma Correcting model. I use it with a 32mm Plössl (at a reduced magnification factor) to get the cleanest and widest true field of view I can, as well as with various orthos and Plössls.

 

I get pretty nice results that way, reaching magnifications from 1/4D to 2.4D depending on the target and the dark of the Sky where I am.

 

I now have a 5x focal extender. I’ll have to see how my system performs at f/20 and f/11 at the same magnifications—of course, using different focal lengths from the same line of orthos or Plössls.

 

I have read that some plössls or orthos line need bigger f/ratio to truly express themselves.

[russell23]

20mm XW with 2.4x Dakin barlow.

[Jon Isaacs]

My favorite combinations are the 1.25 inch TeleVue 2x Barlow with the type 6 Naglers.  I mostly use the 5 mm and 3.5 mm for high magnifications, mostly close doubles, the 3.5mm +Barlow is 820x in my 10 inch. 

 

I occasionally use longer focal length type 6s with the Barlow to fill in the gaps. 

 

One advantage of a Barlow is that it can provide a mild but significant zoom effect, about 10%.  By pulling the eyepiece back, the 3.5 mm combo covers 820x - 900x. 

 

Jon

Edited by Jon Isaacs, 21 April 2025 - 11:25 AM.

[vtornado]

Meade Super Plossl 12.5mm 2x long barlow

[areyoukiddingme]

Also Leica, but I use it typically with a Nikon 1.6 (which works as a 1.8x) in my 12.5" F5, or with a 2.5x Powermate, which is a better match for my 8" reflector.

[Albie]

What are your favourite Barlow+eyepiece combinations? What do you use them on?

What is your favourite ?  With my 10" f/4.7 dob  my favourite would be the only one I own , the Meade 5000 1.25" 2X TeleXtender . I have only one eyepiece that I will use it with , the Pentax XW 7mm . Who knows maybe I will end up getting rid of the TeleXtender and buying a Pentax XW 3.5mm .

Edited by Albie, 21 April 2025 - 01:29 PM.

[sevenofnine]

The ES 2x FE & AT 12/60 Starguider ED works well for me in my 8" f/5.9 Dob. 

Edited by sevenofnine, 21 April 2025 - 05:19 PM.

[bobhen]

I use my Tele Vue 2x Barlow and my University Optics 2.8x Klee Barlow with my Tele Vue Delites to fill in some magnification gaps between single eyepieces. And if an eyepiece is pulled up slightly in a Barlow one gets a mild zoon effect to further fill in magnification ranges.

 

I use Barlow/eyepieces combinations with my Takahashi TSA 120 and Takahashi FS-100DF refractors for observing the moon and planets and with my Lunt 100 Ha solar scope for observing the sun.

 

Before I moved to Delites, a few favorite uses from the past were the above Barlows with Orthos and Brandons. The Barlows gave the eyepieces more ER, which made observing more comfortable.

 

I don't use Barlows for deep sky observing.

 

Bob

Edited by bobhen, 21 April 2025 - 01:59 PM.

[balcon3]

My favorite pair was Morpheus 9mm with a Baader VIP Modular Barlow at 2x or 2.6x for viewing planets. But then I started using a Binoviewer (with 2.6x GPC) for planets and I hardly use a Barlow anymore.

[PJ Anway]

What are your favourite Barlow+eyepiece combinations? What do you use them on?

My favorite combination is a Tele Vue 7mm Nagler circle "NJ" eyepiece in a Vernonscope Dakin 2X barlow. With my 4.3" refractor, it yields 176X for use on the planets.

[scout]

I often use my 2.2x Ultima Barlow with my 4mm AT 82° UWA on tight double stars. It gives me 396x in my 102mm refractor and 240x in my 72mm refractor. The two apos can easily support such high powers on double stars, with beautiful Airy disks and rings when the seeing is good.

[GrassLakeRon]

My xwa's and gso 2" Barlow. My gso plossls and gso 2.5 Barlow.

[mountain monk]

Nikon 1.6x Barlow, Televue 2x (1.25) Barlow, and Televue 2.5x Powermate with 3mm, 5mm, 7mm, 10mm Pentax and 6mm and 8mm Ethos. But my seeing rarely permits me to go into such magnifications, often 200x is the limit, occasionally I will reach 300-400x—Hyperdrive. The most common scope used is my NP-101, which often needs them; my Tak DZ uses them less, and my 11” Dob, very, very, rarely. In the Dob, the Ethos 6mm with the Televue 2x is 480x, with the Powermare, 602x…wheeee.
 

Dark, clear, calm skies.

 

Jack

[Matthew Trail]

Because of my eyepiece set, I find I get a bit more use out of my TV 1.8 and Ultima 2.2 Barlow than my 2.0. With the 8 Radian and 10 UWA either gives me a useful 133x or so in my TV85, which is often a sweet spot for lunar and planetary. I’m interested to hear the reports of big eyepieces and barlows, because in my little refractor even the Radian is a bit ungainly on the Barlow.

[PKDfan]

I have a one trick pony that i've not had functional for ages- Baader Mk. IV zoom + 2X 2" ED Olivon Barlow + 100ED for lunar duties. Extending the zoom and where its focal plane shoulder is and i guess optical design, a zoom, that raising it Boosts power dramatically compared to a single focal length and boosting that and getting only a small change in power.

Unfortunately i've not enough infocus to use it with my Evolux.

A 2X Barlow becomes 4X+ and by increasing the boost range the image quality can correspondingly improve also; by Slowing down the 100ED's F/9 feed into F/18 further into F/36+ the zoom becomes a precision HIGH power weapon.

I bought 5X PowerMate for a similiar effect for Ms. Clarity....just so she feels alittle superiour. Boosting the 5XPM can go to 7X+.

CSS
Lance
P.s. is this an ACTUAL --FREE LUNCH -- paradigm Tom ???

[eblanken]

Hi Richard (aka 25585) & All,

 

I have moved away from Barlows in two directions:

 

{A} I have invested in Complete Sets of Eyepieces:

      Pentax XW 68 Deg. 40mm, 30mm, 20mm, 14mm, 10mm, 7mm, 5mm, 3mm and

      TeleVue DeLite 62 Deg. 18.2mm, 15mm, 13mm, 11mm, 9mm, 7mm, 5mm, 4mm, 3mm and

      TeleVue Radians 57 Deg. {"The Even mm Honorary" DeLites} at 6mm, 8mm, 10mm, 12mm  and

      Vixen LV 45-50 Deg. 40mm, 25mm, 20mm, 18mm, 15mm, 12mm, 10mm, 9mm, 7mm, 6mm, 5mm, 4mm, 2.5mm

      so I get the smaller steps that using a Barlow would do and "cheating the Barlow Out" as Jon, Bobhen & Lance does "Boosting"  

      I like the 20mm of Eye Relief (ER) that all these tend to provide me and the "Standard" presentation throughout the sets.

 

{B} I have the APM Super-ZOOM 67 Deg. AFoV, 15.4mm to 7.7mm which essentially has a variable Barlow built into the ZOOM, so this gets me much packaged into a very functional eyepiece. I am pleased with the quality, but also have the option to go back to {A} at any time.

 

Best, 

 

Ed

Edited by eblanken, 22 April 2025 - 03:49 AM.

[GSwaim]

While technically not a Barlow I use a TeleVue 2.5x & 5x 1.25" PowerMate for visual observations on the planets/moon, & 4x 2" PowerMate for solar visual observations.

 

My eyepieces are Brandon: 2": 48mm, 1.25": 32mm, 24mm, 20mm, 16mm, & 12mm. 

 

I also have a TeleVue 2" 55mm Plossl that I use for  solar/moon observations on occasion.

Edited by GSwaim, 22 April 2025 - 08:10 AM.

[Jon Isaacs]

 

 

I have moved away from Barlows in two directions:

 

{A} I have invested in Complete Sets of Eyepieces:

 

I have complete sets or nearly so and only use Barlow's when I need magnifications not otherwise possible. I would be using a Barlow with all your sets to achieve magnifications betond what 3 mm and 2.5 mm can provide.

 

I find leaving the Barlow in place and using 2 or 3 well spaced shorter focal  length eyepieces works better than just Barlowing the shortest focal length because I can swap eyepieces without having to swap the Barlow. If I'm going from 600x to 800x, time is critical 

 

Looking at your sets, there are some gaps. The Vixen has a major gap between 4 mm and 2.5 mm. That's a 60% increase. In a scope with a 1200 mm focal length, that's 300x to 480x. 

 

I'm not sure why you say you can get finer steps than pulling the eyepiece back, that provides a zoom.

 

My friend Bruce (Astro-master) has made a science of using Barlows, extension tubes and the 17 mm and 13 mm Ethos to fine tune the magnification for his 18 inch Classic Obsession. He's drift timed the combinations so he knows the exact magnifications and takes advantage of the zoom effect offered by sliding the eyepiece back incrementally.

 

Jon

[therealdmt]

I often use my ES82° 11mm in a 2x ES Focal Extender (so as to yield an effective 5.5 mm focal length) in my 10" Dob for the planets and other small objects. Also use that combo sometimes in my 100mm refractor.

 

More typically in that 100mm f/9 refractor, I’ll use a Baader Hyperion Zoom with its matching 2.25x barlow.

 

Previous to that, I was using as my main eyepiece in the 100ED a Svbony 7-21 zoom in a Shorty barlow.

 

Later, that 7-21 zoom, often into a 3x (or sometimes a 2x) ES Focal Extender, became my main eyepiece in my 72ED refractor (though after about two or three years that combination got largely supplanted by the physically more compact and lighter Svbony 3-8 zoom, sans barlow) 

 

I think I’ve got 8 different barlows or focal extenders, but I’m not using them as much as I used to. A few of them have seen a lot of good use with my 8-24 and 7-21 zooms though

[John Huntley]

Mostly I don't use a barlow when observing by myself.

 

I have used my Parks GS 2x triplet barlow with the Svbony 7-21mm zoom when doing outreach and the combination performed quite well. The slightly extended eye relief that the barlow delivered was appreciated by some as well.

 

When observing on my own, at home, un-barlowed is my preference though.

[eblanken]

Hi Jon & All,

 

I have complete sets or nearly so and only use Barlow's when I need magnifications not otherwise possible. I would be using a Barlow with all your sets to achieve magnifications betond what 3 mm and 2.5 mm can provide.

 

I find leaving the Barlow in place and using 2 or 3 well spaced shorter focal  length eyepieces works better than just Barlowing the shortest focal length because I can swap eyepieces without having to swap the Barlow. If I'm going from 600x to 800x, time is critical 

 

Looking at your sets, there are some gaps. The Vixen has a major gap between 4 mm and 2.5 mm {I do have DeLite at 5mm, 4mm & 3mm and Pentax XW at 5mm & 3.5mm}. That's a 60% increase. In a scope with a 1200 mm focal length, that's 300x to 480x. 

 

I'm not sure why you say you can get finer steps than pulling the eyepiece back, that provides a zoom {Because I'm typically using a Meade M-8 at (203mm x 2,200mm, f/11) and my skies rarely support more than 200x, so APM ZOOM at 15.4 to 7.7mm gets me what I need on many occasions}.

 

My friend Bruce (Astro-master) has made a science of using Barlows, extension tubes and the 17 mm and 13 mm Ethos to fine tune the magnification for his 18 inch Classic Obsession. He's drift timed the combinations so he knows the exact magnifications and takes advantage of the zoom effect offered by sliding the eyepiece back incrementally.

 

Jon

 

Yes, I wish for TeleVue DeLites at 3.5mm and 2.5mm and 2.0mm, but that isn't likely . . . 

 

I also wish for DeLites at 6mm, 8mm & 10mm, but not likely either . . . 

 

Best,

 

Ed

 

P.S. I still have 2x & 3x Barlows . . . I just haven't used them as much in a while . . . 

Edited by eblanken, 22 April 2025 - 07:31 PM.

[manolis]

with my sw 12" i use barlows with a nikon hw 12.5 to get more mag ,  the 1.25 dedicated nikon barlow, a 1.6 nikon , a 2.7 APM ,a 2.5 powermate and a tak 2x (still testing that one ) and a combination of those. all of them are great and invisible to my eyes but my favorite so far is the 1.6 ( i haven't got good skies since i bought most of them but i don't observe as frequent as i like too also ).