barlow comparison

[david b]

hi i was wondering whats the best barlow between the celestron ultima and the tal x2. Can anyone give me a review on any of these models or do you know of any better barlows on the market. thanks for your time

[dweller25]

I have both.

The Tal is good value for money.

The Ultima is much more expensive but controls light scatter better so contrast is far superior. IMHO the Ultima is worth the extra money.

I also have a Televue barlow which gives identical performance to the Ultima.

HTH

[Saturnalia]

The only one I'm aware of that may improve on the Ultima or TeleVue is the Powermate (also made by TeleVue) which is available in 1.25" size at 2.5X and 5X or for 2" focussers, 2X and 4X.

[brianb]

IMHO the Ultima is worth the extra money.

Totally agree; the Ultima SV is the cheapest barlow that's worth buying. If you want Televue go for the Powermate.

[arad85]

Off topic, but related question. I have a Celestron Ultima. I also image with the DMK. I was thinking of getting a powermate for the 13mm Ethos and to be able to stack powermate/barlow when imaging. Do people think I'd notice much of a difference between 13mm Ethos/Celestron Ultima and 13mm Ethos/2x Powermate?

[John]

I've not much to add to the views posted so far other than to say I've owned the TAL 2x, an Ultima 2x, a Tele Vue 2x (Barlow) and a TV 2.5x Powermate and what's been said matches my experiences with those pieces very well indeed.

On the question arad85 raises re: Ultima 2x V's Powermate 2x with an Ethos 13mm, I reckon the Powermate would possibly optically be very slightly ahead of the Ultima with the added feature that it does not increase the eye relief as the Ultima will. For me a bigger issue would be mechanical in that I would not fancy the bulky Ethos hanging off the 1.25" Ultima wheras the 2x Powermate is a 2" accessory.

Many people use the Antares 1.6x barlow (also a 2" fitting) very sucessfully with the Ethoi's.

[Heavens Above]

Hi

The Astro Physics Barcon Barlow is not cheap but is trully superb, it is also modular allowing a range of magnification factors. For me it was a big step up on the Televue.

Tim

[johninderby]

When considering the Televue Barlow v Powermate the following quote from Televue is worth reading.

" You didn't say what type of scope you have. If you called Tele Vue, We would have recommended the Big Barlow if you have a Newtonian, and the powermate if you have a refractor. The reason?,

For the Nagler eyepieces the optical benefits of the powermate are invisible, however, ergonomically in a Newtonian both the BB and powermate will reach their parfocal point.

In a refractor, where a diagonal is used, the BB will not come close to reaching it's parfocal point, and an inch or so of in-travel will be required. "

John

[TheThing]

It's a no brainer!

The Tal is a much better Barlow for less money. And it's bullet proof!

[arad85]

For me a bigger issue would be mechanical in that I would not fancy the bulky Ethos hanging off the 1.25" Ultima wheras the 2x Powermate is a 2" accessory.

I've done it a couple of times and as the eyepiece is in a dob, as long as you do up the screws (and the one on the 13mm to grip the Ultima) it's fine.

Many people use the Antares 1.6x barlow (also a 2" fitting) very sucessfully with the Ethoi's.

Nice idea. 1.6x the 31 would give me 20mm - perfect intermediate eyepiece between the 13mm and 31mm. It would also give me an 8mm when used with the 13mm... And I could use it in front of the 2x barlow when imaging (my setup gives me more like 3x barlow where I place it in the imaging train, so that's a x5 for planets)... <strokes chin> hmmmm - thanks John!