Which of these Barlows should I buy?

[D Med]

Hello, I am new to this message board. This is actually my first post. I am also very new to astronomy. I recently bought my first telescope, but I have only used it once because of all the rain and cloudy nights. After using it, I quickly realized I need to upgrade my eyepieces. So just some info on my telescope, so that you can help me better. I have a 5 inch aperture, and 1000mm focal length. I do know the basics, I know I shouldn’t go over 300x magnification with my telescope specs, and I should get eyepieces that won’t overlap when I use a barlow. So with all that being said, these are the two eyepieces I am getting:

Baader Planetarium 10mm Hyperion Modular Eyepiece - 1.25"

Baader Planetarium 8mm Hyperion Modular Eyepiece for 1.25" and 2" Focusers

 

Now these are the three Barlow’s I am considering buying along with the eyepieces. Does anyone have any experience with either of these three? Any information would be appreciated! Which of the three would you recommend?

Baader Planetarium Hyperion Zoom Barlow 2.25X

ORION High-Power 1.25 Inch 2X 4-Element Barlow Lens

Televue 2x Barlow 1.25 inch (1-1/4 in.)

Thanks in advance!

[Louis D]

I wouldn't go above 200x, personally, with a 5 inch scope unless it's an APO refractor.  That being said, I'd spend the money on a 5mm BST Starguider from FLO instead of a barlow to get to that maximum power.

If you really want a barlow, hunt around for a used 1.25" Meade 140 2x barlow.  I have several samples of it, and each is as good as my 1.25" TV 2x barlow.  They usually go for about $35 to $45 used here in the US.  As a bonus, the optical element is 1.25" filter threaded (unlike the TV optical element), so it can be threaded directly onto any 1.25" eyepiece for a lower power boost.

[Waldemar]

Baader Planetarium Hyperion Zoom Barlow 2.25X

This one is a dedicated barlow for the Baader Hyperion 8-24mm zoom eyepiece...
The TV PowerMates are i.m.h.o. the best. They seem to disappear and just do what you want them to do. 

 

[Merlin66]

Not dedicated to the Hyperion.....

I use it for solar  imaging with various cameras - the T thread adaptor is  ideal.

 

[Waldemar]

41 minutes ago, Merlin66 said:

Not dedicated to the Hyperion.....

I use it for solar  imaging with various cameras - the T thread adaptor is  ideal.

 

My bad... sorry

[Ricochet]

Depending on where you live, the atmosphere is likely to be the limiting factor before you get to 300x. In addition, 5 inch apperture and 1000mm focal length is a common spec for Jones-Bird style scopes. If you've got one of those then they are reportedly best at low powers and the 8mm you've ordered is likely to be the maximum the scope can take. 

[rwilkey]

Hi there, if I were you I would go for the AgenaAstro StarGuider Dual ED eyepieces found here:

https://agenaastro.com/catalogsearch/result/?q=starguider

These ep's are superb and will suit your telescope much better.  Don't worry about barlowing, the object is not to get the highest magnification, but to get a quality image for what the telescope best performs at.  The optimum performance for your scope would be around 120 - 130x magnification, and this would mean an 8mm (125x) eyepiece, after this consider the 12mm (83x) and then the 18mm (55x).  This line-up would make a great start for you. 

 

[D Med]

Thank you all for your helpful advise! I think for now I’m going to stick with just getting an 8mm eyepiece. I’ll get something else when I decide to upgrade telescopes. I live in rural Alabama, so my guess is the atmosphere is not too bad here. Lots of places with no light pollution. Maybe I’ll give a 5mm a try later down the road! Thanks again!

[Alan64]

I'm intrigued.  You have either the Celestron Omni XLT 120, or the Meade R5 LX70 kit, yes?  No?

A barlow is primarily for realising the higher powers, but without having to resort to a 4mm eyepiece with its tiny eye-lens and tight eye-relief...

You don't really need a 2" barlow.  A 1.25" 2x is adequate...

http://www.scopestuff.com/ss_eba4.htm

You can combine that with whichever 8mm you get, and for a simulated 4mm...

1000mm ÷ 4mm = 250x

A 5" aperture is certainly capable of 250x, especially if it's a refractor as I've guessed.

A 3x barlow can be quite useful as well... http://www.scopestuff.com/ss_eba3.htm

...and for maxing out that aperture.

[D Med]

On 21/12/2018 at 05:04, rwilkey said:

Hi there, if I were you I would go for the AgenaAstro StarGuider Dual ED eyepieces found here:

https://agenaastro.com/catalogsearch/result/?q=starguider

These ep's are superb and will suit your telescope much better.  Don't worry about barlowing, the object is not to get the highest magnification, but to get a quality image for what the telescope best performs at.  The optimum performance for your scope would be around 120 - 130x magnification, and this would mean an 8mm (125x) eyepiece, after this consider the 12mm (83x) and then the 18mm (55x).  This line-up would make a great start for you. 

 

Rwilkey, 

I went ahead and ordered an 8mm and 5mm of these eyepieces you recommended. Thank you so much for your recommendation, can’t wait to try them!

[D Med]

On 22/12/2018 at 08:51, Alan64 said:

I'm intrigued.  You have either the Celestron Omni XLT 120, or the Meade R5 LX70 kit, yes?  No?

A barlow is primarily for realising the higher powers, but without having to resort to a 4mm eyepiece with its tiny eye-lens and tight eye-relief...

You don't really need a 2" barlow.  A 1.25" 2x is adequate...

http://www.scopestuff.com/ss_eba4.htm

You can combine that with whichever 8mm you get, and for a simulated 4mm...

1000mm ÷ 4mm = 250x

A 5" aperture is certainly capable of 250x, especially if it's a refractor as I've guessed.

A 3x barlow can be quite useful as well... http://www.scopestuff.com/ss_eba3.htm

...and for maxing out that aperture.

Alan64,

I have a Newtonian reflector. You know you can get a 4mm with a bigger field of view, right? You don’t have to look into a small hole, if you upgrade eyepieces.

[Charic]

If you use an eyepiece focal length that has a smaller number than the telescopes focal length,  then you may be asking too much from the scope and may be disheartened with the result.
Its possible to reach higher magnifications, but sticking with my example or keeping somewhere that matches the aperture, so  ( 127mm 5" ) = 127x power will give  an image that the scope is capable with,  regards to the higher powers.
Actually using lower powers ( longer focal length eyepiece ) will make the image sharper, yet annoyingly smaller, due to the physics and how telescopes work.

Of the two eyepieces ordered, you'll probably find the 8mm more useable, as an example of using a longer focal length, then the 12mm  next if you stick with the same brand. I have the same eyepieces, branded BST over here in uk.

[Alan64]

8 hours ago, D Med said:

I have a Newtonian reflector.  You know you can get a 4mm with a bigger field of view, right? 

Ah, then this one...

https://cdn.shopify.com/s/files/1/0749/4383/products/CELE018_899aeaa1-c1f4-41c9-9505-8bc60496844a.jpeg?v=1510620661

...or the Meade variant?

Either is not a Newtonian in the traditional sense.  The design is a modern, loose simulation of a Jones-Bird catadioptric, and more difficult to collimate.  It's also an economical alternative to a C5 or 5SE Schmidt-Cassegrain.  I plan on getting one myself someday, but I never recommend them for those first starting out.  The problem with the design is the barlowing/corrective(?) lens assembly fitted near the end of the focusser's drawtube...

http://www.whichtelescope.com/images/CatadioptricNewtonian2.gif

In order to collimate the telescope in the usual manner, that lens assembly would need to be removed beforehand and reinstalled afterwards.  It would also help to center-spot the spherical primary-mirror.

Regarding a wider-angle 4mm, yes, I'm well aware.  In any event, the collimation will need to be spot on to enable sharp images at the higher powers.

[Charic]

Alan64, I had one of those, Powerseeker 127EQ, but quickly changed to the present scope!

[John]

These are excellent ultra-wide angle 4mm eyepieces with reasonably large eye lenses and 12mm of eye relief as well. Won't suit most who wear glasses when observing but much more comfortable than a 4mm ortho or plossl for those who don't and very good optical quality. OK, the price is higher than most plossls but it's a quality ultra-wide eyepiece

https://www.harrisontelescopes.co.uk/acatalog/ovl4nirvana.html

The above are also well corrected for use in faster scopes (eg: F/7 or faster).

[Alan64]

11 minutes ago, Charic said:

Alan64, I had one of those, Powerseeker 127EQ, but quickly changed to the present scope!

I want one with which to putter and tinker, to "fix".  I'm dying to find out what things look like at about 200x through it.  

[John]

15 minutes ago, Alan64 said:

I want one with which to putter and tinker, to "fix".  I'm dying to find out what things look like at about 200x through it.  

Trouble is, with a spherical primary mirror, quite a large secondary obstruction and an aversion to collimation tools such as the laser collimator, the lower cost bird-jones designs are rarely able to do justice to higher magnifications.

 

 

[D Med]

Yes, that’s my telescope. I have the Celestron 127 EQ Powerseeker. It wasn’t too bad when I collimate it. Took me about 20 mins. Corrective lens was easy to take out. I just got this telescope to start out. I plan on buying a Dob 8” in the future. I just wanted to get a feel for astronomy with a cheap scope first.

[Alan64]

1 hour ago, John said:

Trouble is, with a spherical primary mirror, quite a large secondary obstruction and an aversion to collimation tools such as the laser collimator, the lower cost bird-jones designs are rarely able to do justice to higher magnifications.

That's precisely what I want to try to do.

[Alan64]

1 hour ago, D Med said:

Yes, that’s my telescope. I have the Celestron 127 EQ Powerseeker. It wasn’t too bad when I collimate it. Took me about 20 mins. Corrective lens was easy to take out. I just got this telescope to start out. I plan on buying a Dob 8” in the future. I just wanted to get a field for astronomy with a cheap scope first.

Certainly, get an "observatory class" Newtonian on a Dobson alt-azimuth, but don't give up on the one at hand, as there's so much to do to the innards of that one before calling it quits.

[D Med]

3 minutes ago, Alan64 said:

Certainly, get an "observatory class" Newtonian on a Dobson alt-azimuth, but don't give up on the one at hand, as there's so much to do to the innards of that one before calling it quits.

Definitely, I don’t plan on upgrading anytime soon. I want to get decent with the one I have now before upgrading.

[Stub Mandrel]

I've got a Revelation Astro x3 ED barlow and it is very good for modest cost. Apparently the x2 version is very good as well.

[Alan64]

1 minute ago, D Med said:

Definitely, I don’t plan on upgrading anytime soon. I want to get decent with the one I have now before upgrading.

I'll tell you what I will be doing to mine, when I get it.  First, I'll take the telescope completely apart.  I'll place a polyvinyl(plastic, not paper) notebook reinforcement precisely in the center of the primary-mirror...

That way, I can use a collimation-cap...

I will then be able to see the exact nature of the collimation, and at a glance...

...and correct it where necessary.  But I'll need to remove the barlowing-element beforehand, and whilst I have it out, I'll blacken the edges of the lenses with chalkboard-black paint...

The inside of the drawtube would also be blackened with same, even over that of the factory's.  The paint I use is blacker than Synta's, incidentally.  The edge of the secondary-mirror , its backside, and the spider even, would get it too...

Not to mention anything else inside the tube that might reflect stray-light sources; shiny, black plastics...chromed nuts and screws...

...and all to improve contrast, to be seen to be believed when observing.  I viewed the Trapezium of Orion recently with a recently blackened and flocked telescope.  Instead of the edges of the grey cloud-like nebula blending and oozing into a not-quite-black sky background, the edges of the nebula stood out in stark contrast against a jet-black background. 

Flocking is like very-low pile carpeting... 

http://www.fpi-protostar.com/hitack.htm

All telescopes that come out of China, the tube interiors are of a greyish black paint, and with a bit of rust as a "bonus".  Apparently the unpainted, steel tubes are not kept in a dry place before the paint is applied...

Even the tubes of the more costly Schmidt- and Maksutov-Cassegrains appear as that on the inside, I'd wager.

In the end, you want the inside of any telescope to be utterly dead to all sources of stray light.  Contrast: that's what it's all about; mostly anyway.  The same goes for refractor diagonals and any other accessories that have reflective, shiny surfaces within.

 

[Stub Mandrel]

Heatproof black paint for car exhausts and wood stoves is particularly good as it is very matt and is blacker in the infra red as well which is good for imagers.

It's what I've used but I would think twice before spraying it on my backside (UK joke ? )

[Charic]

4 hours ago, D Med said:

Corrective lens was easy to take out.

You're not supposed to remove the corrective lens.

This type of telescope can be collimated by eye alone, no tools if the user needs. Its a spherical  mirror setup, you just need to see the mirror clips,  its in the user guide, but you could send it back  to get it collimated, but they'll do just the same, and charge you for it?

In order for the system to work with the eyepieces the corrector lens needs to be in place, so why remove it!!!!! 

I went the whole hog, strip, cleanse, build, adjust, collimate, no better, even with better eyepieces.