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What upgrades to look out for[Eyepiecies]?

Eyepieces Beginner
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#1 Krumons

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Posted 22 July 2021 - 08:50 AM

Hello. I would like to hear some suggestions about upgrades to look out for.

I have a Bresser Pollux 150/750 EQ3 reflector with the default kit that came with it (K4mm, RK20mm and 3x barlow).

My best achievements with this setup has been Saturn with rings to the point that I could see the gap between the planet and rings. Managed to see one red band on Jupiter and Io casting a shadow - both with the 4mm eyepiece.

I've tested the barlow with both eyepieces, but I tend to lose detail when using the barlow. Could be due to trouble focusing with the sticky focuser or the barlow is the culprit. Most of the time I just use the 4mm when looking at specific objects.

What I've done:
Replaced existing grease with lithium grease in the focuser - had a "Synta glue" situation
Bought a Cheshire eyepiece and did collimation - primary was one "donut" away from center if that makes sense.

I haven't tested the collimation out, so I'm not sure how much that one "donut" affected my views.

I am now looking for some eyepiece upgrades, but not sure which way to go first - barlow or eyepiece upgrades.

I cannot identify the brand or type of the eyepieces that came with the kit (RK20mm, K4mm). Not sure what would be a sufficient "upgrade" from my existing kit.


The store I am aiming at mostly offer Omegon, VIXEN and Explore Scientific(Out of price range for now) eyepieces. (I've heard VIXENs are good)

After watching this and a few other videos [https://www.youtube....h?v=S5oIBZ1KD2g], this is my gameplan:

One of eyepieces:
Omegon 10mm Plossl
VIXEN NPL 10mm
Omegon 4mm Super Plossl

Or just get something like Omegon 3x Achromatic Barlow and using my kit eyepieces.

My next target is improving detail on Jupiter and Saturn.

What are Your opinions about the eyepieces in my gameplan. Maybe some other suggestions from Omegon or VIXEN? My price range is around 40-50€ for an eyepiece.
What was the entry upgrade that improved your views the most?



 


Edited by Krumons, 22 July 2021 - 09:42 AM.


#2 psterngold

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Posted 22 July 2021 - 10:28 AM

Hi Krumons,

 

Hello from across the pond.

 

Congratulations on the (presumably) new scope!

 

Collimation is critical. Glad that you got a Cheshire and spent time on it.

 

A full donut misalignment will seriously degrade the image. I suspect you will be pleased with the improvement. I suggest you keep tweaking the alignment, see how changes impact not just the defocused star pattern, but also the in-focus images.

 

I'm only familiar with the Vixens from your list above. In general, I have had good to great results with Vixen products. Hard to go wrong with them.

 

I'm a TeleVue fan when it comes to eyepieces. Their Plossls are considered among the best of breed. You might want to consider those as well.

 

Also IMO, I would go for better eyepieces before thinking about a better barlow.

 

Hoping your scope and whatever eyepieces you end up with, provide years of glorious views and soul-satisfying experiences!

 

Clear skies,

Paul S.


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#3 CowTipton

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Posted 22 July 2021 - 10:36 AM

Yours is a fast scope at f5.

The eyepieces that were included are Kellner designs which are usually just okay.

Theoretically a good plossl should be sharper for you.  The only real downside is that at short focal lengths (10mm and below for example) the eye relief is very small so you really have to get your eye close to the lens.

They should be very sharp at the center though.

 

My best suggestion would be to get an affordable zoom eyepiece like the Svbony 135.  It's 7mm-21mm adjustable.  It's also small and light compared to other zooms.

This will give you a nice range of magnification and you can always combine it with your barlow to find your favorite setting on any object.


Edited by CowTipton, 22 July 2021 - 10:38 AM.

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#4 macdonjh

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Posted 22 July 2021 - 10:37 AM

Krumons,

 

Welcome to Cloudy Nights.

 

Your 4mm eye piece is a Kellner, a classic, simple design.  It won't be the best for wide-field views, but it doesn't sound like you've used it for that yet.  Some math:

Magnification = (telescope focal length) / (eye piece focal length) = (750mm)/(4mm) = 188x

True field of view = (eye piece apparent field of view) / (magnification [approximately] = (45 degrees) / (188x) = 0.24o (or 15 arc-minutes)

Exit pupil = (telescope aperture) / (magnification) = (150mm) / (188x) = 0.8mm

 

True field is the measure of how big a window to the sky you're looking through.  for viewing the planets, small windows are fine, the planets aren't very big.  Exit pupil is a way to understand how bright the image you see will be.  Larger exit pupils mean brighter images.  7-8mm is a practical limit at the large end because the pupil of your eye probably doesn't get any larger in diameter than that (even if you're young and fully dark-adapted).  2-3mm is pretty bright and good for compact objects like galaxies and globular clusters.  0.5-1mm is generally fairly dim but good for high magnification viewing of bright objects like the moon, planets and tiny objects like planetary nebulae.  There is a wide range of exceptions to these much simplified ranges, of course.

 

The RK20 is a "reversed Kellner", so an optical variant of your 4mm.  The math is similar: magnification38x, TFOV: 1.2o, exit pupil: 4mm.

 

As for upgrades: eye pieces are very personal, and everyone has an opinion.  First, I'd look to increase the range of magnifications you have.  A 30-40mm eye piece will provide you with 23-19x which will be good for big nebulae and open clusters and for seeing multiple objects in the same field of view (like the Double Cluster). 

 

A 6-8mm eye piece will provide 125- 94x a range useful for small open clusters, globular clusters and galaxies. 

 

That 4mm eye piece provides close to 200x, which may be quite high magnification for your location.  If you have steady skies, you might be able to see more details with higher magnification, but if your skies are turbulent, more magnification may just be blurry.

 

A good place to start, in my opinion would be some good quality Plossl eye pieces.  They have 50o apparent field of view, not that wide by today's standards, but they are inexpensive and I think will have better correction than the Kellners you have.

 

The next major step up in AFOV will be the 68o eye pieces.  Tele Vue Panoptics, Explore Scientific 68 series, I think the Orion Expanse, too.  I'm sure there are other brands which aren't as expensive as the Tele Vue offerings.  After these you get into wide field eye pieces: 82o (e.g. Tele Vue Nagler) and 100o (e.g. Tele Vue Ethos).  Note: I keep using Tele Vue in my examples because I like Tele Vue, it is a well-known brand.  Tele Vue is by no means the only manufacturer out there who makes these eye pieces though.  You'll have fun shopping.

 

So, some examples.  If you decide to try some Plossls:

  • 32mm: 23x magnification, 2.2o TFOV (pretty wide), 6.5mm exit pupil
  • 6mm: 125x magnification, 0.4o TFOV, 1.2mm exit pupil
  • 4mm: 188x magnification, 0.27o TFOV, 0.8mm exit pupil
  • Maybe consider a 10mm as well?  75x magnification, 0.7o TFOV, 2mm exit pupil (you may find many deep sky objects/ "faint fuzzies" are easier to see at 75x than 125x)

I don't use Barlow lenses.  I don't have a good reason for that, I just don't. 

 

Good luck with your search.   Shopping and trying different eye pieces is fun.  


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#5 vtornado

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Posted 22 July 2021 - 10:56 AM

Hello and welcome to the forum!

 

I assume the K in the eyepiece means Kellner.  (I don't know what RK means probably some modified Kellner.)  These are OK but can be improved.    A Plossl eyepiece would be slightly sharper and have a wider field.

Plossls have very tight eye relief under 10mm.  Some folks consider them uncomfortable.

 

Astrotech paradigm eyepieces will give you a wider field and more eye relief.  (Maybe not sharper).

A 5mm would be good for your scope or an 8 barlowed.

 

A barlow will give you a perception of fuzziness because you are increasing the magnification by 3x.  A 3x barlow with 

a 4mm eypiece is  just too much magnification for your scope.  A 20 with a 3x (6.3mm) is getting close to the sweet spot

for planetary magnification.   I usually view plants at 1x to 1.3x the diameter of the mirror in millimeters.

 

Most of planetary fuzziness is do to atmospheric seeing.   First view the planets when they are highest over the horizon.   I think this  is occurring about 3AM.   Seeing changes day to day and hour to hour, you have to try often and be patient.

 

 

Next make sure your scope is collimated.  After your adjustment do a star test to make sure it is right.

 

Yes it is hard to focus an f/5 scope at high power.   I have your scope too.  Removing the grease is a good idea.

You can also adjust the tension of the focuser but it is still hard.  Other ideas are replacing one focus wheel with

a larger one (like a plastic jar lid).

 

Some barlows are indeed junk.  If the lens set is a singlet (you have to disassemble the lens to tell) or is plastic.

Then a barlow upgrade would be good.  Get a 2x.   Not 3.



#6 sevenofnine

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Posted 22 July 2021 - 11:11 AM

A simple and inexpensive improvement would be a good quality 32mm plossl and the Celestron 24-8mm zoom eyepieces. Those can work for you for a long time. The 32mm would be your "finder" eyepiece and the zoom for closer views. The zoom has the advantage of a decent sized ocular and good ER compared to the higher powered plossls. The FOV expands as you zoom to the highest power which is a big plus when manual tracking. Of course if there's more $$$ in the budget then you can move up the quality ladder to the Baader zoom but the Celestron is fine IMO. Good luck with your choices! waytogo.gif


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#7 Dave Mitsky

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Posted 22 July 2021 - 11:24 AM

The Astro-Tech Paradigm Dual ED eyepieces that Astronomics, the sponsor of Cloudy Nights, sells are very good for their relatively low price.  They have enhanced eye relief and 60-degree apparent fields of view, attributes which exceed those of Kellners and Plössls.  CN members get a small discount.

 

https://www.astronom...iece_series=478

 

https://www.cloudyni...y_discount.html

 

https://www.celestro...ossary-of-terms (definitions)


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#8 Sky Muse

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Posted 22 July 2021 - 02:28 PM

Your telescope has a 2" focusser.  It appears to be of plastic...

 

https://www.bresser....lar-Filter.html

 

My own 150/750 has a 1.25" focusser, of plastic as well...

 

6 f5pq.jpg

 

It is easy to miss, not to notice, but the focusser plays a very important part in the collimation process.  It consists of a smaller tube, the draw-tube, inserted into a slightly larger tube, the focusser's housing.  When the draw-tube is racked outward all the way, it should not wobble, move from side to side.  There are fixes for that, if such arises.  In the end, the draw-tube is to rack in and out straight and true, with no binding or slop.

 

Also, when using the Cheshire, you want to clamp it into the eyepiece-holder as you would an eyepiece, in the same position as the eyepiece will be whilst observing.  Do not use shims with a collimator of any type, in the unnecessary attempt to center it.  



#9 aeajr

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Posted 22 July 2021 - 03:12 PM

The Astro-Tech Paradigm Dual ED eyepieces that Astronomics, the sponsor of Cloudy Nights, sells are very good for their relatively low price.  They have enhanced eye relief and 60-degree apparent fields of view, attributes which exceed those of Kellners and Plössls.  CN members get a small discount.

 

https://www.astronom...iece_series=478

 

https://www.cloudyni...y_discount.html

 

https://www.celestro...ossary-of-terms (definitions)

Krumons

 

Welcome to Cloudy Nights

 

I would like to second Dave's recommendation. If you are trying to keep the cost down, these are an excellent value.

https://www.astronom...iece_series=478

 

Discussion about Paradigm eyepieces (Would also apply to the Agena Astro Starguider Dual ED)

https://www.cloudyni...s/#entry8229760
https://www.cloudyni...s/?hl=+paradigm

 

 

Understanding Telescope Eyepieces- There are recommendations, based on budget,
but the meat of the article is about understanding the considerations and specifications
to know when selecting eyepieces.
https://telescopicwa...cope-eyepieces/


Understanding and using a Barlow Lens
https://telescopicwa...ens-and-how-to/

 

 

THE ZOOM EYEPIECE INSTEAD OF OR IN ADDITION TO SINGLE FOCAL LENGTH EYEPIECES – The zoom is my favorite eyepiece.

 

TIGHT BUDGET? – Get a zoom and a Barlow     An 8-24 mm zoom eyepiece plus a Barlow somewhere between 2X and 3X will give you almost the full typical range of most scopes for as little as $100. Add one or two low power wide view eyepieces and you have that full range.

 

The zoom is single eyepiece that effectively replaces a range of eyepieces.  Works like the zoom lens on a camera. 

 

The zoom sounds great, but there is a trade-off.  The field of view of the zoom runs from a narrower AFOV at the 24 mm range to a wider FOV at the 8 mm range.  So, like any approach, the zoom is a compromise.  I find that compromise quite acceptable when weighed against the benefits listed below, I prefer the zoom.

 

I use the Baader Hyperion Zoom 8-24 mm in my 8” (now sold) and now my 12” Dob.  Usually this is the only 1.25” eyepiece that I use. 

 

Lower cost zoom – Celestron 8-24 – This was my first zoom.  Works well at the price and a good way to test your interest in zooms. 
Higher priced Zoom – Baader Hyperion 8-24 mm – My main eyepiece in my 12" Dob and 4" Refractor. 
https://agenaastro.c...lanetarium.html

 

  • I never expected the zoom eyepiece to become my primary eyepiece, but it has.
  • With a zoom, the eyepiece seems to disappear as you just move in and out at will, no swapping, no thinking about eyepiece changes
  • The Celestron 8-24 zoom is good and comparable to my Plossl eyepieces
  • The Baader Hyperion is great and comparable to my Explore Scientific eyepieces
  • Watching doubles split as I rotate the barrel is wonderful
  • One filter serves over a wide range of magnifications, no screwing and unscrewing to try other eyepieces
  • Moving smoothly between small changes in magnification helps when seeing is not the best
  • I am always working at the optimum magnification for this target.
  • Sharing the view with others is easier, especially in my manual tracking Dob - I hand it over at low mag so it stays in the view longer.  They zoom back in to whatever magnification works best for them.
  • My eyepiece case has been greatly simplified
  • Kids love the zoom

When I observe, 90% of the time, in all of my scopes, I use one or two low power, then the zoom. 



#10 therealdmt

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Posted 23 July 2021 - 01:02 AM

Hello. I would like to hear some suggestions about upgrades to look out for.
...
What was the entry upgrade that improved your views the most?

A Svbony 7-21 zoom (different than their 8-24 zoom which I have no experience with) plus a decent but quite affordable 1.25" SkyWatcher 2x barlow. Together they cost under $100

 

I've since upgraded the zoom and barlow to the Baader 8-24 zoom and a matching Baader 2.25x barlow, and they are both a bit better in some ways (though both somewhat worse in terms of convenience of use). Regardless, the SvBony 7-21 zoom and SkyWatcher 2x barlow were definitely the big beginning breakthroughs for me. YMMV


Edited by therealdmt, 23 July 2021 - 01:06 AM.

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#11 Krumons

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Posted 23 July 2021 - 03:54 AM

Hi Krumons,

 

Hello from across the pond.

 

Congratulations on the (presumably) new scope!

 

Collimation is critical. Glad that you got a Cheshire and spent time on it.

 

A full donut misalignment will seriously degrade the image. I suspect you will be pleased with the improvement. I suggest you keep tweaking the alignment, see how changes impact not just the defocused star pattern, but also the in-focus images.

 

I'm only familiar with the Vixens from your list above. In general, I have had good to great results with Vixen products. Hard to go wrong with them.

 

I'm a TeleVue fan when it comes to eyepieces. Their Plossls are considered among the best of breed. You might want to consider those as well.

 

Also IMO, I would go for better eyepieces before thinking about a better barlow.

 

Hoping your scope and whatever eyepieces you end up with, provide years of glorious views and soul-satisfying experiences!

 

Clear skies,

Paul S.

Thank you for the reply!

Indeed, after seeing a few posts/videos I quickly realised that collimation is very important and eventually I'll have to do it myself. I was a bit hesitant at first to not mess something up, but after getting familiarized with my scope, I realized it's not that mechanically complex.

I think I'll stick with VIXEN for now, and then ship some TeleVues in the next upgrade.



#12 Krumons

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Posted 23 July 2021 - 03:58 AM

Yours is a fast scope at f5.

The eyepieces that were included are Kellner designs which are usually just okay.

Theoretically a good plossl should be sharper for you.  The only real downside is that at short focal lengths (10mm and below for example) the eye relief is very small so you really have to get your eye close to the lens.

They should be very sharp at the center though.

 

My best suggestion would be to get an affordable zoom eyepiece like the Svbony 135.  It's 7mm-21mm adjustable.  It's also small and light compared to other zooms.

This will give you a nice range of magnification and you can always combine it with your barlow to find your favorite setting on any object.

Thank you for the reply!

I never considered zoom eyepieces, very useful piece of advice. Seems like one zoom piece in the set would be very useful for general observation, and then specific eyepieces for specific types of targets.


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#13 Krumons

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Posted 23 July 2021 - 04:32 AM

Krumons,

 

Welcome to Cloudy Nights.

 

Your 4mm eye piece is a Kellner, a classic, simple design.  It won't be the best for wide-field views, but it doesn't sound like you've used it for that yet.  Some math:

Magnification = (telescope focal length) / (eye piece focal length) = (750mm)/(4mm) = 188x

True field of view = (eye piece apparent field of view) / (magnification [approximately] = (45 degrees) / (188x) = 0.24o (or 15 arc-minutes)

Exit pupil = (telescope aperture) / (magnification) = (150mm) / (188x) = 0.8mm

 

True field is the measure of how big a window to the sky you're looking through.  for viewing the planets, small windows are fine, the planets aren't very big.  Exit pupil is a way to understand how bright the image you see will be.  Larger exit pupils mean brighter images.  7-8mm is a practical limit at the large end because the pupil of your eye probably doesn't get any larger in diameter than that (even if you're young and fully dark-adapted).  2-3mm is pretty bright and good for compact objects like galaxies and globular clusters.  0.5-1mm is generally fairly dim but good for high magnification viewing of bright objects like the moon, planets and tiny objects like planetary nebulae.  There is a wide range of exceptions to these much simplified ranges, of course.

 

The RK20 is a "reversed Kellner", so an optical variant of your 4mm.  The math is similar: magnification38x, TFOV: 1.2o, exit pupil: 4mm.

 

As for upgrades: eye pieces are very personal, and everyone has an opinion.  First, I'd look to increase the range of magnifications you have.  A 30-40mm eye piece will provide you with 23-19x which will be good for big nebulae and open clusters and for seeing multiple objects in the same field of view (like the Double Cluster). 

 

A 6-8mm eye piece will provide 125- 94x a range useful for small open clusters, globular clusters and galaxies. 

 

That 4mm eye piece provides close to 200x, which may be quite high magnification for your location.  If you have steady skies, you might be able to see more details with higher magnification, but if your skies are turbulent, more magnification may just be blurry.

 

A good place to start, in my opinion would be some good quality Plossl eye pieces.  They have 50o apparent field of view, not that wide by today's standards, but they are inexpensive and I think will have better correction than the Kellners you have.

 

The next major step up in AFOV will be the 68o eye pieces.  Tele Vue Panoptics, Explore Scientific 68 series, I think the Orion Expanse, too.  I'm sure there are other brands which aren't as expensive as the Tele Vue offerings.  After these you get into wide field eye pieces: 82o (e.g. Tele Vue Nagler) and 100o (e.g. Tele Vue Ethos).  Note: I keep using Tele Vue in my examples because I like Tele Vue, it is a well-known brand.  Tele Vue is by no means the only manufacturer out there who makes these eye pieces though.  You'll have fun shopping.

 

So, some examples.  If you decide to try some Plossls:

  • 32mm: 23x magnification, 2.2o TFOV (pretty wide), 6.5mm exit pupil
  • 6mm: 125x magnification, 0.4o TFOV, 1.2mm exit pupil
  • 4mm: 188x magnification, 0.27o TFOV, 0.8mm exit pupil
  • Maybe consider a 10mm as well?  75x magnification, 0.7o TFOV, 2mm exit pupil (you may find many deep sky objects/ "faint fuzzies" are easier to see at 75x than 125x)

I don't use Barlow lenses.  I don't have a good reason for that, I just don't. 

 

Good luck with your search.   Shopping and trying different eye pieces is fun.  

Thank You for the response!

The math was a dark spot for me, besides calculating magnification. Really helpful in understanding the other parameters.

Never thought of the longer focal lengths, but they will definitely be useful when the skies get a bit darker in autumn. Thank you for the DSO targets, I'll have something to start with when I get longer eyepieces and skies get a bit darker. I'm at Latitude 54, so nights are not that dark at the moment.

 



#14 Krumons

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Posted 23 July 2021 - 04:42 AM

Hello and welcome to the forum!

 

I assume the K in the eyepiece means Kellner.  (I don't know what RK means probably some modified Kellner.)  These are OK but can be improved.    A Plossl eyepiece would be slightly sharper and have a wider field.

Plossls have very tight eye relief under 10mm.  Some folks consider them uncomfortable.

 

Astrotech paradigm eyepieces will give you a wider field and more eye relief.  (Maybe not sharper).

A 5mm would be good for your scope or an 8 barlowed.

 

A barlow will give you a perception of fuzziness because you are increasing the magnification by 3x.  A 3x barlow with 

a 4mm eypiece is  just too much magnification for your scope.  A 20 with a 3x (6.3mm) is getting close to the sweet spot

for planetary magnification.   I usually view plants at 1x to 1.3x the diameter of the mirror in millimeters.

 

Most of planetary fuzziness is do to atmospheric seeing.   First view the planets when they are highest over the horizon.   I think this  is occurring about 3AM.   Seeing changes day to day and hour to hour, you have to try often and be patient.

 

 

Next make sure your scope is collimated.  After your adjustment do a star test to make sure it is right.

 

Yes it is hard to focus an f/5 scope at high power.   I have your scope too.  Removing the grease is a good idea.

You can also adjust the tension of the focuser but it is still hard.  Other ideas are replacing one focus wheel with

a larger one (like a plastic jar lid).

 

Some barlows are indeed junk.  If the lens set is a singlet (you have to disassemble the lens to tell) or is plastic.

Then a barlow upgrade would be good.  Get a 2x.   Not 3.

Thank you for the reply!

Replacing the grease made the focuser much easier to adjust. The old grease felt like dried out glue stick.
I also noticed that there's another thumbscrew on the 2'' part which adjust tension on the focuser tube and the cover that holds in pinion wheel is held in loosely by the screws and that also affects the tension. Ended up tightening it just enough that I don't get any play in the focuser, and now it's like day and night compared to the tension I had before.



#15 Krumons

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Posted 23 July 2021 - 05:58 AM

Your telescope has a 2" focusser.  It appears to be of plastic...

 

https://www.bresser....lar-Filter.html

 

My own 150/750 has a 1.25" focusser, of plastic as well...

 

attachicon.gif6 f5pq.jpg

 

It is easy to miss, not to notice, but the focusser plays a very important part in the collimation process.  It consists of a smaller tube, the draw-tube, inserted into a slightly larger tube, the focusser's housing.  When the draw-tube is racked outward all the way, it should not wobble, move from side to side.  There are fixes for that, if such arises.  In the end, the draw-tube is to rack in and out straight and true, with no binding or slop.

 

Also, when using the Cheshire, you want to clamp it into the eyepiece-holder as you would an eyepiece, in the same position as the eyepiece will be whilst observing.  Do not use shims with a collimator of any type, in the unnecessary attempt to center it.  

Thank you for the input on focuser. This will probably be one of the next upgrades I look forward to.

I will test the collimation out and do a star test to see how I did. When collimating, I did use the Cheshire exactly as an eyepiece, and my focuser was all the way in, though I did not notice any movement in the focuser when collimating. Thank you for all the points you mentioned about collimation - this will increase my accuracy when I do it next time.


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#16 Krumons

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Posted 23 July 2021 - 06:08 AM

Krumons

 

Welcome to Cloudy Nights

 

I would like to second Dave's recommendation. If you are trying to keep the cost down, these are an excellent value.

https://www.astronom...iece_series=478

 

Discussion about Paradigm eyepieces (Would also apply to the Agena Astro Starguider Dual ED)

https://www.cloudyni...s/#entry8229760
https://www.cloudyni...s/?hl=+paradigm

 

 

Understanding Telescope Eyepieces- There are recommendations, based on budget,
but the meat of the article is about understanding the considerations and specifications
to know when selecting eyepieces.
https://telescopicwa...cope-eyepieces/

Understanding and using a Barlow Lens
https://telescopicwa...ens-and-how-to/

 

 

THE ZOOM EYEPIECE INSTEAD OF OR IN ADDITION TO SINGLE FOCAL LENGTH EYEPIECES – The zoom is my favorite eyepiece.

 

TIGHT BUDGET? – Get a zoom and a Barlow     An 8-24 mm zoom eyepiece plus a Barlow somewhere between 2X and 3X will give you almost the full typical range of most scopes for as little as $100. Add one or two low power wide view eyepieces and you have that full range.

 

The zoom is single eyepiece that effectively replaces a range of eyepieces.  Works like the zoom lens on a camera. 

 

The zoom sounds great, but there is a trade-off.  The field of view of the zoom runs from a narrower AFOV at the 24 mm range to a wider FOV at the 8 mm range.  So, like any approach, the zoom is a compromise.  I find that compromise quite acceptable when weighed against the benefits listed below, I prefer the zoom.

 

I use the Baader Hyperion Zoom 8-24 mm in my 8” (now sold) and now my 12” Dob.  Usually this is the only 1.25” eyepiece that I use. 

 

Lower cost zoom – Celestron 8-24 – This was my first zoom.  Works well at the price and a good way to test your interest in zooms. 
Higher priced Zoom – Baader Hyperion 8-24 mm – My main eyepiece in my 12" Dob and 4" Refractor. 
https://agenaastro.c...lanetarium.html

 

  • I never expected the zoom eyepiece to become my primary eyepiece, but it has.
  • With a zoom, the eyepiece seems to disappear as you just move in and out at will, no swapping, no thinking about eyepiece changes
  • The Celestron 8-24 zoom is good and comparable to my Plossl eyepieces
  • The Baader Hyperion is great and comparable to my Explore Scientific eyepieces
  • Watching doubles split as I rotate the barrel is wonderful
  • One filter serves over a wide range of magnifications, no screwing and unscrewing to try other eyepieces
  • Moving smoothly between small changes in magnification helps when seeing is not the best
  • I am always working at the optimum magnification for this target.
  • Sharing the view with others is easier, especially in my manual tracking Dob - I hand it over at low mag so it stays in the view longer.  They zoom back in to whatever magnification works best for them.
  • My eyepiece case has been greatly simplified
  • Kids love the zoom

When I observe, 90% of the time, in all of my scopes, I use one or two low power, then the zoom. 

Thank you for the input on zoom eyepieces. I think now I'll get the zoom piece and 80a filter as my first eyepiece upgrade. Then I'll look into specific eyepieces for specific types of targets. For some reason I never considered them. We have a saying "If it works for everything it works for nothing" - maybe that was the reason I never looked into them.

 

I know I didn't include my location in my profile, but do you know if Astronomics have a warehouse in Europe? Shipping/import costs from US are too high to consider ordering something across the pond.


  • aeajr likes this

#17 Sky Muse

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Posted 23 July 2021 - 02:12 PM

I think now I'll get the zoom piece and 80a filter as my first eyepiece upgrade. Then I'll look into specific eyepieces for specific types of targets. For some reason I never considered them. We have a saying "If it works for everything it works for nothing" - maybe that was the reason I never looked into them.

 

I know I didn't include my location in my profile, but do you know if Astronomics have a warehouse in Europe? Shipping/import costs from US are too high to consider ordering something across the pond.

There is Amazon.co.uk...

 

https://www.amazon.co.uk/

 

There are also several vendors within the UK that ship out of the country.  Then, there is Teleskop Service, and Astroshop.eu, on the continent.

 

This zoom-ocular is well-regarded, as opposed to other 7-21 zooms...

 

https://www.teleskop...mm---1-25-.html

 

It is also sold under the Sky-Watcher and OVL marques.



#18 Sky Muse

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Posted 23 July 2021 - 02:15 PM

Thank you for the input on focuser. This will probably be one of the next upgrades I look forward to.

I will test the collimation out and do a star test to see how I did. When collimating, I did use the Cheshire exactly as an eyepiece, and my focuser was all the way in, though I did not notice any movement in the focuser when collimating. Thank you for all the points you mentioned about collimation - this will increase my accuracy when I do it next time.

It's not necessary to replace the focusser.  I've fixed several of my own plastic focussers, and they perform just fine...

 

https://www.cloudyni...c-focusser-fix/



#19 aeajr

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Posted 23 July 2021 - 02:40 PM

Thank you for the input on zoom eyepieces. I think now I'll get the zoom piece and 80a filter as my first eyepiece upgrade. Then I'll look into specific eyepieces for specific types of targets. For some reason I never considered them. We have a saying "If it works for everything it works for nothing" - maybe that was the reason I never looked into them.

 

I know I didn't include my location in my profile, but do you know if Astronomics have a warehouse in Europe? Shipping/import costs from US are too high to consider ordering something across the pond.

The best answer would be to contact Astronomics.

 

The Astro Tech Paradigm ED eyepieces are the same as the BST Starguider ED

I believe Barsta is actually the manufacturer.   They private label for Astro Tech and Agena Astro.  Common practice in the astronomy market.

https://www.firstlig...-eyepieces.html

 

Baader Hyperion Zoom

https://www.firstlig...m-eyepiece.html


Edited by aeajr, 23 July 2021 - 02:46 PM.


#20 Krumons

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Posted 23 July 2021 - 02:52 PM

There is Amazon.co.uk...

 

https://www.amazon.co.uk/

 

There are also several vendors within the UK that ship out of the country.  Then, there is Teleskop Service, and Astroshop.eu, on the continent.

 

This zoom-ocular is well-regarded, as opposed to other 7-21 zooms...

 

https://www.teleskop...mm---1-25-.html

 

It is also sold under the Sky-Watcher and OVL marques.

Thank You! 

 

Just wanted to know if I can support CN sponsor, when I'm going for next upgrades.

 

UK import and shipping fees are quite high as well. 




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