90 replies to this topic

[Mr. Pepap]

Hi all,

 

I've had a Celestron 8SE for a few weeks now and have been happily scanning away at the night skies looking at lots of interesting things. I recently joined this website so I can improve my knowledge of astronomy and improve my overall experience. I am ready to start buying some equipment for it and would appreciate you all's help.

 

My question involves the difference between zoom eyepieces and "regular" ones. I want to be able to look at things with a higher magnification, but I don't have much money to spend. What is the difference between these two types of eyepiece? Is it better to buy a zoom eyepiece and save a few bucks, or buy multiple eyepieces of varying focal lengths? I am ok with buying one or two more eyepieces, but I don't want to go too crazy.

 

I would appreciate any help and look forward to hearing back from you all!

[f74265a]

What eyepieces do you have already?
And approx what is your budget? The definition of not much varies from person to person.

[Mr. Pepap]

What eyepieces do you have already?
And approx what is your budget? The definition of not much varies from person to person.

I currently only have the 25mm eyepiece that came out of the box. My budget is ~$200

[cookjaiii]

Welcome to Cloudy Nights!

 

Some people will say that zooms are not as sharp as fixed focal length eyepieces.  That hasn't been my experience.  Zooms do have one major weakness and that is a narrow field of view at lower magnifications.  The field widens as you increase the magnification, and the range is approximately 40-60 degrees from one extreme to the other. You can complement your zoom with one low-magnification fixed eyepiece to give you wider fields (for example a 25mm or a 32mm Plossl).  Those two eyepieces will cover all your viewing needs.  Spend some time with those two and you will eventually figure out how you like to use your telescope.  With that knowledge you will make better decisions about you next purchase.

 

You picked a nice telescope and when Jupiter comes around again later this year, it will knock your socks off.  

Edited by cookjaiii, 24 February 2021 - 08:37 PM.

[TOMDEY]

Think of it the same as interchangeable camera lenses. The Zooms are convenient and versatile; the fixed focal length ones generally perform far better. If you're photographing an "event" like a road trip or party, the zoom is most practical. If you're concentrating on one particular subject and want to capture it as perfectly as possible, you select the best fixed focal length from the stable. The Zoom may cost more than a typical single Fixed, but that stable of specialty lenses will cost way more than the Zoom. In that sense, a Zoom is a great ~cheap~ and convenient option, especially for the beginner who hasn't built up an assortment of good eyepieces over the years.    Tom

[sevenofnine]

I have both the Celestron and Baader Mark IV zooms. They are both good eyepieces in my scopes. The main difference is that the Baader has a wider FOV throughout the range. If that matters to you then save up or buy used. They do come up for sale occasionally in the classifieds on this forum. The Celestron is the better "deal" in my opinion. The FOV is narrower but the center sharpness is very good. Even if you change your mind on zooms it's a good learning experience. You will discover what focal length eyepieces you like the most. Good luck with your decisions! 

[aeajr]

Hi all,

 

I've had a Celestron 8SE for a few weeks now and have been happily scanning away at the night skies looking at lots of interesting things. I recently joined this website so I can improve my knowledge of astronomy and improve my overall experience. I am ready to start buying some equipment for it and would appreciate you all's help.

 

My question involves the difference between zoom eyepieces and "regular" ones. I want to be able to look at things with a higher magnification, but I don't have much money to spend. What is the difference between these two types of eyepiece? Is it better to buy a zoom eyepiece and save a few bucks, or buy multiple eyepieces of varying focal lengths? I am ok with buying one or two more eyepieces, but I don't want to go too crazy.

 

I would appreciate any help and look forward to hearing back from you all!

You can see my eyepiece set in my signature.  I have a good spread of single FL and zoom eyepieces.

 

So, when I am observing, my eyepieces of choice are one or two low power, then go to the zoom.

 

TIGHT BUDGET? – Get a zoom and a Barlow     An 8-24 mm zoom in an 8SE will give you almost the full typical range of the scope.  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.

 

In a GoTo scope, where the mount tracks, the narrower field of view at the low power end becomes less of a concern. In a manual scope where drift time matters, some people don't care for zooms.   I have both types of mounts and both types of eyepieces.  I prefer the zoom in both. 

 

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.  In my AD12 12” Dob I use the Baader Hyperion 8-24 zoom for the midrange, up to 190X, then I typically go to single FL 82 degree eyepieces.  As I have a low power wide view 20 mm eyepiece I tend to use the zoom mostly in the 18 mm to 8 mm range.   Then I go to 6.7, 5.5 and 4.7 mm 82 degree eyepieces for more drift time .

 

Baader Hyperion 8-24 mm – My main eyepiece in the XT8i – $290  There are other choices.
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

 

Hope that was helpful. 

Edited by aeajr, 24 February 2021 - 10:02 PM.

[scarubia]

Great post aeajr!

 

I'd like to add that maintaining balance in non-goto dobs with one EP is refreshing . I use a Leica Zoom in my 10" and  never realized how much of a pain switching EP's was until I didn't have to do it!

[CarolinaBanker]

I’d recommend a zoom, but with your budget you could also get 4 Takahashi Starbase Orthos and a Barlow. I recently bought a zoom and it is incredibly convenient, no need to change out eyepieces, eye relief is comfortable from 7-21mm and with a Barlow I can go to magnification that is fine for planetary purposes.

[SeattleScott]

A zoom isn’t a bad way to go on a SCT. The F10 focal ratio helps minimize their optical inferiority to quality fixed eyepieces. The Baader is about 10% wider than the Celestron, and probably a little sharper, better corrected. But it costs a lot more, over your budget, although $200 could possibly work buying used.

If I were to come up with an alternative set of fixed eyepieces for $200, it would be something like 15mm Paradigm, 9mm Xcel LX and 6.5/7mm Xcel LX. This might run up to $230 or so with pandemic price increases. You could wait a bit on the high power eyepiece, say next summer when the planets are back. Which probably means placing an order now...

If you get a zoom, you should still consider a low power eyepiece like a 32mm Plossl for maximum field of view. And maybe a 6-7mm for maximum magnification, like the Xcel LX, or a barlow to barlow the zoom.

Tom said it pretty well. There are different levels of quality, both with fixed eyepieces and zooms, so you can’t say that fixed is always better. For example, that Leica Zoom mentioned costs close to $1,000. Better than many premium fixed eyepieces. But a $65 Celestron Zoom is generally going to be inferior to a $65 fixed eyepiece. And a $280 Baader zoom will generally be inferior to a $280 fixed eyepiece. But a zoom covers a range of focal lengths, so maybe a fairer comparison is the $65 Celestron zoom versus three $20-25 fixed eyepieces. Or the Baader zoom versus three $90 Xcel LX. That levels the playing field a bit. So if budget is a major driver, a Zoom isn’t a bad approach.

Orion seems to be coming out with a new zoom with 42-65 AFOV, virtually the same as the BHZ, for around $130 if I remember correctly. 7.2mm to 21.6. So you probably wouldn’t even need to get a high power 6-7mm eyepiece. Maybe add a 32mm Plossl and call it good. Of course we have no idea how well it performs yet.

Scott

[Jon Isaacs]

My two cents:

 

I'm not one who uses zooms much. I have the Baader Zoom, have had the Celestron Zoom. For my scopes and my style, fixed focal lengths work better.  My scopes are fast, manually tracked and I have a collection of top notch 68 degree, 82 degree and 100 degree eyepieces. 

 

But zooms have advantages, the ability to dial in the magnification in real time can be very useful, no guess work swapping eyepieces. And For many observers, just needing a few eyepieces is nice.

 

Regarding the Celestron zoom:  I think of it as a good eyepiece. In a fast scope, it's very good at the shorter focal lengths, not so sharp off-axis at the long focal lengths. In an F/10 SCT, it should be fine. It's weakness is the narrow field of view at the longer focal lengths. Add that 32mm Plossl and you would be fine.

 

In my mind, it would be a good investment just to experience a zoom. 

 

Jon

[bobhen]

With your $200 budget and your C8 I would consider the Orion 7-21 zoom. The zoom will give you 285 to 95x. They are very good (there was a long thread here on CN about the Orion 7-21 zoom that you might want to review) and they are only $63.

 

The Orion 7-21 zoom will be all you need with the C8 for the moon and planets and small deep sky objects. Use the rest of your budget for a lowish power wide field eyepiece or two for deep sky observing and you will be all set for a while.

 

Bob

[Ernest_SPB]

Regular zoom EP provides more convenience in observing paying by reduced apparent field of view, moderate eye relief and image quality.

But there are a number of different eyepieces with zoom. E.g., 3-6 mm Nagler zoom is respectable one

It is better to discuss/consider specific model...

[aeajr]

I currently only have the 25mm eyepiece that came out of the box. My budget is ~$200

 

Now that we have debated single FL vs. zoom, each having its advantages, it comes down to short term and long term goals.

 

You have a scope that should be quite useable to 200X almost any night, perhaps 300X on the Moon.   And there will be nights of great seeing where you will be able to go higher.  So, how do you cover the full range of your scope as quickly as possible, staying as close to your budget as possible.  That is how I see it.

 

 

Trying to stay within your budget and giving you a good initial spread - you need 1 eyepiece and a Barlow.  That could be a Paradigm, a Celestron LX, ES 68 or ES82.  Your choice, but pick the one that is your low cost starter or pick the series that you plan to build over time.   Personally I lean toward the ES.  I am standardized on the ES and Meade 82s.  

 

 

Low power wide view - Assuming you stay with the standard 1.25" diagonal for now, that would be a 32 mm Plossl.  You can get pretty good ones for 30 to $50.   Celestron, Orion, Meade, GSO are all about the same and are all good.

 

2032 / 32 = 63X and about .78 degree FOV   That is about as wide as you can go in a 1.25" in that scope.

 

Your 25 mm will give you 81X - over time this will likely be phased out.

 

18 mm  = 113X

 

32 in 2X = 126X 

 

25 in 2X 162X

 

18 in 2X 224X 

 

Based on Paradigm and GSO Barlow, 35+ 60+ 35 = $130   And you have a workable spread.   You won't have super wide views but you will have enough to get started on a minimum budget.   Sub in higher priced if you wish.  I am just laying out a strategy. 

 

Use a 2.5X Barlow (GSO about $55) instead of a 2X Barlow and spread the mags a little differently.  Lots of ways to play the Barlow game. 

 

OR

 

Same 32 mm Plossl

 

Zoom 8-24   84X to 254X and everything in between.   This is the configuration you would use 90% of the time.  No Barlow required.     

 

Add a GSO 1.5X/2X Barlow for $35 and you shift the zoom range upward 1.5X or 2X, but you don't need it to start. 

 

Celestron Zoom, about $80   Baader Zoom, $290 (My recommendation)   There is also the SVBony 7-21.  I just got this one but have not had a chance to put it through its paces. 

 

 

 

You can stir the soup any way you like, but these are some options to help you get started.  Personally, for a new person, I like the Plossl +zoom option, especially with a GoTo scope that tracks.  Super wide is nice but more important to a manually tracked scope than a GoTo scope.

 

Over time you will likely add some higher priced wide view single FL eyepieces but the zoom will always be there to fill in the gaps or those quick sessions when you don't want to pull out the whole eyepiece set.  Grab the 32 Plossl and the zoom and you are set for the night. 

Edited by aeajr, 25 February 2021 - 09:58 AM.

[Jeff Morgan]

Tom said it pretty well. There are different levels of quality, both with fixed eyepieces and zooms, so you can’t say that fixed is always better. For example, that Leica Zoom mentioned costs close to $1,000. Better than many premium fixed eyepieces. But a $65 Celestron Zoom is generally going to be inferior to a $65 fixed eyepiece. And a $280 Baader zoom will generally be inferior to a $280 fixed eyepiece. But a zoom covers a range of focal lengths, so maybe a fairer comparison is the $65 Celestron zoom versus three $20-25 fixed eyepieces. Or the Baader zoom versus three $90 Xcel LX. That levels the playing field a bit. So if budget is a major driver, a Zoom isn’t a bad approach.

 

Safe to say that one generally gets what one pays for.

 

Also safe to say that if you are in the hobby long enough, you will "graduate" from the lower cost eyepieces to the higher cost eyepieces (whether fixed or zoom).

 

The Baader and higher (more expensive) units get good reviews. 

 

After owning the Nagler zoom I went for the Leica and have found it to be excellent. After three months of critically comparing it to my Delos and XW's, I found no downsides whatsoever. Sold the Delos and XW's seven years ago and have not missed them a day since.

[teashea]

I have several zoom eyepieces along with my regular eyepieces.  While I mostly use regular eyepieces, I find that the zooms work quite well.  

[scotsman328i]

I’ve been teetering on getting a Baader Mk IV zoom for a while now, y’all might push me over the edge with this thread. 

[Spile]

I chose a zoom because it gave me access to a range of focal lengths with the convenience of not having to swap eyepieces. The Barlow gives me up to 334x. The only other eyepiece I have is a wide angle 42mm.

 I have written up my experiences at https://astro.catshi...-zoom-eyepiece/

[aeajr]

Hi all,

 

I've had a Celestron 8SE for a few weeks now and have been happily scanning away at the night skies looking at lots of interesting things. I recently joined this website so I can improve my knowledge of astronomy and improve my overall experience. I am ready to start buying some equipment for it and would appreciate you all's help.

 

My question involves the difference between zoom eyepieces and "regular" ones. I want to be able to look at things with a higher magnification, but I don't have much money to spend. What is the difference between these two types of eyepiece? Is it better to buy a zoom eyepiece and save a few bucks, or buy multiple eyepieces of varying focal lengths? I am ok with buying one or two more eyepieces, but I don't want to go too crazy.

 

I would appreciate any help and look forward to hearing back from you all!

For me, the question here is not fixed vs. zoom.  I think you will want to have both.  The real question is, which do you get first?

 

Based on all I have read, in the past, zoom eyepieces were extremely narrow and the more moderately priced ones were of poor quality.   That is no longer true.  Today's zooms, even the moderately priced ones, work well and have, what many people would feel is a useable field of view.     

 

Remember that, at one time, a Plossl eyepiece was considered a significant upgrade from the Ramsden, Huygens, and Kellners which were the standard of the day.  A 50 mm AFOV was considered fairly wide. Now the Plossl is considered the entry level good quality eyepiece as other options have emerged. 

 

Even I, a strong zoom advocate, have a full range of fixed focal length eyepieces and I would not want to give them up.  They can do things the zoom can not do.   While I prefer the zoom, my fixed FL eyepieces get used. 

 

The zoom can do things the fixed focal length eyepieces can not do.  So why would I want to limit myself to one or the other?

 

Whether you start fixed and add a zoom later, or start with a zoom and add fixed later, I suggest you plan for both.  Start with whatever seems to fit your goals today. 

Edited by aeajr, 27 February 2021 - 06:36 AM.

[george tatsis]

I’ve been teetering on getting a Baader Mk IV zoom for a while now, y’all might push me over the edge with this thread. 

It's a dirty job, but someone has to do it!

 

George

[Jeff Morgan]

For me, the question here is not fixed vs. zoom.  I think you will want to have both.  The real question is, which do you get first?

 

...

 

Even I, a strong zoom advocate, have a full range of fixed focal length eyepieces and I would not want to give them up.  They can do things the zoom can not do.   While I prefer the zoom, my fixed FL eyepieces get used. 

 

...

 

The zoom can do things the fixed focal length eyepieces can not do.  So why would I want to limit myself to one or the other?

 

 

The very same mentality (or lack thereof) comes up with NV (night vision) comes up. It is a false premise that these equipment choices are "either or".

 

Back on point with Zoom lenses, today one can get an excellent quality zoom which can find a place in a well-rounded eyepiece case.

 

Sure one may not like a zoom lens (and we all have our likes and dislikes). But the Old Wives Tale they must be optically inferior should be put to rest, along with the Old Wives Tale that barlows degrade images. It's not 1960 anymore.

[SeattleScott]

For me it’s not an old wives tale. It’s actual experience. Granted I haven’t tried the Leica. I assume that is better than BHZ or Lunt that I have experience with.

I will say my Televue 3x barlow is excellent so I tend to agree with you there. Technically it adds glass to the path so it must be introducing SOME light scatter, but not a particularly noticeable amount. The zoom eyepieces do detectably lag fixed eyepieces at similar price point in my experience. Not by a lot, but noticeably.

Scott

[Jeff Morgan]

For me it’s not an old wives tale. It’s actual experience. Granted I haven’t tried the Leica. 

 

And to be fair, I have not tried the lower end zooms - some very well could have issues.

 

The only ones I have tried are the Tele Vue Nagler zoom, Zeiss, and both Leicas.

[aeajr]

As I have posted before, I find the Baader zoom comparable to my ES82s, just not as wide.

I have swapped back and forth over and over and don't see a significant image difference.

[Dave Mitsky]

One of my telescopes is a 6" NexStar Evolution SCT.  I occasionally use an 8-24mm Tele Vue Click Stop Zoom with this scope to good effect, although I prefer the premium fixed focal length 1.25" eyepieces in my collection.  Good zoom eyepieces do offer convenience and cost savings.