Telescope Eyepiece Quality

Kit eyepiece, far left, with three upgrades to the right.

I feel as though I'm always trying to persuade newcomers to astronomy about the importance of purchasing something better than the kit telescope eyepieces that come with most new telescopes.  My advice, however, usually seems to fall on deaf ears until, that is, the new telescope owner eventually gets to peer through a better eyepiece with their own eyes.  Then they are flabbergasted with mixed emotion, saying, "Wow...  I can't believe the difference!" as they smack their forehead with the palm of their hand instantly realizing all the time they wasted while dragging their feet about purchasing new, better eyepieces.

You see, these eyepieces that come packaged with new telescopes, generally speaking, are tiny, difficult to see through and less-than-sharp junk that border on useless.  I recently realized that if I write about this and show some photos, at least these people would be able to see the physical differences as I attempt to persuade them to upgrade their eyepieces and throw their kit eyepieces in the trash.  

When I was a child, I was fortunate enough to have parents who bought me a little Tasco 3½" or 4" reflector telescope.  Although I can't remember the exact size of this little reflector, I believe it had come from the Sears catalog like countless other things in our modest household.  This little flimsy telescope introduced me to the moon and provided countless nights of fun.  This beginner telescope was made of a white cardboard tube with a mirror in the bottom of it and with a very crude geared focuser at the top end.  No dust covers came with the telescope so dust was a constant problem.  I had no accessories for this telescope and the legs were flimsy, three-sided rolled metal of some sort but I was able to view the moon.  

The moon has always been a fascination of mine so this new little telescope provided a strong start in astronomy for me.  The biggest frustration however, even as a child, was the one or two eyepieces that came with this little telescope which happen to be no different than the eyepieces that come with new beginner telescopes today, many decades later.  Some things never change yet this is one that should have many decades ago.

The eyepieces that came with my first childhood telescope were tiny.  They were so small that even my child-sized eyes had difficulty looking through them!  I had to get so close to the tiny hole in the top of the eyepiece that I would see more magnified eyelashes than moon!  My eyelashes would be pushed up against the tiny top lens opening of the eyepiece making it appear as though a big spider with long wild legs was inside the eyepiece.  Once I started wearing eyeglasses, it simply was no longer possible to use this telescope because my eyeglasses prevented me from getting close enough to the tiny eyepieces to peer through the absurdly tiny hole.  As a child, I had no idea that there even was an option to upgrade anything on my telescope nor did I have any money anyway.

Unfortunately, things are no different today.  Every sub-$500 telescope comes packaged with virtually useless eyepieces.  There is usually a wide 20mm or 25mm eyepiece and another more magnified eyepiece in the 4-10mm range.  These eyepieces give blurry views, at best.  Worse yet, and perhaps the primary reason for this blog post, they are frustratingly difficult to look through because the hole in the top of the tiny eyepiece is like a little pin hole.  

Compounding this pin hole problem is the fact that you need to mash your eyeball as close to the eyepiece as you can get it so you can see the focus point.  The really bad news is, if you wear eyeglasses, you will not see anything at all through these ridiculously undersized eyepieces.  If you do not wear eyeglasses, you will likely be quickly frustrated by these tiny eyepieces because these eyepieces really are cheap junk and unbearably uncomfortable to use.  "Comfort" is a bigger issue than it sounds.  Lack of comfort causes unnecessary eye strain and limits stargazing time.  

I hear complaints about these kit eyepieces all the time from newcomers to astronomy and telescopes yet, because of their inexperience, they still think this is normal for all telescopes and not just cheap beginner telescopes.  As a result, they just press on and endure the discomfort and poor views.

The typical kit eyepiece shipped with new telescopes...
How can anyone be expected to see through that tiny lens opening?

Think about this...  You buy the biggest telescope you can afford knowing that a larger telescope will allow you to see more.  Now you have a nice new fairly decently-sized telescope but then you find that you must try to see through the supplied tiny eyepiece more closely resembling a pin hole!  Why?  This doesn't make any sense whatsoever!  There is absolutely no need for these frustratingly difficult to use eyepieces and they should never be packaged with a telescope.  Quite honestly, I don't even think they belong in today's market.  There are far too many good and outstanding eyepieces available.  Instead of providing two virtually useless eyepieces for free that are frustrating to use, the manufacturers should instead package a single decent eyepiece in the 15-20mm focal range depending upon the focal length of the telescope.  Later, the beginner can add a larger selection of eyepieces as needed.

Each month, I hear from numerous telescope beginners who are frustrated.  They are trying to figure out how to get decent views out of their brand new telescopes.  The first assumption they make, invariably, is that they are doing something wrong causing the terrible views.  The fact is the primary culprit causing poor views is the kit eyepieces.  Of course, I know there are other reasons for newcomer difficulties but the biggest problem is usually due to these ridiculously tiny kit eyepieces.  Rather than buy a few eyepieces that may actually cost as much as their cheap new telescope (purchasing a "cheap telescope" is another mistake made my inexperienced newcomers), they pack away the telescope because astronomy proved to be too difficult, frustrating and/or uncomfortable.  

I have four eyepieces from four separate eyepiece lines that I will use as examples.  One is typical of a kit eyepiece included with new telescopes (to the left in the group photo of eyepieces, below).  The other three eyepieces, as we move to the right in the photo, are upgrades...  one providing a moderate upgrade bordering on significant and two providing quite significant upgrades.  The physical differences when compared to the kit eyepiece are quite obvious in the photos on this page but many beginners do not understand this because they have never seen a comparison such as this one.  

Besides, who would think that their new telescope came packaged with useless eyepieces?  Unfortunately, new telescopes do come packaged with useless eyepieces.

So, for some reason, the new astronomers tend to think I am simply trying to get them to needlessly spend some additional money when I quickly mention upgrading their eyepieces.  Maybe they think I get some sort of commission on the sale of astronomy accessories.  In reality, I don't get any commissions.  I am simply trying to help the newcomers overcome the shortcomings of their new telescopes based on my own experiences.

So the first eyepiece to discuss here is an example suspect eyepiece that is typical of what is included with most new telescopes.  For this example, I have a Gosky 6mm Plossl.  The brand doesn't matter on this one because it is rebranded and used by almost all of the major telescope manufacturers as a kit eyepiece packaged with their new beginner telescopes...  in some cases, this example eyepiece is actually better than kit eyepieces that come packaged with new telescopes!  

You can clearly see a couple of major differences between the eyepieces in the photo, below, not the least of which is the top eyepiece lens openings.  Just looking at those top lens openings, which eyepiece do you think would be unbearably difficult and uncomfortable to use and see through for astronomers?

It is obvious in the photos that the hole you peer through on this typical kit eyepiece is so tiny that you can't even see the top lens.  Putting aside the fact that you need to try to see through this tiny peep hole, it would be impossible to wear eyeglasses when using any eyepieces like this one because you need to get so incredibly close to these little eyepieces that you mash your eyelashes against the eyepiece.  Since it is not possible to wear eyeglasses when using these eyepieces, they are very difficult and uncomfortable to use for some yet frustratingly impossible to use for many.  Yet this, unfortunately, is typical of a kit eyepiece that comes packaged with new beginner telescopes.  It is actually a bit disconcerting trying to get a peak through such a tiny opening in order to view through a comparatively large telescope...  it kind of gives me the heebie-jeebies.

The next eyepiece to discuss is a moderate step upward bordering on a significant upgrade.  This eyepiece was actually my first purchase of an upgraded eyepiece.  This eyepiece in the photo below is an Orion Expanse 6mm eyepiece.  The noticeable physical difference is the size of that top lens opening.  I breathed a sigh of relief when I first peered through one of these eyepieces after only struggling with the kit eyepieces that came with new telescopes.  I wish I had one of these when I was a kid studying the lunar surface!

In addition to the benefit of the obvious larger top eyepiece lens opening, the Orion Expanse line of eyepieces (four eyepieces in the lineup), provides a comfortable eye relief also.  Eye relief is the distance your eye needs to be above the top lens of the eyepiece (see diagram to right).  Since I wear eyeglasses and have adult-sized eyes as opposed to a small child, I find eye relief in the 15-20mm range to be most comfortable.  For children, you could shorten up that eye relief distance by a little bit but not a whole lot. 

This Orion Expanse line of eyepieces is comfortable to use with eyeglasses but just barely (eye relief for the 6mm Expanse eyepiece is 14.8mm).  Because this eyepiece "just barely" meets my comfortable eye relief requirements, I sometimes need to remove my eyeglasses in order to get ever so slightly closer so I can view the entire field of view to the edge of the viewing field.  Putting that aside, it is not absolutely necessary to remove my eyeglasses and it is easy and comfortable to view through these eyepieces even while wearing eyeglasses.  This is a very nice upgrade of only moderate cost while providing nice sharp views.  There is no doubt that this eyepiece is a vast improvement over the typical kit eyepiece.

The next step upward to show and describe here is the Baader Hyperion 8mm eyepiece.  This eyepiece looks drastically different than the previous two.  The first thing that jumps out is how large that top lens opening is compared to the typical kit eyepiece.  The top lens opening is BIG...  the whole eyepiece is BIG... it is beefier...  it is heavy...  it is chunky...  and peering through this eyepiece is a joy!  This Baader Hyperion line also offers crisper, more contrasty views.  The eye relief on these eyepieces is even more comfortable than the Orion Expanse line at a generous 20mm distance.  

I have Hyperion eyepieces in focal lengths of 8mm, 17mm, 24mm and 36mm.  The 24mm and 36mm give stunningly crisp wide-field views with stars looking like diamonds.  The Hyperion lineup includes nine eyepieces and a zoom eyepiece with a focal length of 8-24mm.  This is definitely a high quality line of telescope eyepieces with a complete lineup of focal lengths available.  

Even though Baader makes an even better line of eyepieces than the Hyperion line, with the Hyperion line we begin to feel as though the views through the eyepieces are "immersive".  Peering through these large eyepieces is shockingly comfortable and exciting.  Using one of these Hyperion eyepieces after using a kit eyepiece makes you feel as though you just bought a new telescope that is twice the size of your telescope's real size!  When an eyepiece can make you feel as though you just bought a new telescope, it is a very good eyepiece.

There are always better eyepieces out there though and, as good as this Hyperion line of eyepieces is, there is a better line of eyepieces also manufactured by Baader.  The best eyepieces I own are a few Baader Morpheus eyepieces.  In this group photo of eyepieces, below, I'm showing the 6.5mm Morpheus eyepiece, to the far right.  These eyepieces have even larger top lens openings than the Baader Hyperion eyepieces.  They provide all the benefits of the Hyperion line yet are a bit sharper and brighter as well.  The clarity is amazing.  Using these eyepieces is like sticking your whole head through a port-hole into space because it gives you a fully immersive and crystal clear view of space!  Compared to using a kit eyepiece, using a Morpheus eyepiece for the first time is definitely a jaw-dropping "WOW" moment.

Let's now talk about realistic pricing for upgrading a couple of eyepieces.  Telescope optics are comparable to photographic optics in that just like photographic camera lenses, the more you pay for a lens, generally speaking, the sharper and better the lens will be.  The same holds true for these slightly smaller telescope eyepieces.  The higher the price, the better the quality.  If the eyepiece came for free with your telescope, it probably does not represent "quality" and may very well be the weakest link in your optical chain needing upgrading as soon as possible.  There is a good possibility that simply upgrading one or two eyepieces could improve your views through your telescope significantly.

A good camera lens typically starts at around the $750 price point.  Around $500 will get you a decent camera lens though.  On the positive side, a decent telescope eyepiece is considerably less expensive and starts in the $50-60 range.  If you catch a sale, you can actually pick up the entire set of four Orion Expanse eyepieces for only $150.  A good quality telescope eyepiece starts around $150.  The noticeable lower cost of telescope eyepieces compared to camera lenses is due to smaller lenses used in each assembly and far fewer parts required by comparison.  Even so, some telescope eyepieces are still in the $750-1000 range.  These are also monstrous in size weighing multiple pounds and are meant for much larger telescopes than we are discussing here. 

Knowing that the beginner with a new telescope kit should upgrade their kit eyepieces to better eyepieces now presents a bit of a dilemma for the beginner since they know next to nothing about telescopes and telescope accessories.  How does someone choose a good eyepiece?  

First, although you may be tempted, don't bother with any eyepiece upgrade kits that come with a set of filters.  These eyepieces are hardly better than the kit eyepieces and the filters are low quality and will probably go unused anyway.  The one exception when it comes to filters would be purchasing a moon filter that screws into your eyepiece or diagonal.  A moon filter is a good idea because the moon is painfully bright when viewed through a telescope.  The moon filter will knock down some of that brightness similar to how sunglasses help you on a bright, sunny day.  Until you can spot the difference between good eyepieces and bad eyepieces, do not even consider the purchase an eyepiece kit.  

So, what should you look for in a new eyepiece?  

An upgraded eyepiece should be comfortable to use...  it should be easy to use...  it should provide clear, crisp views.  The first thing to consider is enough eye relief especially if you wear eyeglasses.  The specifications of each eyepiece for sale online will show the specified eye relief.  Aim for a minimum eye relief of 13-15mm.  If you wear eyeglasses, this is of utmost importance because, without this eye relief, you won't be able to view through the new eyepiece while wearing your eyeglasses.  Even if you don't wear eyeglasses, this eye relief is nice to have for comfort so you don't need to have your eye pressed up against the eyepiece.

As you have probably noticed by now, I have a pet peeve about the top lens opening too.  As is pretty obvious in the photos on this page, I always look for a large top lens opening.  The bigger, the better.  It is physically impossible for me to view through a small/tiny top lens opening.  Additionally, it is silly to have a fairly large telescope that is capable of expansive views and then to force yourself to try to look through a tiny peep hole.

If you can only purchase one eyepiece, start with one in the 20mm to 25mm range.  These focal lengths provide more moderate to wide views.  Later, you will want one with a more magnified view in the 8-10mm range. 

"Field of view" is another specification of a telescope eyepiece.  This is measured in degrees and, typically, a wider field of view is generally more desirable than a narrower field of view.  You really need to get a feel for various fields of view so you can make an informed decision based on your own uses and preferences.  For now, aim for a field of view in the middle range of around 68°, give or take.

Another factor is cost.  Eyepieces, for the most part, are more expensive as the quality improves.  My advice is don't bother with eyepieces that cost less than $50-60 each.  At less than this price point, any improvements you might get over the kit eyepiece is minimal, at best, and hardly noticeable most times.  You need to buy quality to make a noticeable difference.

If you are new to astronomy and telescopes or you are now shopping around for a first telescope, do yourself a huge favor...  Plan to upgrade your eyepieces immediately!  Add that cost into your budget and you will be far happier in the long run.  Steer clear of those "peep hole" eyepieces.  The better eyepieces will provide crisper views, wider views and be far more comfortable to use.  You will also experience far less frustration as you begin your journey in astronomy.  Also, these upgraded eyepieces will not be a waste of money because they can stay with you even if you eventually upgrade to a better telescope as you learn more and grow.

I'm actually very happy about my Baader eyepieces and they have made a world of difference for me.  I use the smaller Expanse eyepieces when I want to stay lightweight but I definitely prefer my relatively big Baader eyepieces!