Eyepiece Shootout

Three top shelf eyepieces compared side by side.

I’ve come a long way from that red tubed K-Mart telescope my wife bought me one Christmas years ago when we were dating (um… 35ish years now – gulp). Slowly, my gear has progressed, my tastes matured, and experience started costing me more and more money. I’d never spent more than $100 on an eyepiece before, and then I won my first Televue Nagler eyepiece at the Winter Star Party in 2003, and it turned my little case of Plossels into trash when I looked through it on my LX-200. Each year I’d scrape together some cash and I’d buy a new one to add to my collection that February. Today I have a complete set, and I am quite proud of them. They are killer on my fine refactors. Somewhere along my journey, I turned into an imager, but I still like to do visual astronomy, and I’m even active in the local club and do some outreach programs myself.

I always thought Naglers were the best of the best, but a few friends have told me that I should try a few other premium models. The Televue Ethos line for example, and also Pentax was known for making exceptional glass. I had no idea Pentax even made telescope eyepieces. A vendor friend who now works at Pentax loaned me a 20mm XW series eyepiece. He offered to let me give it a try and see how it compared to my beloved Naglers. I also recently came into the possession of a Takahashi telescope that came with a 24mm eyepiece. I found myself with Nagler, Takahashi, and Pentax eyepieces all at the same time. This sounded like a golden opportunity for a shoot out!

Typical configuration for lunar observing at my favorite outreach location.

Whenever I run into someone who says they can’t tell the difference between premium optics and the more budget gear, I know they haven’t actually tried them both. Not really, or not under good testing conditions. You can tell, and it’s not that hard. When you get to the upper end though, the difference between the premium brands (and this goes for just about everything) get’s finer and more difficult to discern from a casual inspection. Any of these three eyepieces are going to blow you away when compared to the eyepieces that came with your mass produced brand telescopes. I’m not saying these are bad scopes either, but the best telescopes in the world are hampered by the quality of the eyepieces. Of course, you can easily spend more on your eyepiece collection than the scope itself, and so it’s no wonder that the eyepieces are not the central value when you buy yourself a telescope (most of the time).

Back to the task at hand, side by side, these top choices are pretty neck and neck and I can tell you it takes a very discerning eye to tell the difference. I’ll tell you in advance now, if you have any of these models, don’t get rid of them, and you will be happy with any of these three. I’ll also confess that while I do have considerable expertise when it comes to astrophotography, I am a pretty average Joe when it comes to visual. I know enough to be dangerous, and by no means do I consider myself an expert here. Never-the-less, I can tell you what I saw and it might help you with future purchase  decisions, or just make you feel better about what you have. Again, if you have any of these three brands, you can justifiably feel great.

Okay, so the night of the shoot out was during one of my Coffee & Cosmos events. We were looking at the first quarter Moon with a Sky-Watcher Mak-Cass. The Moon is my favorite visual target, and it is merciless when it comes to optical quality. I spent the evening swapping between the Pentax XW 20, the Takahashi LE 24mm, and a Nagler 20mm type 2 (I also compared with a Nagler 13mm type 5, but it was a much closer view, and I wasn’t sure how fair it would be).

For the first 10 minutes I could not see any difference in quality between the three oculars. The lunar details were crisp and well rendered. There was no ghosting or glare either, and I felt as if I were in orbit above the moon. In isolation, any of these three were the best eyepieces I’ve ever looked through.

I wasn’t sure what to look for really. The lunar terminator was glorious with all three eyepieces. The Pentax was noticeably the wider of the three (thus the WX moniker) and I had to tilt my head to see everything. It was like a peep hole out the bottom of an orbiting space ship. Quite lovely, and I really could see no difference initially in terms of overall image quality.

I also repeated this experiment with a quality refractor from my back yard.

Then, suddenly, two neurons in my visual processing center connected. The Pentax and the Takahashi eyepieces yielded the most creamy white neutral image of the Moon. The Nagler was just a twinge warmer, or more yellow. Took forever to notice it, but again once you do, you can’t unnotice it. In the absense of the other two eyepieces I’d have never said… my, that looks a tad yellow don’t you think? It always seemed quite white and clear before. I never before and I still don’t find this slight yellow cast objectionable because it really is at the edge of perception and you really have to have something to compare it to in order to detect it. On any given night with only my box of Naglers it’s never going to be an issue. In fact I repeated this experiment at home using one of my Esprit refractors on the Moon. Using the Nagler, I could not see the warm bias in the slightest… until I popped in one of the other two eyepieces and compared it immediately. It’s like two television sets in a department store next to each other with slightly different color settings. If they weren’t right next to each other, you’d never know.

The next difference was along the lunar limb. I’ve compared the Nagler to so many lesser eyepieces that had a green or violet fringe along the lunar limb that to me the Nagler had no fringe at all. It was clean. I learned here a new meaning of the word clean. There is actually a small green tinge to the lunar limb. Almost imperceptible, and again in the absense of eypeices that render nothing there at all, I could not detect it. Now however… I could not NOT see it. Razor thin and ghostly… and again not objectionable, but if you look for it, it’s there. If it where a photograph, it would be a tenth of a pixel wide! <sic>

Now, the Takahashi and Pentax are tied. Both render a sharp view, both have NOTHING along the lunar limb. The Pentax might edge out the Tak because it has such a wide field of view. Again, scrutiny… in imaging we call this pixel peeping.

In the Pentax, the center is excellent, and as you wander out to the edges, it’s also very sharp, and I had no complaints. Only after switching back and forth did I notice something subtle again. The Pentax is quite wide, and this is a wonderful feature. The cost is the slightest, slightest loss of sharpness away from the center.  Out away from the center, the image is sharper in the Takahashi than with the Pentax. Tiny details on the surface are popping out in the Takahashi that are just not as well defined in the Pentax, or the Nagler (the Nagler Type 2 was also pretty wide, and similar across the field in sharpness to the Pentax). These are the smallest features, and I’m talking about surface texture here, not craters and rilles, those all look equivalently sharp. But the tiniest surface… fingerprints… those were apparent in the Takahashi more so than the Pentax or Nagler.

Now, it’s a tough call because it was HARD to see the sharpness difference, and only by doing this side by side. The Pentax however was much wider… and there is something to be said for that as well. I remember this feeling the first time I looked through my 31mm Nagler type 5… in comparison to my Plossels. Even if the Plossels had been slight sharper (which they weren’t), I still would have preferred the Nagler’s field of view.

So, I’ll call the Takahashi and the Pentax somewhat tied in this regard. Do you want that last 3% of sharpness at the edges, or do you want a portal into outer space experience? I should mention here too that the Nagler also provided a pretty wide field, but falls behind on the technicalities of being slightly off on color, and having the tiniest color along the brutal naked edge of the Moon. Never-the-less, I gave away most of my original eyepieces some time ago, and am still quite happy with my Naglers. We are down to the nitty gritty here, and the differences are pretty small. Only if I were starting over, might I make some different choices.


The Pentax has a wide field of view like the Nagler, but has better color fidelity. The Takahashi beat them both in terms of sharpness, but only just slightly, and with a much smaller apparent field of view. To be fair, my Nagler’s are now two generations out of date, and with both Ethos and DeLites now on the market the design has improved and I don’t have one of them to compare. Judging by their prices, I’d expect them to be more on a par with the Takahashi or Pentax eyepieces.

I am sorry to have to return my loaner Pentax so soon and maybe I’ll pick one up next NEAF when I’m on my next astro-shopping spree. However,  you should not expect to see my collection of Naglers on Astromart anytime soon. 😉

Clear skies,


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The Surgical Strike

Let me start with… in my defense… the weather forecast was for “some rain”, and then a clear night.

This does not look promising for a night of astrophotography.

My backyard has limits when it comes to astrophotography. There’s just enough sky to get some R&D type work done, some proof of concept and equipment tweaking, and a little bit of sky to the East. But precious little sky at that, and way too close to Orlando Florida to be great for imaging beyond star clusters and narrow band emission targets (the Moon and Planets not withstanding).

Thankfully, I have a spot on some friends property down in Okeechobee county where a few of us have setup observatories. I recently sold my Sky Pod shed to make way for a small roll off roof, and so now I’m fibbing a little if I call it my observatory, but it’s at worst still a nice dark sky camp with a place to sleep, make meals, and clean up. It’s also in the middle of a God forsaken swamp… In the Florida Winter it’s a great place to spend up to a week or more at a time, but in the Summer it’s bug, frog, and… rain infested. Occasionally, the junkie needs his galactic photon fix, and I must go and brave the elements. These summer adventures we playfully call the “surgical strikes” at Stardust Ranch. You go down for a single night, trod through the mud, brave the bugs and make the best of it. Sometimes it’s even worth it!

The best guard dogs money can’t buy.

My last surgical strike was quite successful, due to a great stroke of luck. For not the first time ever, the forecast for the night literally changed between the time I left my house, and the two hour drive down to my camp. It poured raining the entire way there. A friend on site working on his own setup, texted me to tell me he was leaving, and that it was pouring down raining there too. When I finally got to less than a mile from our gate and alligator infested moat (and no, I am totally not making that up), I received a text that his remote observatory had lost power in the storm. Great. Technically I can image on battery, but I will not survive the night without AC or power in my little “hut”.

In an enormous leap of faith, I decided to wait it out. The power came back on and it did quit raining long enough for me to uncover my pier (which still stands where my dome used to be), and pop on my Paramount MX+ and Esprit 150 that I had brought down in the back seat. I run these now with a Raspberry Pi connected to the mount, and a buried Ethernet cable allows me to remote into the Pi from my little “space ship” shed a few feet away. Inside my little control capsule, I have air conditioning, a bed, etc. This is a very nice way to image, and stay away from the bugs and skunks that frequent the area in the night.

Stardust Ranch… worth the wait.

I got distracted by a programming issue (hey, it’s what I do), and hourly I’d check outside. After my initial break to setup, it rained until after midnight, and at 2 a.m. it was hazy and foggy and I knew it was a lost cause. However… nature called just before 3 a.m., and when I went outside, I saw it was quite clear. Hey, I don’t want to waste the whole trip, I should do at least a couple of nice Milky Way shots with my fast f/1.4 lens. The results were quite good and I walked around in the dark looking for different compositions and suddenly it hit me. I had a telescope all ready to go! All I had to do was uncover it and do a quick TPoint run and focus. 15 minutes later I was ready to go, and with only 1 and a half hours till astronomical twilight. This was stupid… I should just go to sleep I thought. Wait, I need some messier objects for my poster project, and listen… if you only have an hour to shoot something, make it a globular cluster!  You can get good results on these even with moderate light pollution and a Moon in the sky. Under a dark sky here, only an hours worth of data even at f/7 should be plenty.

I picked through a few while my TPoint model ran (it was after all, a new “setup”) for a few minutes, and selected M55. It seems quite large at my 1050mm of focal length, and I had my FLI ML-16200 with anti dew strips on the cover plate (I find I really need these in the swamp). With the dew heater on the front turned all the way up, I turned it loose with TheSkyX LTI and had it refocus between filters and run till astronomical twilight before starting to take some dark frames. Having very little time to setup for a lengthy TPoint model, I just did a series of two minute unguided exposures, and this was plenty of time for an individual sub.

Messier 55, a very large globular in the Southern sky and well worth shooting!

I set an alarm and took a 2 hour nap.  When morning twilight was bright enough, I took some twilight flats racing the rising sun before the sky got too bright. This was what I came down here for after all.

Surgical strike. Drove over 4 hours total, spent the night in the middle of nowhere and with only a couple hours sleep, all for a nice Milky Way shot and a single run on a globular cluster. Was it worth it? Yes. This is what makes us astrophotographers tick. This is also why we want to punch anyone in the nose who says “wow, you must have a nice camera” when they see one of our photos. Yeah, it was the camera that did all the work, sure. 😉

Clear Skies on your next surgical strike!





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You’ve Got Some Nice Data

Regardless of your craft or art form, the best way to know you’re improving over time is to look back at something you did a few years ago and feel a since of… Wow, I could do so much better than that!

Omega 2011

My original 2011 version of Omega Centauri.

I do this frequently, and it lets me know that I’m improving, or at least growing towards something I’m happier with in my skills (regardless of what anyone else thinks). I was recently cleaning up some old external hard drives and I came across some images from the 2011 Winter Star Party. This was the first year I had ever entered the astrophotography contest, and of course I lost. When I saw my old rendition of Omega Centauri, my present-day self with 8 more years of experience was horrified (this wasn’t actually even the worst). So GREEN!

I noticed however a file named “OmegaStacked.tif”, and I realized this was the original unstretched master. I had carefully calibrated, aligned, and stacked the data and here it was, ready for post processing all over again. My equipment was modest, at least by my current standards. An unmodified Canon Rebel DSLR, and a small Takahashi FC76 refractor I called “Vera” was riding atop a prototype of the Paramount MX. I had to focus by hand I recall, and my exposures weren’t very long. I don’t have the original information about how long my exposures were, or what my ISO was, but I had nice sharp stars when I did a quick screen stretch in PixInsight. I spent maybe 10 minutes on it, and the results were something my 2019 self was much happier with.

Better Omega Centauri

A second pass 8 years data on the same data set.

I then had an epiphany… my earliest mentors in astrophotography when looking at my images would say the strangest thing. “You have some nice data there”. Some would say “looks nice” in addition, and the best mentors would point out things I needed to work on. I know of one who I did not show this one too, that I’m sure he would have said something about the very strong green color cast.

Good Data

“Vera” on the first Paramount MX. Good data is… “Paramount” ;-).

Good data does not get stale. In 2011 I had the basics down well enough that I was getting good solid data to work with. This is an accomplishment on its own as getting good data is not trivial either. My mentors were complementing me on that, while not wanting to discourage me too much on my processing abilities.

It was some time after this that I stared more carefully archiving my image runs. I keep the raw data, and the calibration frames and occasionally I’ll combine old data with new, or just go back and revisit an object I recall I just wasn’t happy with. Perhaps a few years later, I can get something I’m happier with out of it. I recommend you do the same. We all start i the same place, and most of us continually improve!

Good data hunting,

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The Evening Show

Revealing the Universe Through Astrophotography

Addendum: This book is also now available on Kindle.

I just released on iBooks my first digital book, which is also my first book on Astrophotography. I’ve long been an opponent of self-publishing, and now that I’ve done it, does that make me a hypocrite? No, it means I’ve learned the error of my ways (technically to be a hypocrite, I’d have to self-publish AND STILL tell people that self-publishing was a dumb thing to do). Let me tell you how…

A long time ago in a career far far away, I wrote a book. I had some help, but I was the lead author of a best selling book (in its little niche) called The OpenGL SuperBible. It was originally published by Waite Group Press, and through the course of several editions and updates, eventually found a home at Addison Wesley. That book was great for my career at the time, and though it did not make me rich in sales, it opened a lot of very lucrative doors for me, such as an adjunct-professor spot at a local trade school as a teacher, and it got me out of the healthcare software business back into vis-sim and scientific visualization, which was the software development career I had originally envisioned for myself.

Writing a book is an incredible experience like none other in my career. Each edition once completed was followed by swearing to both the old gods and the new that I would never write another book. Then the 2nd edition came… the 3rd, and so on (I did finally turn loose of the reins with the 6th edition).

This book is certainly one of the highlights of my career.

Being an author does wonders for your self-esteem and confidence too, and bordering on arrogance, I was often full of advice for other would-be authors. Sometimes this was solicited… at other times not so much. I felt a huge burden to help my fellow man/woman, especially every time I heard the following:

“I’m self-publishing my book, so I can keep more of the profits”.

Poor fools, I had to save them. It was my moral obligation.

I’ve self-published software before, and the act of promoting the software is easily more work than creating it in the first place. Publishing is I’m sure the same way (I still believe this to be true). My opinion was that self-publishing is for people who don’t have a strong enough book to find a publisher, or people who don’t realize how much work it is to sell a product once it’s produced. Publishers, will make you famous. They will pay you, they will arrange book signings, they will put your book in catalogs, and most likely you will actually make far more money than if you’d published it yourself. They will open doors of opportunity for you that you never imagined, and even better once the book is done you don’t have to keep working to promote it yourself.

Went to a publisher, but made very little money for your book? You’d have made even less most likely if you had to pay to print and distribute the books yourself. Almost certainly.

Okay, so why did I self-publish? Why did I change my mind?

Firstly it was motivation. My first book was strictly a career move. It established credibility in an area of computer science and it got me jobs I wanted that I might not have been able to get otherwise. My motives were 100% financial and career oriented, and maybe a little ego. I did/DO love the topic I wrote about, and I don’t want to diminish the role that played in the quality of my work, or my commitment to it. I love to write too, make no mistake, and it was a natural thing for me to do, and I’ve even gotten better at it over the years. It was the smart thing to do. What about this latest book? Completely different motivations. Completely.

We are a way the Universe knows itself. Astronomy has always been my first love.

For starters, there is an artist side of me, and that artist was fighting to get out. I wrote The Evening Show purely because I had too. It was in me, and I was going to explode if I didn’t do it. Sure, I’d be thrilled if it did well enough to pay off a few debts, or buy some new toys, but that was far from my motivation. I simply had to do it. It was in the purest sense and artistic expression of mine and mine alone. Other authors and photographers have their own motivations, and I have mine. I’ve expressed this in my book, and if anything, it is a love letter to the night sky and the practice of astrophotography more so than it’s meant to be anything else.

Now, I did poke around and looked at a few publishing houses. I checked out their authors guidelines (I’ve done this before after all), and most/many said right up front, “We do not do coffee table/picture books”. My book is sort of just a picture book, with a bit of text, but I knew that it was going to be an uphill battle to convince anyone that they should take a financial risk with this. It was after all, my own expression of art. I could also see some editor/marketing person insisting that I have at least one page full of camera settings or something so they could put “learn from the master” or some other such nonsense on the back. That’s not the audience I was targeting… at least not this time<g>. In other words, I did not have a strong enough book to sell, so I published it myself! Ha ha… jokes on me.

Another aspect I liked about self-publishing was the electronic aspect. Getting my photos to print well is pretty tricky, and the idea of a whole book of color images that might come out looking pretty cruddy compared to what I saw on the screen did not sound appeasing. On an iPad, I knew everyone was going to get nearly the same experience that I was intending to present. I also remember what a huge deal it was just to get some color pages in my previous book, and again get them to come out right. Yep, I think I’ll skip that.

Now down the road, maybe some publisher will take an interest in this, but I’m not going to spend hours a day to hunt them down. I may also do a Kindle version or something down the road but for now it’s out on the Apple platform (was really easy to do btw) and the hardest part is done. We’ll see what happens in the coming months. I can also tell you I have at least three or four more books bursting to get out of me, some from an artistic standpoint, but there’s also a philosopher buried in there too wanting to be heard, and a teacher… so more books focused on “learning to do something” are also coming, but I had to get this one out of the way first. If you get the book, I hope you will enjoy it as much as I did in making it.

Clear skies!

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