36 replies to this topic

[Starman1]

Here is the 2018 version of the Eyepiece Buyer's Guide.

A few brands added (ATC and Oberwerk and Sky Mentor), and few meeting their demise (Zhumell, Levenhuk, etc.).

Total number of eyepieces is down, despite new additions to many lines.

Still quite a few.

[edit: there were a few formatting problems.  I've fixed them and reposted the spreadsheet below.]

 

EDIT:  Updated file as per Don's request.

Attached Files

•  2018 Buyer's Guide to Eyepieces.xlsx   200.78KB   5692 downloads

Edited by Jaimo!, 04 April 2018 - 06:14 PM.

[Joe1950]

As always, Thank You, Don!!!!

[Symui]

Thanks Don !

 

This is a great resource !!

[Jim Davis]

I was using your 2017 one today, and wondering when the 2018 one was going to arrive. Thanks!

[Castor]

Thank you Don!

 

A monumental work for sure!

[Starman1]

I'm a little upset at how much information is missing.

I don't understand why manufacturers think that someone buying an eyepiece wouldn't want some details about the eyepiece, like apparent field of view, for example.

Some of the information came from reviews and articles about the series instead of the manufacturer's site.

So I invite the community to improve the list--if you know some of the missing information, send me a PM about it.

Or if I left out a notable brand.

 

One decision I made in doing the list is that I simply didn't list all the eyepieces from some Chinese companies that only sell on eBay.

There are tons of small labels selling innumerable inexpensive Chinese Plössls, for instance.  I could easily have added 500-600 entries just for those.

And they come and go as stock fluctuates, so the list would be obsolete immediately.

And names change from month to month on many of them (Vite became Svbony, for example).

I was a little averse to listing KSON as a manufacturer, as I think they provide only private label stuff and only sell under that name on eBay.

But at least they have their own website.

 

I also did not include ALL the eyepieces on manufacturer's sites, since they are not sold directly to consumers.

It's also unclear whether some brands listed still exist (Knight Owl?) or whether the websites just happen to still be up.

And I added one series of eyepieces that won't be available till August (Explore Scientific 52°).

 

What's really unclear is why I keep the list up at all.

[CrazyPanda]

I'm a little upset at how much information is missing.

I don't understand why manufacturers think that someone buying an eyepiece wouldn't want some details about the eyepiece, like apparent field of view, for example.

Some of the information came from reviews and articles about the series instead of the manufacturer's site.

So I invite the community to improve the list--if you know some of the missing information, send me a PM about it.

Or if I left out a notable brand.

 

One decision I made in doing the list is that I simply didn't list all the eyepieces from some Chinese companies that only sell on eBay.

There are tons of small labels selling innumerable inexpensive Chinese Plössls, for instance.  I could easily have added 500-600 entries just for those.

And they come and go as stock fluctuates, so the list would be obsolete immediately.

And names change from month to month on many of them (Vite became Svbony, for example).

I was a little averse to listing KSON as a manufacturer, as I think they provide only private label stuff and only sell under that name on eBay.

But at least they have their own website.

 

I also did not include ALL the eyepieces on manufacturer's sites, since they are not sold directly to consumers.

It's also unclear whether some brands listed still exist (Knight Owl?) or whether the websites just happen to still be up.

And I added one series of eyepieces that won't be available till August (Explore Scientific 52°).

 

What's really unclear is why I keep the list up at all.

I had that same problem when working on my eyepiece planner site. I would find an eyepiece series and there would be almost no information about it. No field stop, no apparent field, no eye relief etc.

 

I'd have to scour the web for info and reviews about it. 

[dgordontx]

Here is the 2018 version of the Eyepiece Buyer's Guide.

A few brands added (ATC and Oberwerk and Sky Mentor), and few meeting their demise (Zhumell, Levenhuk, etc.).

Total number of eyepieces is down, despite new additions to many lines.

Still quite a few.

[edit: there were a few formatting problems.  I've fixed them and reposted the spreadsheet below.]

 

EDIT:  Updated file as per Don's request.

calculations are off...

 

Cell R9 should be "=A3"

Cell S9 Should be "=B3"

[Starman1]

??

A3 and B3 are blank.

You add figures to the fields A2 and B2.

R9 is a dollar amount calculated from the hidden field Q9

S9 is a hidden field to help calculate the fields I9 and M9

Your spreadsheet must be completely scrambled.

I'd download it again.

[Adun]

I'm thinking it might be useful to make a web app to search this data.

 

I mean something like:

 

You give it a scope (aperture + focal ratio), and search for eyepieces that give a range of magnification or TFOV or exit pupil.

 

With the amount of clouds I'm having lately, I might have enough free time to tackle at something like it.

[aeajr]

Guys, remember that Don is a vendor, so if you are buying eyepieces, give him a chance at your business.

https://www.eyepiecesetc.com/

[Starman1]

I'm thinking it might be useful to make a web app to search this data.

 

I mean something like:

 

You give it a scope (aperture + focal ratio), and search for eyepieces that give a range of magnification or TFOV or exit pupil.

 

With the amount of clouds I'm having lately, I might have enough free time to tackle at something like it.

Couldn't you achieve the same thing with a spreadsheet sort?

[CrazyPanda]

I'm thinking it might be useful to make a web app to search this data.

 

I mean something like:

 

You give it a scope (aperture + focal ratio), and search for eyepieces that give a range of magnification or TFOV or exit pupil.

 

With the amount of clouds I'm having lately, I might have enough free time to tackle at something like it.

Checkout https://eyepieceplanner.com

 

I did that very thing. 

 

You enter your telescope info (several telescopes if you want), it computes all that data for you, and makes each column searchable, sortable, and filterable. 

 

You can do filtering like:

 

* ~value (matches approximately that number +/- 10%)

* min-max (include any eyepiece in the given range)

* > value (include only eyepieces greater than or equal to value)

* < value (include only eyepieces less than or equal to value)

 

You can then select different eyepieces to compare them side by side for one telescope, or compare multiple telescopes side-by-side for one eyepiece by clicking on the eyepiece row.

 

If you create an account, it will save and persist your telescope information. 

 

The data is not based on the buyer's guide though and is probably not quite as accurate in some places. It also contains discontinued eyepieces in case you come across something in the classifieds that you want to see how it slots in with other options.

 

The eyepiece region/cost thing is still very much in progress, but the calculation stuff is done.

Edited by CrazyPanda, 18 April 2018 - 05:04 PM.

[Adun]

Checkout https://eyepieceplanner.com
 
I did that very thing. 
  
You can do filtering like:
* min-max (include any eyepiece in the given range)
 
You can then select different eyepieces to compare them side by side for one telescope, or compare multiple telescopes side-by-side for one eyepiece by clicking on the eyepiece row.

It's very nice!

Filtering by TFOV by ranges wasn't intuitive (typing 1.4-2 to mean the range) I only tried because of what you posted, but perhaps a tooltip or something could make that feature more "discoverable".

So how do you keep the list up to date? Which is more accurate, the excel or the planner?

Edited by Adun, 18 April 2018 - 07:33 PM.

[CrazyPanda]

It's very nice!

Filtering by TFOV by ranges wasn't intuitive (typing 1.4-2 to mean the range) I only tried because of what you posted, but perhaps a tooltip or something could make that feature more "discoverable".

So how do you keep the list up to date? Which is more accurate, the excel or the planner?

Yeah agreed about the discoverability of some of that functionality. Haven't given it a full UX pass yet. 

 

I keep the list up to date as I see new lines introduced or discontinued, or stumble upon new, tested information about particular eyepieces. My guess is that excel sheet is more accurate at this point - especially for popular eyepieces without a lot of stated manufacturer specs. There's also some conflicts. The stated eye relief of some Agena Starguider Dual ED eyepieces is different from the stated eye relief of some AstroTech Paradigms, even though they're the same eyepiece. Hard to know which one is correct without doing actual measurements. 

 

One other problem is that some eyepieces do not state the field stop, so I have to use flawed apparent field / magnification calculation for those eyepieces. If a field stop value is provided, then I use the fieldstop formula: field stop diameter / telescope focal length * 57.3. So if you sort by true field of view and limit it to 1.25" eyepieces, you'll see that 40mm eyepieces are often at the top, even though that's likely not true. I've thought about adding an artificial penalty to any eyepieces without a stated fieldstop, just not sure what it should be.

Edited by CrazyPanda, 18 April 2018 - 10:51 PM.

[lakewoodpaper]

​This is so awesomely amazing! Thank you!!!

[lakewoodpaper]

Thank you Starman1 / EyepiecesEtc.com and CrazyPanda, you are the best! That must have been a ton of hard work and time to do and it is very much appreciated!

​

​Starman1, I just discovered your wonderful website, will be ordering from you soon.

[Simon B]

Cheers Don

[Gerald_db]

Thanks so much. I need to upgrade the KE eyepieces that came with my Celestron 130 and as I am nearly 60 with reasonable astigmatism and hence waer glasses I have been hunting for a list of eyepieces that have good eye-relief. Don't want to spend a bomb but desperate for something that works with glasses on especially at the higher magnifications. 

[Starman1]

Sort the list and look for 20mm of eye relief or more.

There are LOTS of choices, now.

[Napp]

Awesome!  Thank you, Don.

[idrivea911]

Newbie here. Just browsing your sheet, and wondering what the f/ratio is?

[aeajr]

Focal ratio is the relationship between focal length and aperture of the telescope.

 

So a 100 mm aperture scope with a 1000 mm focal length would have a focal ratio of F10.

 

Focal Length / Aperture = FR

 

A Celestron NexStar 8SE has an optical tube with a 2032 focal length and a 203 mm aperture

 

1800/127 = F10

 

This becomes useful when calculating exit pupil from the eyepiece.

 

FL Eyepiece / Focal Ratio Scope = Exit Pupil   

 

 

A very good discussion, by Al Nagler, about eyepieces and magnification for those who want to go a little deeper. He discusses our eyes, our telescopes, focal ratios, exit pupils, the atmosphere and things related to choosing magnification.   A good read and not too technical.  It is a general discussion and not specific to any eyepiece or any brand of eyepiece.
http://www.televue.c...page.asp?id=102

Edited by aeajr, 27 June 2018 - 09:54 AM.

[Ursa Minor]

Thanks very much for creating this list, it must have taken quite some time to compile.

[Starman1]

The original was created in 2004, when there were over 2000 eyepieces available.

Since then, it's been more about adding a few here and there, but mostly editing.

The numbers of eyepieces have fallen except for inexpensive Chinese clones, which have proliferated.

The list would double in size if I included every transitory brand found on eBay.

But those entries would fluctuate wildly over a month or two, so I've mentioned the brand, but left out the items.