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A Comprehensive Database of 300 2" Inch Eyepieces

cshahar

By cshahar
in Discussions - Eyepieces

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cshahar

cshahar

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Hi Everyone:

Well, I decided to beat the winter doldrums by creating a database of 300 2” eyepieces, most of which are currently on the market. Initially I was doing it to educate myself as to what is available. It then took off or got out of control, depending on how you look at it. I believe this to be the most comprehensive database of 2” eyepieces. There are two or three other Excel spreadsheets out there, but they are either somewhat dated or don't contain as many fields. While I don’t have as much experience with eyepieces as some of the people in this group, I have been working as a researcher for 25 years, so I like to organize and tabulate data. Anyways, I am pretty excited about the results.

This may end up being a useful informational resource. But it does need a bit of tweaking. If there is enough interest I would like to maintain this database as an ongoing project. But I need some help. I would appreciate getting feedback from members. From people who have a long experience with eyepieces I would appreciate getting help regarding filling in some of the blanks in the database (for instance, info about country of manufacture, quality rating, weight, etc.). From anyone who has any of the eyepieces listed I would really like to fill in some blanks, particularly with regards to weight, but in relation to any other field as well. Sometimes manufacturers and distributors are rather cagey about specifications such as weight, eye relief, or country of manufacture. But please make sure you are very certain of the information you supply!

Note that a few of the models are no longer available through mainstream commercial outlets. But the great majority are.

Please send me revisions indicated in red font or yellow highlight so I will spot them easily. You can also email me directly:  charles19@sympatico.ca

Here are the fields: Brand, Model, Type, Focal Length, Elements, FOV, Eye Relief, Weight (lb), Weight (g), Price (USD), Price (EUR), Quality Rating, Country of Manufacture, Clone Group.

Please note that I sort the data in 4 different ways (see tabs at bottom of spreadsheet).

Here are some more comments about the fields:

Brand: This is probably the only straightforward field regarding this exercise.
Model: Whatever was specified by the distributor / manufacturer.
Type: e.g. Plossl, Konig, Super Wide Angle, etc. I might need help in a few cases where the manufacturer wasn’t up front.
Focal Length: Also a very straightforward field.
FOV: I specified what the manufacturer claimed. There might be differences of opinion here. But I will stick with the manufacturer’s specs.
Eye Relief: Difficult to get information for some models. Again, differences of opinion exist here regarding the difference between stated and actual.
Weight: Ugh. My God. This was a very difficult field for some models. Would you mind sending me some weights (preferably in grams but I would accept ounces to within 2 decimal points)
Price: I give two prices (USDs and Euros). please note that I was least interested in this field. There is a wide variability here among different distributors. I generally ignored special sales. EBay or Amazon did not count.
Quality Rating: On a scale of 1-5. I am either foolhardy or brave to include this field. It is derived from two points of information: reviews and cost. Please do not feel insulted if you think I under-rated your eyepiece. I would VERY much like to get the opinions of people on this one, particularly observers with much eyepiece experience.
Country of Manufacture: I need your help here. It demands a knowledge of the history of eyepiece manufacture, which I have only a limited sense about!
Clone Group: I would be curious to know what you think here. I did my best, but this was one of the more difficult fields to achieve accuracy in.

I hope you all find this to be a worthy and worthwhile exercise. I certainly enjoyed the process. If there is sufficient excitement about this I would be happy to produce a tweaked version. Thanks!

-Charles

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cshahar

cshahar

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Thanks everyone! It did take a couple of months to put together.

Don Pensack's database doesn't actually look at quality, country of manufacture, or clone groups. These are actually the most difficult factors to quantify!

-Charles

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John

John

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Thats a very comprehensive piece of work Charles. As a self-confessed "occularholic" it's quite a fascinating collection of data.

The clone grouping issue is a tough one because some brands use the same optical layout but have comissioned a body style that is unique. You can make an educated guess based on the specifications of the eyepieces and, if you get a chance to look at them, by things like the lens retaining rings, lens diameters, coating appearance etc, but it's not a precise science ! I strongly suspect that the brands would rather we did not look to far into this in some cases :rolleyes2:

William Optics put a smile on my face by engraving 101 degrees on their XWA 9mm eyepiece which is clearly, having used them both, exactly the same as the Skywatcher Myriad 9mm :smiley:

Glen Speers of Antares caused some confusion with the W70 range by using heavily re-clothed Skywatcher UWA eyepieces for some of the focal lengths and then changing the focal lengths slightly :rolleyes2: . Inside some of those nice alloy bodies lurk bog standard Skywatcher UWA's.

One piece of information that I find very useful but is hard to acquire outside of a review or the excellent Tele Vue web information, is the positioning of the focal plane of the eyepiece. There is really quite a lot of variation in this and, in extreme cases, it can make the difference between an eyepiece being useable in a scope and not. 

Good work and thanks for posting this :smiley:  

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John

John

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I think you are brave to invite us to give you a quality rating for our eyepieces ! - mine are all 6's of course :grin:

Brilliant!!

I look forward to looking at this file properly very soon- but not tonight as I'm going to see Saxon live right after work:-)

Dave

Hey - I saw Saxon back in the 1980's in Bristol. Great band :grin:

Is Bif Byford still going strong ?

Hope it's a good one Dave :smiley:

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YKSE

YKSE

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Thanks Charles, that's great work.

As I'm finicky and have OCD about weight,  there may be some numbers need to be adjusted, the MV 24mm seems to be the 82 degree one, weights of 26mm and 20mm Naglers might be a little off too.

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Scosmico

Scosmico

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Great work Charles. Very nice that you put quality. It is a criteria that can be technical, but also include personal preference.

For this reason I would like to hear how you got the difference between the 3.5 for the ES 100 and the 5 for Ethos?

I have read reports that quality wise they a bit close than that.

regards

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cshahar

cshahar

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Hi Everyone:

Just came home from work so I can respond.

John, thanks for the kind words. I quite know about the difficulties regarding defining clone groups. And I totally agree about the brands preferring that we didn't look too closely. In some cases the body may look almost identical but the optical quality may be very different. But only someone who has been attentive to eyepieces for a long time would know. Which is why I really would like to benefit from your experience..Interesting about the Antares W70 series. I shall research it more thoroughly.

YKSE: Please do update me on any weights that you find are a bit off. I am very interested in getting these figures right, because I too am picky about weight.

Scosmico, to be perfectly frank, any eyepiece 3.5 or above I consider excellent. What I am trying to say is that there is not much difference between 3.5 and 5. That is why so few eyepieces were rated so highly. I used the Ethos as the standard. Whether I should have given the ES 100 a 3.5 or 4.5 is a fair question. The reviews suggested that the eyepiece, while close to the Ethos was slightly below. However, I am open to revision.

-Charles
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John

John

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Charles,

I reckon the quality rating issue could end up detracting from the value of the data. Having taken a keen interest in eyepieces and their performance over the past couple of decades I reckon it's such a variable and personal matter then you will rarely reach concensus on a single eyepiece, let alone 300 of them !

The specifications though are quantative rather than qualitative and can be determined, albeit requireing some further research in some cases.

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