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Eyepiece Resolution World Cup


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The Extremely Official, O.F.L.I.-Certified, Eyepiece resolution™ World Cup!

By James Barnett, Dan Parker and Jeff Cooke

One winter evening in a fallow field on a small Sonoma, California, farm two gentlemen in their middle years were passing a few quiet hours looking up. One man says "Hmm…this is interesting." The other doesn’t hear him, being way up a ladder looking through a criminally wide field eyepiece at photons collected by a shockingly curved and immodestly large and massive mirror. The man who spoke is placing one eyepiece in the diagonal of a small refractor, observing for a few minutes, then replacing that eyepiece with a second and observing for a few minutes more. He speaks again, this time louder: "Dan, I want you to come and take a look at this and tell me what you think." Clatter, clatter, clatter. The other man, Dan, climbs down from his ivory tower. "What?" he says. The first man, Jim, says: "I want you to look at the Double-Double through a couple of eyepieces and tell me what you think about them." Middle-years memory is a frail and imperfect device, but I think Dan muttered something about "…probably some narrow field…ancient…thimble-apertured…not an Ethos…blah, blah, blah…"

Jim loaded the diagonal with one of the eyepieces and Dan dutifully took a look. After a long moment Dan sits back and Jim replaces the eyepiece with another. Dan spends another long moment or two observing and then sits back and looks at Jim. Jim says: "Did you see a difference?" Dan with his customary eloquence says: "The first one #$!@&!." Jim nods and gravely replies: "Yep." [Note: I’ve taken artistic license here. Dan was (probably) more civil in his comment, but for the sake of the story, I like it better this way. As a consequence, I ask that you please don’t stalk Dan.]

That was the genesis of the Eyepiece resolution™ World Cup concept. The two eyepieces in question shall remain nameless as far as the Double-Double vignette above goes, but both are well-loved by a sub-segment of the CN community. Both are frequently praised for their superb "resolution, contrast, transmission, sharpness,..." etc., etc. One is considered quite expensive for what it is, the other is considered a bargain. One is a many decades old design, the other is a very modern design. Most importantly, both are represented in the resolution™ World Cup and take their lumps and laurels accordingly. Read on.

I. The Concept.

The World Cup concept that emerged from further discussions was to (a) use two similar small aperture scopes of eyepiece-forgiving specifications in an as near identical a configuration as possible, with (B) a host of shorter focal length eyepieces in the 7mm to 8mm range to © to view an object that, given the rigors of the field including atmospherics, would pose a greater "challenge" to the scope-eyepiece combination than Epsilon Lyrae which inspired the concept, and ultimately allow differentiation between the eyepieces.

Rather than going deep into the "science" of why one eyepiece might have performed differently than another under the conditions of the contest, we resolved to simply provide the "what" as in what we saw, and leave the "whys" and "what ifs" to others who are interested in and competent to analyze such things. The winner would be that eyepiece that bested its peers in a group round, a semi-final round and a final round.

We settled on the following parameters: two observers, two 102mm f/8.6 Televue APO doublets, two Astro-Physics Maxbright diagonals, twenty eyepieces in the 7mm to 8mm focal length range, one target (Theta Orionis – the Trapezium), a simple set of criteria (on axis, how many Trapezium stars are seen). Each of the twenty eyepieces was assigned a unique number (1 through 20) and a random number generator was used to re-order the twenty. The re-ordered eyepieces were then separated unto groups; the first five forming Group A, the second five forming Group B and so forth. There were four groups of five eyepieces in all.

O.F.L.I. is the local astronomy group I associate with. O.F.L.I. stands for the "Off Fisher Lane Irregulars." Fisher Lane is a small gravel road in central Sonoma, California. It is dotted with farms, vineyards, and the occasional farm house. It has no street lights. It’s flat. It’s where Dan and his family live. It’s where the other folks and I who elect to associate with O.F.L.I. observe frequently. I bring up the organization not to proselytize but because its character played a huge role in the format we chose for the World Cup. You see, there’s no formal membership, no dues, no officers, no pomp, no process, no red tape and no pressure. It’s more of a "disorganization" than an "organization". Folks join O.F.L.I. by hearing about it, contacting Dan who is the host, and showing up at a scheduled observing session. People travel from within a 200 mile radius to come to the Farm as the site is known. O.F.L.I. is really a collection of work-a-day refugees who want a quiet dark place from which to observe with other like-minded folks without any expectations or requirements. The character of the group is whimsical, informal and sometimes irreverent.

Rather than trying to come up with a format that "fairly" tried every eyepiece against every other eyepiece in the test, we elected instead to adopt a format that would preserve the mystery and leave the door open to speculation about how an eyepiece might have done if it had been grouped differently or whether there was any agenda being advanced by the organizers. The natural analogue was sports - regular season contests, play-offs and final championship game. I could think of a no more colorful, high-drama, high-intrigue sporting event than the FIFA World Cup. The World Cup occurs every four years, it is global in scope. In almost every World Cup there are allegations of unfair match-ups, corruption of officials, divine intervention, you name it. The entire range of human emotion is displayed, and every vice and virtue showcased. A rich pageant worthy of emulation by a trio of capricious O.F.L.I. blokes.

II. Testing Protocol and Scoring System.

(A) Testing Protocol.

The following is a condensed version of the testing protocol document used by Dan, Jeff and I in conducting the test. This describes the testing process employed for the evening. The scoring was done in accordance with the scoring system that follows the testing protocol. This is useful in critiquing the methods, but not essential to understand the scores. If you’d rather get to the substance of the report, skip this section II(A), read the scoring system in Section II(B) and then plow into the good stuff.

TESTING PROTOCOL

Roles:

Observer #1 = Dan (cuzimthedad)
Observer #2 = Jim (jrbarnett)
Proctor = Jeff (MakFun)

Testing Steps:

There are 4 groups of 5 eyepieces each. The Proctor will select one of the boxes (A through D) as he sees fit. The following Stages will be repeated for each eyepiece Group.

FIRST ROUND

Within the selected Group the Proctor will start with the FIRST listed eyepiece for that Group and place it in Observer #1’s diagonal. He will then place the FIFTH eyepiece in the Group in the diagonal of Observer #2. He will then start the timer and direct the Observers to begin observing. The Observers will have up to two minutes to focus and determine a maximum star count for that eyepiece. Upon either (a) indication from the Observer that he has finished with the eyepiece or (B) the end of the 2-minute period allotted for the Stage, each Observer will report his score for the tested eyepiece to the Proctor who will record it on that Observer’s score sheet.

Then, the Proctor will then place the FIRST eyepiece in the selected Group in the diagonal of Observer #2. He will then place the SECOND eyepiece in the Group in the diagonal of Observer #1. He will then start the timer and direct the Observers to begin observing. The Observers will have up to two minutes to focus and determine a maximum star count for that eyepiece. Upon either (a) indication from the Observer that he has finished with the eyepiece or (B) the end of the 2-minute period allotted for the Stage, each Observer will report his score for the tested eyepiece to the Proctor who will record it on that Observer’s score sheet.

The Proctor will continue in this manner until each Observer has scored each eyepiece in the chosen Group. Thereafter another Group box will be selected and the same testing procedure followed until scores are obtained for each eyepiece in that Group. These steps will be repeated until all eyepieces in all Groups have received first round scores.

FIRST ROUND SCORING

Upon completion of the first round a numeric score from 5 through 0 will be assigned to each Observer’s score for each eyepiece, 5 denoting that all 6 stars (A-F) were seen constantly and 0 denoting that only A-D were seen constantly and that E and F were invisible. A perfect score would be 10 representing a 5 score from each Observer. Details regarding the scoring system are in the section following this one.

The highest scoring eyepiece in each Group will be declared the Group winner. In the event of a tie within a Group, the Proctor will conduct an open (i.e., non-blind) observation of the Trapezium with each of the tied eyepieces and will assign a score to each using the same scoring method used by the Observers. The eyepiece receiving the highest score from the Proctor will be declared the Group winner. If any eyepieces remain tied after the Proctor’s scoring, the parties (Observer #1, Observer #2 and the Proctor) the winner among those eyepieces that are tied will chosen by drawing lots from a hat. The Proctor will prepare paper s****s with the name of each eyepiece that are tied and place them into a hat. Observer #1 will draw the winner from the hat.

SECOND ROUND (Semi-Finals)

Observer #1 will compare the winner of Group A against the winner of Group D. Simultaneously Observer #2 will compare the winner of Group B against the winner of Group C. Then, the roles will be reversed and Observer #1 will compare the winner of Group B against the winner of Group C while Observer #2 compares the winner of Group A against the winner of Group D.

The Proctor will load the Group A winner into the diagonal of Observer #1. The Proctor will load the Group B winner into the diagonal of Observer #2. The Proctor will then give each Observer up to 2 minutes to arrive at a score for the eyepiece. The Proctor will record the reported score on the appropriate score sheet.

Next, the Proctor will load the Group D winner into the diagonal of Observer #1. The Proctor will load the Group C winner into the diagonal of Observer #2. The Proctor will then give each Observer up to 2 minutes to arrive at a score for the eyepiece. The Proctor will record the reported score on the appropriate score sheet.

Thereafter, the above steps will be repeated but each Observer will compare the other pair of eyepieces (i.e., Observer #1 will compare the winner of Group B against the winner of Group C and Observer #2 will compare the winner of Group A against the winner of Group D.

SECOND ROUND SCORING

As with the First Round, upon completion of second round a numeric score from 5 through 0 will be assigned to each Observer’s score for each eyepiece. The highest scoring eyepiece in each match-up (A-D and B-C) will be declared a semi-final winner for that match-up. In the event of a tie within a semi-final match-up, the same tie-breaking procedures employed in the First Round will be followed.

THIRD ROUND (Finals)

Observer #1 will compare the winner of the A-D match-up against the winner of the B-C match-up. Then Observer #2 will compare the winner of the B-C match-up against the winner of the A-D match-up.

The Proctor will load the A-D match-up winner into the diagonal of Observer #1. The Proctor will load the B-C match-up winner into the diagonal of Observer #2. The Proctor will then give each Observer up to 2 minutes to arrive at a score for the eyepiece. The Proctor will record the reported score on the appropriate score sheet.

Next, the Proctor will load the B-C match-up winner into the diagonal of Observer #1. The Proctor will load the A-D match-up winner into the diagonal of Observer #2. The Proctor will then give each Observer up to 2 minutes to arrive at a score for the eyepiece. The Proctor will record the reported score on the appropriate score sheet.

THIRD ROUND SCORING

Upon completion of third round a numeric score from 5 through 0 will be assigned to each Observer’s score for each eyepiece, just as in the prior rounds.

The highest scoring eyepiece (either the A-D winner or the B-C winner) will be declared a final winner. In the event of a tie within a final match-up, the same tie-breaking procedures employed in the First Round will be followed.

(B) Scoring System.

Eyepiece performance on the Trapezium was scored using a 6 point scale (zero through five) as follows:

Trapezium A though F visible constantly – 5 points
Trapezium A through E visible constantly with F winking in and out – 4 points
Trapezium A through E visible constantly but F invisible – 3 points
Trapezium A through D visible constantly with E and F winking in and out – 2 points
Trapezium A through D visible constantly with E winking in and out and F invisible – 1 point
Trapezium A through D visible constantly but E and F invisible – zero points

Originally we had omitted a score for "Trapezium A through E visible constantly but F invisible" and discovered the omission during the scoring of Group A eyepieces. After a brief caucus the above 6-point system in place of the original 5-point system was adopted and an additional column was added to the score sheets to cover the omitted scenario, and the testing protocol was amended accordingly.

During the initial group rounds each observer determined a score for each eyepiece within a group and the total score for each eyepiece within a group was calculated by adding each observer’s scores for each eyepiece. The eyepiece with the highest cumulative score within each group was declared the winner and matriculated to the semifinal round.

III. Challenges.

The Trapezium is an interesting target. It consists of a multiple star system comprised of young hot blue suns embedded in a matrix of illuminated nebulosity. The presence of nebulosity reduces contrast making resolution of the component stars more challenging than their respective separations would suggest. The principle stars A through D are much brighter than the next two member stars the system, E and F. Two of the principal four stars, A and B are variables. The following image was created by manipulation of a public domain Hubble Space Telescope image of the Trapezium:



In case you are having a difficult time reading the labels, beginning from top left and going clockwise they are: B, E, A, C, F and D.

Magnitudes of the labeled components are as follows:

A = 6.7 to 7.5 (variable)
B = 8.0 to 8.5 (variable; eclipsing binary)
C = 5.1
D = 6.7
E = 10.3
F = 10.2

The four main stars are an easy split in almost any telescope. For reference the A-B separation is ~8.7". The C-D separation is ~13.3". The more challenging targets are E and F. The A-E separation is ~4.5". The C-F separation is ~4.2". Ordinarily you wouldn’t expect a 4.5" or 4.2" double star that difficult to split in a 4-inch refractor. The huge magnitude disparity between A and E, and C and F, however makes these chancy splits in a 4-incher. One seasoned double star observer and respected author suggests that under good seeing conditions a 100mm telescope ought to be able to resolve two stars that differ by four magnitudes so long as they are separated by 2.6" or more. The magnitude delta between C and F is a whopping 5.1 magnitudes. Extrapolating from the above rule of thumb, I would estimate that stars five magnitudes different ought to require a minimum of 2.9" separation for resolution in a 4-incher. The contrast-reducing nebulosity likewise ups the ante a bit. Throw in less than perfect seeing, and you have a challenge object in a 4-incher.

On the test night, Friday, January 16, 2009, I suspect that A was near its minima. It was noticeably similar in brightness to D. This probably helped on the A-E splits. Had A been a magnitude or so brighter, the raw scores might have been lower.

In addition to the challenges posed for the equipment by the target itself, other legitimate concerns regarding the format and execution of our testing emerged from discussion and are worth commenting on.

(A) Seeing Variability.

Spying Trapezium E and F is often described as a test for good seeing. Peruse the double star forum on CN for posts regarding the Trapezium and you’ll see what I mean. Folks in geographies with lousy seeing have a tough time seeing E and F in 8" scopes. Other folks with better conditions see E in scopes as small as 70mm. When the World Cup concept was discussed in the CN Eyepieces forum, several experienced observers expressed concerns about using the Trapezium to differentiate eyepieces. The main concern was that under perfectly still conditions any eyepiece that is diffraction limited on axis (which almost certainly every eyepiece in our list is) ought to render all 6 stars in the Trapezium. Conversely, under less that perfect seeing, changes in atmospherics throughout the night might impair detection of E, F or both in eyepieces that would otherwise render these targets. The night before the shoot-out Dan and I performed a preliminary set of observations of the Trapezium using an Antares 6" f/6.5 achromat with a couple of non-test eyepieces, a 6mm TMB Planetary and an 8mm Ethos. Seeing was horrible. A through D were bloating and wavering from second to second, and E and F were invisible in both eyepieces. Had this poor seeing extended to the night of the test, it would have been a short test. We could have given all of the eyepieces a zero on our scale (i.e., A-D seen constantly; E and F invisible) and called it a night. Fortunately our test night was blessed with some of the best seeing we’ve had in months.

Mindful of concerns about seeing variability, we adopted a couple of measures intended to mitigate the effects of changes in seeing on the ultimate results. First, by confining first round comparisons to eyepieces within a group of 5, and limiting each observer’s time with each eyepiece to 2 minutes, each observer’s observations with each eyepiece within a given group was conducted within a fairly short time frame; I would estimate that none of the first round group observations lasted more than 20 minutes. With the exception of eyepiece #5 in each group which I started with and Dan finished with, my observations with a given eyepiece occurred within a couple of minutes after Dan’s observations with that same eyepiece. Next, by cumulating scores to pick group winners, seeing changes that occurred between one observer’s observations and the next were "averaged out."

Despite these measures, the raw scores do suggest that seeing varied more during certain portions of the testing than others. Early on you’ll see that Dan and I may have scored certain eyepieces extremely differently. Dan might have given an eyepiece a score of 4 and a couple of minutes later I might have given that same eyepiece a score of 1 or 2. Later in the evening the consistency between Dan’s scoring and mine tightened up. Based on the raw data the most consistent scoring occurred in the semi-final and final rounds. Seeing remains one potential spoiler for our data. It is possible that eyepieces receiving low scores from both observers suffered not from lower quality but rather poorer seeing. I don’t think this is the case because the top scoring eyepieces retained consistently high scores throughout the entire evaluation, including group rounds, semi-finals and finals. Getting lucky with seeing during a five or six minute period during is plausible. Getting similarly lucky with the same eyepiece in both the semi-finals and finals is less plausible.

(B) Semantics.

We originally titled this evaluation "The Eyepiece Resolution World Cup." Use of the term "resolution" drew considerable criticism. Several knowledgeable observers posited that seeing Trapezium E and F in theory would not really be a test for resolution. A 4-inch scope ought to be able to resolve targets with such wide separations as the A-E and C-F separations no matter what 7mm to 8mm eyepiece is used. It was suggested that we supplement the field testing with daytime testing using white-on-black USAF resolution targets or with currency. We discussed this, but declined to pursue such testing for reasons discussed below.

Rather than resolution it was also variously suggested that our evaluation might technically instead be showing contrast, sharpness, or some other characteristic that might or might not be related to resolution. My own feeling is that testing eyepieces for isolated characteristics like sharpness, contrast and resolution in a laboratory is fine if you want to know what those things look like in isolation, in a laboratory. Unfortunately (or fortunately, depending on your perspective) few of us spend much observing time in a laboratory looking at laboratory type targets. In the field at night with dynamic conditions, luminous targets, inconsistent backgrounds, inconsistent luminosities, etc., I find it very difficult to ascertain whether I’m able to pick out a detail in one eyepiece but not in another because (a) my eyepiece has superior resolution, or (B) my eyepiece has superior sharpness, or © my eyepiece has superior contrast, or (d) a combination of one or more of these characteristics, or perhaps due to some other factors entirely.

Rather than try to attempt what Dan and I didn’t feel we were competent to or patient enough to complete, we instead made a decision to revise the title of the article and substitute "resolution™" for "Resolution". Rather than trying to determine which characteristic in a strict, technical sense was responsible for showing us more, we instead chose to go with the plain English meaning of "resolution" rather than the technical and scientific meaning. Ironically certain dictionary definitions of "resolution" resort to other terms like sharpness. In any case, for purposes of this report "resolution™" shall simply mean "the act or process of separating the Trapezium into constituent parts." That is rather than a characteristic of the eyepiece, the term describes the action of using the eyepiece to accomplish the stated task. We’ll say what we were able to see using each eyepiece on the chosen target. We’ll leave it up to you, the reader, to speculate on why we were able to see more using some eyepieces than others.

© Lack of Adequate Sample Size.

This concern is a very interesting one. There are bound to be variations between examples of the same type of goods. That is, it is almost certain that not all 8mm TMB Planetaries, 7.5mm Celestron Ultimas and 7.5mm Takahashi Les are created equal by the manufacturer. There are any number of ways one unit might be made better or worse than most of its peers. A few of the possibilities are differences in batches of raw materials, flaws in coatings, less accurate glass work or less fine polish, etc., etc. It was suggested that no matter what the testing format test results of a single example of a particular eyepiece might not be translate to other examples of that same eyepiece. You might have an abnormally good or abnormally poor example. I completely agree, though I am tempted to believe that the more an eyepiece costs, the more rigorous the quality control measures used in its creation. Presumably all that extra cost at least partially reflects increased manufacturing costs, a portion of which is probably extensive quality control testing. Because I don’t know for certain, however, how any of the eyepieces in this test are made, I’ll leave that thought as a suspicion rather than state it as a fact.

Whatever the case, without testing multiple samples of each eyepiece tested we have no way of knowing whether any of the units we tested are better than average, average or below average examples of their design. So should this stop the show? Of course not. I’ve never seen any report, amateur or professional, that tests multiple examples of anything being tested, whether telescopes, mounts or eyepieces. Imagine trying to test five TEC-140 OTAs rather than one or twenty 31mm Televue Nagler Type 5s rather than one. The additional time alone would make such testing uneconomic or untenable. Combine this with the fact that amateur testing more often examines items owned by the tester and his or her friends and colleagues, and the expense of assembling more than one example of each item tested would be prohibitive. In our case, beyond time and expense issues, we would also have to contend with rarity issues in some cases. For example, assuming expense were no object, we could easily purchase fifteen to twenty units of most currently produced eyepieces like the 7mm Televue Nagler Type 6, 8mm Televue Plossl, 7mm Pentax XW, 8mm TMB Planetary, 8mm Edmund RKE, etc. The odds of us being able to assemble fifteen to twenty out-of-production eyepieces like the 7mm Meade Research Grade Orthoscopic, 7mm Pentax SMC Orthoscopic, 7mm Takahashi MC Orthoscopic, 7mm TMB Supermonocentric, etc., are extremely slight.

Given that virtually no astronomy gear reviews published today, whether amateur or professional, address the inadequate sample size issue, and yet we all read such reviews and often act based on the conclusions stated in them, this particular review is no better or worse than any other reviews with respect to this issue. The prudent reader will understand that just because certain eyepieces did better than certain other eyepieces in this particular test, he or she may or may not get the same results by purchasing a different example of the same eyepiece.

(D) Magnification Differences.

Assuming that the published focal lengths are accurate for each eyepiece we tested, in the chosen test beds of 880mm focal length the eyepieces tested delivered between 110x and 126x. Several folks suggested that this magnification difference might skew the test results in favor of the shorter focal length eyepieces. After discussing different opinions on whether the near-1mm exit pupil generate by our chosen eyepiece focal length/telescope combination was close enough to the point where increased magnification really does not add increased resolution, we decided to proceed with the testing on the assumption that we were "close enough" to not have magnification differences skew the results.

You’ll see in our results below that a 7mm eyepiece won. That might tempt you to conclude that the 7mm eyepieces had an advantage over the 8mm eyepieces. Examining the data a bit more closely reveals that the semi-finalists included a 7mm pitted against an 8mm in each bracket. An 8mm, the second place eyepiece, was actually the only eyepiece in the test to receive perfect "5" scores from both observers in its semi-final round. Given the equal representation of 7mm and 8mm eyepieces in both the semi-finals and finals, we don’t think that increased magnification was the deciding factor in crowning or champion.

IV. The Groups.

With the caveats regarding weaknesses in the testing methods out of the way, let’s take a look at the eyepieces.

(A) Group A.

Here is a group shot of the Group A eyepieces.



From left to right: 7mm Pentax XW, 7mm Pentax SMC Orthoscopic, 7.5mm Orion (Vixen) LV, 7mm Takahashi MC Orthoscopic, 7mm Meade Research Grade Orthoscopic.

(B) Group B.

Here is Group B in all of its glory.



From left to right: 8mm Brandon, 7mm Baader Genuine Orthoscopic, 7mm University HD Orthoscopic, 7.4mm Meade Research Grade Wide Angle, 7.5mm Takahashi LE.

© Group C.

Here is the Group C photo.



From left to right: 7mm TMB Supermonocentric, 7.7mm Apogee Super Abbe Orthoscopic, 7mm Televue Nagler Type 6, 8mm Televue Plossl, 7mm University Optics Orthoscopic.

(D) Group D.

The members of Group D.



From left to right: 8mm Orion (Vixen) LVW, 8mm Baader Hyperion, 7.5mm Celestron Ultima, 8mm Edmund RKE, 8mm TMB Planetary.

V. Cry "Havoc" and Let Slip the Dogs of War – Battle is Joined!

With the pleasantries exchanged the quest for the title – 2009 Eyepiece resolution™ World Cup Champion – began in earnest. Testing commenced at approximately 8:20pm PST. Temperature at the beginning of the testing was around 45 degrees F with no wind and absolutely transparent skies. Humidity was low for the site and remained so throughout the testing. Proctor Jeff Cooke selected the Group A box as the first to be tested. Here’s how it went down.

(A) Group A Scores.

Eyepiece (Group-Number-Name)

cuzimthedad

jrbarnett

MakFun

A-1 7mm Pentax XW

4

3

3

A-2 7mm Pentax SMC Orthoscopic

3

4

3

A-3 7.5mm Orion (Vixen) LV

4

1


A-4 7mm Takahashi MC Orhoscopic

3

3


A-5 7mm Meade RG Orthoscopic

3

4

3


Group A was the toughest to score. After Dan and I completed our observations the group faced a 3-way tie. The 7mm Pentax XW, Pentax 7mm SMC Orthoscopic and surprisingly (to me at least) 7mm Meade Research Grade Orthoscopic all received a cumulative score of 7. Per our tie-breaking protocol, proctor Jeff Cooke was to observe the Trapezium with the tied eyepieces and score his observations using the same scoring system employed by the observers. After Jeff’s observations the 3-way tie remained. Per our tie-breaking protocol we resorted to random selection from among the tied eyepieces. The names of each eyepiece were written on a s**** of paper and the s****s were placed in a hat and agitated. Proctor Jeff then selected the Group A winner – the 7mm Meade Research Grade Orthoscopic.



At this point the three of us were very concerned that we might not be able to achieve definitive winners in any of the groups. I personally was a little sad to see the two Pentax eyepieces eliminated in this manner. Nonetheless, we proceeded with the contest. Jeff selected the box for Group B as our second set to be tested.

(B) Group B Scores.

Eyepiece (Group-Number-Name)

cuzimthedad

jrbarnett

MakFun

B-1 8mm Brandon

4

5

2

B-2 7mm Baader Genuine Orthoscopic

4

1


B-3 7mm University HD Orhoscopic

5

4

1

B-4 7.4mm Meade RG Wide Angle

4

5

0

B-5 7.5mm Takahashi LE

2

3



If the 3-way tie in Group A left us a little uneasy about the testing format, the 3-way tie in Group B was a downright confidence-shaking. Unlike Group A, however, Group B had a definitive winner selected not randomly but by observation scores. After Dan and I had scored the group, three eyepieces remained tied – the 8mm Brandon, 7mm University HD Orthoscopic and (surprisingly to me) the 7.4mm Meade Research Grade Wide Angle. Jeff’s tie breaking observations established the 8mm Brandon as the winner by one point over the 7mm University HD Orthoscopic and by two points over the 7mm Meade Research Grade Wide Angle.



The selection of a group winner based on scored observation and the elevation of an 8mm eyepiece over 7mm and 7.4mm eyepieces restored our confidence that our choice of eyepieces and target would indeed produce some useful results. Next proctor Jeff selected the Group C box for evaluation.

© Group C Scores.

Eyepiece (Group-Number-Name)

cuzimthedad

jrbarnett

MakFun

C-1 7mm TMB Supermono

5

4


C-2 7.7mm Apogee Super Abbe Orthoscopic

1

4


C-3 7mm Televue Nagler T6

4

4


C-4 8mm Televue Plossl

5

3


C-5 7mm University Orthoscopic

2

4



Unlike the prior groups, Group C produced a clear winner after Dan and I had completed our observations. The 7mm TMB Supermonocentric emerged as the favorite besting the cumulative scores of both Televues (the 7mm Nagler Type 6 and the 8mm Plossl) by one point.



This was the way it was supposed to work. With Group C tidily finished, Jeff proceeded to the final group, Group D.

(D) Group D Scores.

Eyepiece (Group-Number-Name)

cuzimthedad

jrbarnett

MakFun

D-1 8mm Orion (Vixen) LVW

4

3


D-2 8mm Baader Hyperion

2

1


D-3 7.5mm Celestron Ultima

1

1


D-4 8mm Edmund RKE

4

1


D-5 8mm TMB Planetary

2

2



It was with great joy that a clear winner emerged from Group D. The 8mm Orion (Vixen) LVW mopped up the group scoring with a cumulative score of 7 giving it a two point margin over the second place eyepiece, the 8mm Edmund RKE. Quite a feat given that the LVW has 8 elements in 5 groups versus the RKE’s scant 3 elements.



It’s also worth noting that this group included the three lowest scoring eyepieces in the contest, the 8mm TMB Planetary (4 points), 8mm Baader Hyperion (3 points) and 7.5mm Celestron Ultima (2 points).

(G) Semi-Finals.

With winners identified for each of the groups we proceeded to the semi-final round. First up was the winner of Group A, the 7mm Meade Research Grade Orthoscopic, versus the winner of Group D, the 8mm Orion (Vixen) LVW.

(i) Winner of Group A vs. Winner of Group D.

Eyepiece (Group-Number-Name)

cuzimthedad

jrbarnett

MakFun

Winner A 7mm Meade RG Orthoscopic

4

5

3

Winner D 8mm Orion (Vixen) LVW

5

4

1


The improvement in seeing by this time is very apparent from the scores. In head-to-head competition the Group A and Group D champions emerged tied with an impressive cumulative score of 9 each, tying the highest scores we’d seen thus far in the testing, and better than the scores received by these eyepieces in group competition. In a stunner, the tie was broken by our proctor, Jeff, who gave the 7mm Meade Research Grade Orthoscopic a 2-point margin over the runner up 8mm Orion (Vixen) LVW.

(ii) Winner of Group B vs. Winner of Group C.

Eyepiece (Group-Number-Name)

cuzimthedad

jrbarnett

MakFun

Winner B 8mm Brandon

5

5


Winner C 7mm TMB Sunpermono

4

5



In another stunner, Group B winner, 8mm Brandon upset my favorite, the Group C winner, 7mm TMB Supermonocentric, receiving the only perfect "10" score in the entire contest. Yes, the 8mm Brandon showed all 6 stars A through F constantly for two different observers. Quite an impressive feat.

(H) Finals – an Unlikely Winner Emerges.

Eyepiece (Group-Number-Name)

cuzimthedad

jrbarnett

MakFun

Winner AvD 7mm Meade RG Orthoscopic

4

5


Winner BvC 8mm Brandon

4

4



With the 8mm Brandon scoring a perfect "10" in its semi-final round and besting the 7mm TMB Supermonocentric to get to the finals, and the other finalist, the 7mm Meade Research Grade Orthoscopic, being of advanced age (25+ years old) and long out of production, I figured the Brandon was a shoe-in for the title.

Alas, no. In head-to-head, no-holds-barred single combat, a victor rose above the others. Please congratulate the 2009 Eyepiece resolution™ World Cup champion, the 7mm Meade Research Grade Orthoscopic!




VI. Thank Yous, Epilogue and Aftermath.

Before we indulge in a little post-mortem speculation, we would like to extend our thanks to those CNers who graciously lent us eyepieces for the testing. CNer Downward Bound provided the 7mm Pentax XW, which finished in Group A tied with the ultimate winner, and the 7mm TMB Supermonocentric that dominated Group C as its clear winner. CNer SteveC provided both the 7mm Baader Genuine Orthoscopic and 7mm University HD Orthoscopic in Group B. The latter was a close runner up to the second-place-over-all and only perfect score recipient, 8mm Brandon. In appreciation for their generosity O.F.L.I. had elected to send each of them a newly designed, just-released O.F.L.I. logo T-shirt. Thanks you!

You have the raw scores. You have our winner. But you also probably have more questions than answers. Here are a few of the questions that occurred to us: "What if either of the Pentax eyepieces eliminated randomly in Group A had made it to the semi-finals?" "Why did both Masuyama clones, the 7.5mm Takahashi LE and the 7.5mm Celestron Ultima fare relatively poorly?" "Was it seeing that caused eyepieces to score differently at different times in the competition?" For example, the 8mm Brandon received a 10 in its semi-final victory, yet ten minutes later it scored an 8 losing to the ultimate winner by a point. "What happened with the University HD Orthoscopic and Baader Genuine Orthoscopic twins?" These two are essentially identical save for the coatings, and the Baader coatings are generally regarded as being superior, but in our test the University HD Orthoscopic scored higher. Best of all…"Should anyone make an eyepiece purchasing decision based on these results?"

Though star count was our only criteria for differentiating eyepieces in this test, the raw data doesn’t convey the whole story. It gives the "what" was seen but not the "how" the view was rendered. The viewing experience through each of the various eyepieces was startlingly different. Certain eyepieces were obviously brighter than others. Apparent fields of view were all over the place. I found the 7mm Pentax XW, 8mm Orion (Vixen) LVW, 8mm TMB Planetary and 8mm Baader Hyperion, in particular, to deliver very comfortable aesthetically pleasing views of the multiple star system and nebulosity. Ironically, I also found the narrow 30 degree AFOV of the 7mm TMB Supermonocentric to deliver aesthetically compared to the 40 to 50 degree AFOV eyepieces in the test. The Supermono presented the most clinical and least distracting view in the test. If there was a scientist’s eyepiece in the batch, this was it. Though neither of them won their group, the two Televues, the 7mm Nagler Type 6 and 8mm Plossl, were solid performers. The Nagler’s consistent "4" score from both observers would have been good enough to have won were it in another group. I’ve often been a Televue Plossl advocate. The 8mm’s cumulative "8" score was likewise among the best cumulative scores in the test. The fact that it was one of the few eyepieces in our test to receive a "5" score from Dan is consistent with my past experience with the eyepiece. Ironically I gave it a good-but-not-great "3".

I suppose the best way to sum things up is to say that few of the eyepieces in the test are likely to disappoint owners. On the other hand, if pulling in challenging details is on the observing menu, the eyepieces that received high cumulative scores in our test are unquestionably up to the task. Put another way, if a friend asked our advice on purchasing an eyepiece in the 7mm to 8mm range, we would recommend any of the high cumulative scorers in this test without hesitation or reservation.

Here are the eyepieces that received a cumulative score of "7" or better in our test:

7mm Pentax XW
7mm Pentax SMC Orthoscopic
7mm Meade Research Grade Orthoscopic
8mm Brandon
7mm University HD Orthoscopic
7.4mm Meade Research Grade Wide Angle
7mm TMB Supermonocentric
7mm Televue Nagler Type 6
8mm Televue Plossl
8mm Orion (Vixen) LVW

And that’s the way it was on the Farm.

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