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Posts Made By: William Paolini

September 15, 2006 09:24 PM Forum: Eyepieces

Final Release for EP Eval Form

Posted By William Paolini

The attached images are the final incarnation of the form modified based on my 1st use of it for the 5mm eyepiece comparison.

Major changes include limiting the afov areas to 3 regions instead of 4 because 4 was too difficult to judge accurately. Other change was in scoring and instead of just having a composite score, layed out scores for each major area as different things are more or less important for different people...so makes it a little fairer or evaluation-friendly. Narrative is the same pretty much and included in main form although not shown in the attached image to keep under the 500K file size restriction on the forum.

If anyone wants a copy emailed to them, shoot me a note with your address.

Thx,
-Bill

=====NARRATIVE======

5mm TeleVue Radian (1st Place for Planets, Globulars, Nebula):
Clearly a well corrected eyepiece! Star images remained intact to almost the extreme edge. Star point size was only average compared to the rest. On Jupiter it suffered from some internal reflections and many eyeball glint reflections, to the point of being not annoying but very noticeable. Eye positioning was also sensitive, giving partial blackout if not correct. This again was not annoying, except on the Moon where it happened more than I liked. It also suffered from some fairly significant CA off-axis. This showed as very noticeable on Jupiter and 1st magnitude stars. On 2nd magnitude stars it became much less detectable. I did not see any CA on stars dimmer than 2nd Magnitude -- for normal viewing of clusters CA was not apparent. On Jupiter is also showed quite a bit of CA, but again, the extra detail it showed on the surface negated that problem. Overall stars also had a warmish or yellowish cast. This was especially noticeable when switching to any of the other eyepieces in the comparison. Therefore, for the majority of celestial objects, the CA, although sometimes significant, was not much of an issue in practical use. However, despite all these issues, and while the Radian was not the sharpest eyepiece in the bunch, it clearly put up the most detailed on-axis view of Jupiter. So of the bunch, it came in #1 for Planets showing much more details in the bands and festoons of Jupiter, so much so that it diverted ones attention from the CA on Jupiter’s fringe. So as far as planetary performance is concerned, of the bunch I was getting the best resolution of fine detail on Jupiter with the Radian 5mm – however, the Siebert 5.9mm Star Splitter was only ever so slightly behind showing detail and further behind showing atmospheric shadings due to its neutral coatings. The others fell well behind, even the SuperMono which for me was performing only a very slight tad better than the UO HD.

On Globulars the Radian also came in #1 for both an expected and unexpected reason. As expected, its wider AFOV at the 240x magnification in my scope, and therefore wider TFOV, put the Globulars (M13 for this test), and nebula (M57 for this test) in more context with the surrounding star field making them more pleasing and interesting to observe. Unexpected was that it’s average star spot size seemed to work as an advantage for Globulars , accentuating the larger brighter stars while still showing finer points for the dim stars. The effect overall was that it gave the globular a more 3 dimensional look. So the Radian was #1 for high power views of nebula, Globulars and planets. It’s performance on the Moon and general star fields was not as well as some of the contenders. Star colors also did not seem to translate as well as they did in the other eyepieces. White stars had a bit of a warmish tint, red stars did not come across as red, and yellow stars seemed overly so. So for color contrast doubles or multi-color stars in Open Clusters, the Radian was not the best choice; it does however have a definite high-power niche excelling on Planets, Globulars, and Nebula.

5mm TMB SuperMono (1st Place for Lunar Detail):
The SuperMono’s reputation precedes itself as the ultimate for resolution and contrast. I had never used one before so had many great expectations. Unfortunately, for the majority of objects observed, it did not perform well in my fast Dobsonian. On Jupiter it showed minor CA even on-axis. The biggest issue however, was the outer 50% of the AFOV was very soft, too soft for serious observing and evidenced as bloat on star images. And while the central region was sharp, this was small given its total AFOV of only 30 degrees. On stars it was also a less well corrected lens and with my fast f-ratio mirror coma appeared starting at the 50% mark from center and got quite moderate the last 25%. So while this eyepiece may be a great performer in optical designs without coma (APOs, Achros, SCTs, etc.) it is apparently not a good choice for fast Newtonians.

On Jupiter, it’s performance fell between the UO HD and the Radian. As a high power planetary eyepiece for a Mid-sized aperture Dobsonian I would therefore not recommend it. The UO HD’s on-axis performance was very close, its off-axis performance was much better, had a wider AFOV, and only half the street price – overall the better choice. The small AFOV was also a hindrance for performance on Globulars and nebula because of the resulting very limited TFOV just did not give enough context. True it did have the darkest background FOV, and if it did have better light transmission it was not apparent on stars but only showed up in nebula where the Ring Nebula (M57) appeared just slightly brighter compared to the others eyepieces. While its performance seemed to be lacking on most objects viewed, I found its niche on the Moon. Lunar observing was just spectacular, showing incredibly more detail on-axis than any of the others. It was also very apparent that it showed more contrast as what appeared as delicate shading differences on the lunar surface in the other eyepieces popped out as significantly dark shadings through the SuperMono. While the restrictive AFOV made re-navigating back to a spot on the Moon more difficult, and the 50% off-axis image was much too soft, the reward of the extra fine detail and high contrast shades on-axis made up for that several fold! Definitely a #1 Lunar performer in Newtonians. I spent quite a bit of time examining the very rich fine details in and around Crater Clerke (Longitude: 29.8° East; Latitude: 21.7° North).

5mm University Optics HD ABBE Orthoscopic (1st Place for Stellar Color Rendition):
While the UO HD ABBE did not excel as #1 on any celestial object, it came in as a good to very good performer on everything! If I had to characterize this eyepiece, I’d say it is a generalist and a very good one, worth every penny if not more so than its street price. It’s lunar imagery was more detailed than the Radian’s and it’s star point size seemed to be a tad smaller. Background darkness was good, but still exceeded by both the Radian and the SuperMono. A special characteristic unique to this eyepiece over the others though, is that it seemed to put up a slightly brighter star and had the most neutral effect relative to stellar coloring – red stars appeared redder, whites whiter, blues bluer, etc. When circumstances are such that one needs to focus critically on stellar colors, this is where I’d reach – so its niche is very specialized as #1 for Stellar Coloring.

5.9mm Siebert Star Splitter (1st Place for Open Clusters and Double Stars):
Like the UO HD, the Siebert Star Splitter also performed admirably across the board on all objects. However, it edges out the UO HD often placing in the #2 spot behind those eyepieces that took #1 positions on particular classes of celestial object. For lunar detail it was a #2 behind the SuperMono, and it was only ever so slightly #2 behind the Radian on Jupiter putting up a good fight against both. The primary edge the Radian had on Jupiter was probably due to its warm coatings. While the resolution of the Star Splitter shows excellent details, its cooler/neutral coatings present more of a washed-out view of Jupiter’s clouds compared to the Radian. On Globulars the Star Splitter had the same advantage as the Radian with the larger AFOV, but its extremely small star point size did not work as an advantage for Globulars under these observing conditions. However, for Open Clusters and splitting doubles it did excel over the others, coming in as #1, but not by what I would characterize as an order of magnitude. While it’s focal length was slightly longer than the others, and many will say this could be a factor for any noted differences, I would tend to disagree that it was a significant factor. I did not have a 5mm Star Splitter and wondered myself how much of an issue this might be, so I did a quick compare on a few objects using a 5mm UO HD and a 6mm UO HD to see if this 1mm (240x vs 200x) made any difference in details. Flipping between the 5mm and 6mm UO HDs showed now noticeable difference in image details or quality on-axis. Because of that, I tend to believe that the performance of the 5.9mm Star Splitter is valid compared to the 5.0mm test companions and would hold true if the Star Splitter were also 5.0mm. Finally, in addition to being a better generalist than the UO HD, and almost equaling the Radian on Jupiter, the Star Splitter does have a very specialized niche where it performs #1, this was in star point size. The Star Splitter easily produced the finest star points compared to the others in my fast Dobsonian. An excellent eyepiece for splitting the most difficult of doubles, and #2 in most other categories compared to its competition.

September 18, 2006 07:20 AM Forum: Eyepieces

When the Eyepiece Finally Dies...

Posted By William Paolini

OK. Regardless of what any of us may "desire," the writing is on the wall and one day the eyepiece will be something of the past era. Granted we may be several decades away from that reality, but it is coming.

Let's assume it is here and our scope are standard with electronic observing gadgets. So if you were to keep JUST ONE of your personal eyepieces on display as novel artifacts of a time gone by, what would they be?

Me...If I hadn't sold it it would have been my 1st premium eyepiece that I purchased when they 1st hit the market in the 80's, the nice compact powerful newcomer, the 4.8mm Nagler Smoothside. Mostly not because of it's performance, but because of my history with it and the industry's.

Otherwise, from, my current inventory I'd keep the 24mm TV Wide Field for the same reasons as I got it with the 4.8 I let go.

September 18, 2006 07:31 PM Forum: Eyepieces

TMB 40mm Paragon

Posted By William Paolini

Well, I finally got a chance to do some real observing with my new TMB Paragon.

WoW. Performs wonderfully! Easily equals the light throughput of the Siebert 36mm Observatory and beats it hands down in edge performance in my 10" f4.7 Dob. There is a very minute amount of pincushion, but you really have to look for it in daytime observing, and only at the extreme edge. Central 75-80% afov is sharp, then at 20-25% from edge some barely detectable CA happens but only on Mag 1 to 1.5 stars. Also at 20-25% from edge start getting some field curvature that becomes noticable or moderate at last 10% (but on a re-focus even the last 10% to the edge the star stayed sharp).

Absolutely no blackout/kidney beaning and zero secondary shadow and no ghosts of any kind on Mag 1 stars.

Field stop tac sharp and very good contrast. Advertized as 69deg AFOV and looks every bit of it. AFOV of Nagler looked larger or course but only by 10-15 deg max. Interestingly, the Siebert AFOV did not look as big and advertised as 70deg afov but appeared smaller, perhaps perhaps 8-10 deg less in comparison to Paragon. Could easily get 4 widths of the Perseus Double Cluster in my TFOV, so that should be 2+ degrees as predicted.

Fit and finish excellent, light but still heavy enough to feel solid and well built.

This is a real keeper and quite a bargain price at $250 new. Based on the performance of this, will definitely want to get the 16mm and 24mm when they come out.

-Bill

September 24, 2006 09:26 PM Forum: Eyepieces

Reducers

Posted By William Paolini

Does anyone have thoughts (i.e. recommendations) on whos reducers they feel are execptional optically?

I'm only interested in the 1.25" adapter type that screw into bottom of the eyepiece. Or if there are any that are like a barlow where you just pop the eyepiece into the assembly. I use a Newt exclusively.

I have an ancient Celestron one from back in the 80's that does ok. Anyway, please let me know if you have any recommendations.

btw - to anticipate an oncoming question of why in the world would I use these if I have a fast Newt? ...because I enjoy finding a single eyepiece that performs outstandingly, then just barlow it up or down for my EFL needs in viewing.

October 4, 2006 08:59 AM Forum: Eyepieces

Best Current Production High Power EP

Posted By William Paolini

Would like to know everyone's recommendation for what they have experience with and consider to be the absolute best performing high power eyepiece (10mm or shorter fl). Price is to be no object in the equation and the EP must still be in production. If you want to also recommend an out-of-production unit, that's fine but please don't forget your in-production selection. If you can give a short list of what it's better than, that would be great too smile

Would potentially like to add one very very best available EP to the stall. Planets and Lunar is where most of it's time will be spent.

Thx!

November 2, 2006 07:36 AM Forum: Eyepieces

More Respect for the Ortho Design

Posted By William Paolini

Regarding the venerable Ortho eyepiece design and newer more complex designs, I agree and observe what has been expressed in recent forum threads.

However, sometimes it does just amaze me in unexpected places. Last evening the Moon was presenting a nice opportunity. Occasionally I throw an eyepiece in that frames the entire orb to get perspective and see what's showing of interest to zero in on. I generally use either my 25mm OU Super Erfle, or 12mmT4 Nagler, or 24mm TV Wide Field for this task. But last evening I decided to use a little used EP, my 18mm Pentax SMC Ortho. All I can say is OMG!!! The entire surface was just incredibly crisp from limb to limb and it felt like each mountain was sticking up for the picking on a prickly orb! Anyway, it was a "step back" experience.

So I guess, even though it's an old design, with a small afov, it still apparently has some unbeaten "records" to its credit smile So anyway, it's moved up to my #1 place for entire Moon observing, leaving the others in the celestial dust.

So...while I have a host of complex wide fields in the case, the Orthos will always have a permanent home.

November 20, 2006 09:33 AM Forum: Eyepieces

Measuring EP Focal Length

Posted By William Paolini

Is it possible to measure the focal length of an eyepiece to determine if it is what the manufacturer claims??

I understand it's not really possible for those eyepieces with integrated barlows. But for others, no measurement seems to be any where near close when I measure where it comes to focus with a light source.

For instance...I have a 60mm Kellner. But even with this, if I move a paper in it to find where it brings an image into focus, it is way different from 60mm distant from either the lower or upper element. Flipping it and measuring where image focuses in reverse also produces nothing close to 60mm.

Any suggestions?

November 21, 2006 08:40 AM Forum: Equipment Talk

Recommend a 2" Diagonal

Posted By William Paolini

Can anyone recommend a good 2" diagonal that won't break the bank. Would prefer to keep it $100 +/- (I like the minus better).

Also give me your vote for a 1.25" model as well. I only have 1 2" EP (40mm Paragon) so could live straight for that as I don't do scanning all that often...maybe 2-3 times a year! So will be in 1.25" land vast majority of time.

Thx

November 27, 2006 10:14 AM Forum: Mounts

Recommend an Alt-Az

Posted By William Paolini

OK. I have an 80mm F/11 OTA I need to mount. I will be working at the power limits most of the time (170x-250x) so stability a must. Also, like everyone, don't want to break the bank either.

I was looking at the TeleVue/Vixen porta mount, also the Universal brand seemed interesting, and understand WO has an offering with their EZ Touch. So all seem to be in the $300-$500 range.

Anyone have any experience? Looking for most stable with shortest dampening time. Encoder capability not wanted.

Thx.
-Bill

December 6, 2006 12:31 PM Forum: Eyepieces

UO 32mm 1.25" Konig

Posted By William Paolini

Does anyone know when these (UO 32mm 1.25" Konig) were discontinued?

FYI - I just picked one up used and it is an unbelievable performer. In f/4.7 scope only outer 25% or less was soft on star fields. In f/11 scope was sharp until last 5% or less! AFOV apprears wide, much wider than a Plossl. Anyway, a great EP.