Brooklyn
scholastic sledgehammer
Reged: 07/24/08
Posts: 870
Loc: Central New Jersey
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So I have a 5mm and 8mm baader hyperion eyepiece from optcorp on the way to my house.
The 8mm will give me 250x, while the 5mm offering 400x (which ends up being my max at 50x per inch of aperture).
I did some extensive research on these eyepieces and it turns out that you can change the focal length in different ways.
http://www.alpineastro.com/Hyperion-Eyepieces_com/Images_and_Docs/HyperionandZoomInstructions-Version2.pdf
By taking apart the baader hyperion eyepieces you can change the focal length and stop field in small or larger quantity depending on what you do.
There is a 14mm FTR and 28mm FTR which can be used singularly or together. It will give even smaller focal lengths of a given eyepiece.
For example I can take a 8mm baader hyperion and...
with 14mm FTR: 6.0mm
with 28mm FTR: 5.0mm
using both FTR together: 4.3mm
All this info and more can be seen on the chart from the link above.
Do you think I made a mistake getting the 8mm AND 5mm?
I ask this because I could have turned my 8mm into a 6, 5mm or even 4.3 using these two modification inserts.
Has anyone here personally had any experience with these eyepieces and using the optional threads to mod them into different lengths?
Is it worth modding the eyepiece? or does the performance suffer at all?
I know some people have bought the ENTIRE baader hyperion set which leads me to believe that modding these eyepieces isn't such a good idea?
Anyone with knowledge of this subject, educate us!!
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Meade 8.25"(209.55mm) LX-90 EMC (SCT)
Albert Einstein =>
“Intellectual growth should commence at birth and cease only at death.”
“If you can't explain it simply, you don't understand it well enough.”
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Brooklyn
scholastic sledgehammer
Reged: 07/24/08
Posts: 870
Loc: Central New Jersey
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http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/1504610/page/0/view/collapsed/sb/5/o/all/fpart/1/vc/1
Here is an old thread from 2007 that i pulled up.
I notice there are some bad drawbacks to actually using these extention rings...
"
When do you use your extension rings? Do you add/change them while observing, or do you adjust your EP's before hand based on what you want to observe? Just curious.
Tom
They _can_ be changed in the field. It's pretty much like putting a filter on. That said, it has to be a clean environment since cleaning the internal two lenses is going to be very hard. I have done it in the field to see how it works since I'm lens poor. It's also not very dirty/dusty where I observe. I own a 13mm and I plan to keep the either the 28mm or 14mm installed to give me a 11 or 9mm eyepiece. Not sure which yet.
I have a 17mm and 13mm. The next time I'm out I'm going to add in a tuning ring to convert the 17mm down to 13mm and I will compare the two in the field.
Do be warned the eyerelief seems to reduce when you add in the fine tuning rings. The 17mm with the 28+14mm seems to have about 10 maybe 12mm of eye relief. I think. " -post by boren.
So this post stated that using these Fine tuning rings (14 and 28) cause the 20mm of eye relief to drop down to 10-12mm? how is this possible? How can decreasing the focal length have such an impact on eye relief?
The eye relief issue is the only negative aspect of using the FTRs.
Anyone have any experience or opinions on this?
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Meade 8.25"(209.55mm) LX-90 EMC (SCT)
Albert Einstein =>
“Intellectual growth should commence at birth and cease only at death.”
“If you can't explain it simply, you don't understand it well enough.”
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Wobrak
super member
Reged: 04/18/08
Posts: 186
Loc: SC, USA
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I use to own 17mm Hyperion and 14mm & 28mm FTR. I noticed two things, first as stated above the eye relief was shortened and the FOV was smaller. The 14mm FTR wasn't too bad, IMO it made the eye relief better and the FOV only slightly smaller. The 28mm FTR made the 17mm into a straw. The eye relief wasn't too bad but the FOV suffered. I never tried combining the 14mm & 28mm FTR on the same EP.
IMO, the Fine Tuning Rings are not really worth it. Maybe initially if you only buy 1 or 2 EP's they may fill a gap. But as time goes and you purchase more EP's the FTR will end in a box unused.
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Karl
Zhumell 20x80 Binos
Zhumell 10" Dob
WO 28mm UWAN
TV 13mm Ethos
TV 8mm Ethos
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Lawrence Sayre
Post Laureate
Reged: 10/16/04
Posts: 3611
Loc: N.E. Ohio
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Quote:
I use to own 17mm Hyperion and 14mm & 28mm FTR. I noticed two things, first as stated above the eye relief was shortened and the FOV was smaller.
The FOV (as in TFOV) for any eyepiece series of a given AFOV will diminish as the magnification level increases. This is not a fault of your Barlow extension tubes. The same would be observed for a stand alone eyepiece with greater magnification (shorter focal length).
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My philosophy, in essence, is the concept of man as a moral being, with his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute.
Ayn Rand (in the appendix to 'Atlas Shrugged')
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DSalters
sage
Reged: 03/03/07
Posts: 434
Loc: High Ridge, MO (St. Louis)
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I currently own the 17, 13, and 8mm Hyperions. Just as the table shows, the FOV does get larger. I have not used my 14mm FTR much YET with these EPs but have been pleased so far with everything I have seen. Personally, I will not be buying a 28mm ring and will stack two 14mm rings when necessary. The reason is, 17 and 13mms are too close for me. I will permanently make the 13mm an 11mm.
The other ring will be for the 8mm. I can turn it into a 6mm with one ring, or I can pull off the other ring from my 13mm and double up to take the 8 down to a 5mm. Any higher magnification can be done with my 4mm BO/TMB.
This seems to cover all of the necessary magnificaitons I would need on most nights with only three EPs.
Again, though, I have seen no negative views with these in use, but with more use, I may find aspects I do not like. For now though, I'm quite pleased.
Hope all of my EP and FTR switching around, etc. wasn't too confusing! 
Daniel
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6" f/8 Bushnell Voyager Dob. Rebuild
10" f/5 Highe Dob. variant
(UNDER CONSTRUCTION: 5" f/5, 8" f/6, 13" f/4.6)
Baader Hyperions--Primary Eyepieces
"The sun has one kind of splendor, the moon another and the stars another; and star differs from star in splendor." -1 Corinthians 15:41
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Brooklyn
scholastic sledgehammer
Reged: 07/24/08
Posts: 870
Loc: Central New Jersey
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Good info here.
There must be a reason so many people buy the entire baader hyperion set.
If one was on a budget and looking to stretch their wallet, it may be wiser to get only 3 different eyepieces with the 2 FTR pieces.
So far from what I know, the only thing you lose when you mod the baaders is the 20mm of eye relief.
Ive seen several people state that they went from 20mm (the standard on all but the 24mm models) of eye relief to a shocking 8-12mm.
This somewhat destroys the purpose of the eyepiece as it is supposed to be a small focal length but comfortable eyepiece to use, not having to use barlows to extend the eye relief.
For example, since I took a 8mm and 5mm, both will have 20mm of eye relief. From what i understand if i use the 27 fine tuning ring on the 8mm, it will turn into a 5mm but the eye relief will be somewhere between 8-10mm, which is like looking through a straw.
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Meade 8.25"(209.55mm) LX-90 EMC (SCT)
Albert Einstein =>
“Intellectual growth should commence at birth and cease only at death.”
“If you can't explain it simply, you don't understand it well enough.”
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Lawrence Sayre
Post Laureate
Reged: 10/16/04
Posts: 3611
Loc: N.E. Ohio
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Eye relief and looking through a straw are not related concepts. The 16 mm Nagler T5 has only ~10 mm of eye relief, yet it has an 82 degree AFOV. A 16 mm Abbe would have 12.8 mm eye relief and an AFOV of only 40 degrees. Only the latter approaches looking through a straw, but in reality is nowhere near that bad. Either way, in this case the more straw like eyepiece has the greater eye relief.
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My philosophy, in essence, is the concept of man as a moral being, with his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute.
Ayn Rand (in the appendix to 'Atlas Shrugged')
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Brooklyn
scholastic sledgehammer
Reged: 07/24/08
Posts: 870
Loc: Central New Jersey
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sorry about that lawrence S., i really should have made it a clearer expression.
I meant to respond to the quote:
"The 28mm FTR made the 17mm into a straw. The eye relief wasn't too bad but the FOV suffered."
But yea you're dead on, straw eyepieces come from smaller fov.
Heres a new question which has arisen from the previous...
People have said that their eye relief and FOV suffers when using these FTRs to decrease the focal length.
If the FOV gets smaller why does the table (linked in original post) show that the field stops are actually larger for a 8mm modded into a 5mm, than a retail 5mm non modded?
Taken from the chart mentioned previously,
8mm = 10.7mm field stop, an 8mm w/ FTR modded into a 5mm has a 7.1mm field stop.
5mm = 6.5mm field stop
So.....5mm retail = 6.5mm field stop VS a 7.1mm field stop in the modded 8mm to 5mm.
Is the field stop directly related to FOV? if so wouldnt this mean that the modded 8mm has a bigger fov than a 5mm?
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Meade 8.25"(209.55mm) LX-90 EMC (SCT)
Albert Einstein =>
“Intellectual growth should commence at birth and cease only at death.”
“If you can't explain it simply, you don't understand it well enough.”
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Lawrence Sayre
Post Laureate
Reged: 10/16/04
Posts: 3611
Loc: N.E. Ohio
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The field stop is directly related to TFOV, and somewhat less directly related to AFOV. The "less related" part gets involved in rectilinear and angular magnification distortion issues which compound the AFOV issue. For Barlowed eyepieces it is quite tricky to "measure" the field stop. Therefore field stop figures for eyepieces with built in Barlows are more properly termed "calculated" than "measured".
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My philosophy, in essence, is the concept of man as a moral being, with his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute.
Ayn Rand (in the appendix to 'Atlas Shrugged')
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BillP
Carpal Tunnel
Reged: 11/26/06
Posts: 1986
Loc: Vienna, VA
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I have used the FTRs on the 13, 8, and 5mm Hyperions to make each of them 10mm, 6mm, and 4mm respectively and if the AFOV or eye relief changed, it was not readily obvious.
As far as adding the rings while in the field at night, I never had any problem...you just have to be careful to not drop anything while you have it apart of course (so a 3rd hand or a table top makes it a bit safer, but you can manage with just 2 hands and no place to put things down as well - the latter was the most often used method).
My only caution would be that if you plan to add both the 14 and 28 FTRs to say the 13mm or shorter FL Hyperions, then you will end up which quite a large EP! So if ergonomics are a consideration then something to think about....I doubt with both FTRs on that they will fit in the typical tray under the tripod as they will be a bit long.
Finally, I don't know about the longer FLs, but I felt that the 5mm Hyperion deteriorated some with the FTRs attached and off-axis CA was a bit more pronounced when the 5mm was pushed to 4mm. I don't recall this with the 13 or 8mm when the FTRs were attached.
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250mm f/4.7 Orion XT10i Dobsonian
127mm f/12 Orion Apex Mak
102mm f/8.0 Tak TSA Super-APO 
066mm f/5.9 WO ZenithStar SD APO
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Brooklyn
scholastic sledgehammer
Reged: 07/24/08
Posts: 870
Loc: Central New Jersey
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Hmm interesting info here BillP, I have been having quite a large number of members here advise me to NOT use the FTR rings and instead just buy more eyepieces.
At 120 dollars, you really cant say no. There are five people that i can think of off the top of my head who are very adamant about owning the entire baader hyperion set.
Lets not forget...baader planetarium and Zeiss are almost like brothers. They work together on many projects and the future of both companies seem intertwined with each other.
If you had to rely on any optical company in the world, who else can you trust more than Zeiss? Theyre the original, the best, the most trusted in the world.
With that said, at 120 US, the hyperions are really more quality than anyone should be getting for the price.
Add to this the fact that you can mod your eyepieces for a measily 12-13 dollars for each of the 2 FTRs, and its really understandable why people would rather just buy the whole set rather than frustrating themselves or possibly hurting the eyepieces by constantly taking them apart.
I am not the type who buys many eyepieces every year, not only because of financial restrictions but also since I think realistically there are only 2-5 eyepieces that a person would use at a given observing session, with those 5 being their best. All of the other eyepieces would from that point on just be unused gaining dust in some drawer or box stored away. Since telescopes are an instrument that can be used 10-30-even 40 maybe years since their purchase, I have the feeling that eyepieces should be picked out carefully otherwise the newer ones would just obsolete the older ones. Ethos anyone??
I got a 8mm and 5mm, and although i kind of thought the 5mm was a waste since the 8 can be made into a 5 anyways, I am getting the feeling that this route was the best one. 
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Meade 8.25"(209.55mm) LX-90 EMC (SCT)
Albert Einstein =>
“Intellectual growth should commence at birth and cease only at death.”
“If you can't explain it simply, you don't understand it well enough.”
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Lawrence Sayre
Post Laureate
Reged: 10/16/04
Posts: 3611
Loc: N.E. Ohio
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Hyperions are not related to Zeiss.
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My philosophy, in essence, is the concept of man as a moral being, with his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute.
Ayn Rand (in the appendix to 'Atlas Shrugged')
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NGC6144
member
Reged: 07/24/08
Posts: 47
Loc: Virginia Beach, VA
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but baader is. Hyperions are excellent.
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Orion Skyquest XT10i w/telrad
21mm Hyperion
8mm hyperion
Messier objects observed this year:65
caldwell objects observed this year:10
Herschel 400 objects this year: 9
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Brooklyn
scholastic sledgehammer
Reged: 07/24/08
Posts: 870
Loc: Central New Jersey
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baader and zeiss are basically brother or sister companies. Since they work so closely together, its no shock that baader planetarium products are such high quality.
I bet neither zeiss or baader predicted that the hyperions would be such a smash hit...ive never seen an eyepiece sold out this bad all over the world. Its been quite a long time since the hyperions were introduced and they are still sold out in most retailers, which is surprising as peak sales usually occur within 6 months of product introduction. Keeping inventory on this item seems to be a big challenge.
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Meade 8.25"(209.55mm) LX-90 EMC (SCT)
Albert Einstein =>
“Intellectual growth should commence at birth and cease only at death.”
“If you can't explain it simply, you don't understand it well enough.”
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Lawrence Sayre
Post Laureate
Reged: 10/16/04
Posts: 3611
Loc: N.E. Ohio
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Quote:
but baader is. Hyperions are excellent.
And the connection to Zeiss here is?
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My philosophy, in essence, is the concept of man as a moral being, with his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute.
Ayn Rand (in the appendix to 'Atlas Shrugged')
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Lawrence Sayre
Post Laureate
Reged: 10/16/04
Posts: 3611
Loc: N.E. Ohio
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Quote:
baader and zeiss are basically brother or sister companies. Since they work so closely together, its no shock that baader planetarium products are such high quality.
Aside from the Baader/Zeiss Barlow, what other products can you specifically reference to support this close association theory. Mere distribution (even if perhaps preferred) does not mean a sister relationship. And more to the point, distribution of one companies product lines does nothing to add credence or an air of quality to the distribution of another unrelated companies product lines.
If it did, then perhaps WalMart could state something to the effect that "Everything in our store is absolutely the very best in quality because we sell Canon cameras."
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My philosophy, in essence, is the concept of man as a moral being, with his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute.
Ayn Rand (in the appendix to 'Atlas Shrugged')
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BillP
Carpal Tunnel
Reged: 11/26/06
Posts: 1986
Loc: Vienna, VA
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Quote:
Hmm interesting info here BillP, I have been having quite a large number of members here advise me to NOT use the FTR rings and instead just buy more eyepieces. ...
I didn't mean to advocate one way or the other on this...just passing on my experiences using the FTRs. I myself had almost the entire set because as you say, relatively inexpensive. I had the 24, 17, 13, 8, and 5mm. I still used the FTRs though as for some scopes, the 4mm and 6mm focal lengths were just more appropriate. If you can afford a large set, then by all means. However, if you can't, particularly for the higher powers, for me it was just as easy to slip on a ring in the field as opposed to adding the 3.5mm for instance. I used the 13mm the most by far, so looking back would have probably been better to just get the 17mm with the FTRs to get me near there. However, after much time with them, more often that not I went observing with only the 24, 17, and 13mm and a Klee 2.8x barlow as they barlowed wonderfully. So after a time, the 8mm and 5mm were less and less used.
So really it all depends I think on your personal likes. If you don't mind altering their configuration and saving some bucks, then it's easy enough to do. Otherwise, considering you can pick them up used for $85-$90 each, getting a set of 5 or 6 is a real good deal also.
If you like to tinker....these are really fun eyepieces. So kind of neat to be able to transform a series into a whole new set of focal lengths. Then if you are more brave, they are quite easy to take apart and modify -- for instance when you remove the chrome barrel and the 2 large elements just above the chrome barrel (#3 in the photo), then 5mm Hyperion becomes approximately a 2" 26mm 80-ish deg eyepiece that is actually fairly well corrected and cleans up fairly nicely with a Paracorr. At times I keep the 5mm in this configuration for a few months, then put it all back together for 5mm mode again, then take it all apart again and put it back into its cannibalized 26mm configuration. Basically a fun eyepiece.
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250mm f/4.7 Orion XT10i Dobsonian
127mm f/12 Orion Apex Mak
102mm f/8.0 Tak TSA Super-APO
066mm f/5.9 WO ZenithStar SD APO
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Brooklyn
scholastic sledgehammer
Reged: 07/24/08
Posts: 870
Loc: Central New Jersey
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bill thanks so much for linking that picture, i have researched the hyperions to death but for some reason havent come across that particular shot of the ep dissasembled.
"Aside from the Baader/Zeiss Barlow, what other products can you specifically reference to support this close association theory. Mere distribution (even if perhaps preferred) does not mean a sister relationship. And more to the point, distribution of one companies product lines does nothing to add credence or an air of quality to the distribution of another unrelated companies product lines."
Lawrence ive got several reasons why I know zeiss and baader are intertwined companies.
But really the only way i know this is because their distributor in the usa mentioned that they are a "sister company", that they share resources and production facilities and techniques. I called to ask about any future versions of the hyperion coming out and also about the abbe2's.
http://www.alpineastro.com/Eyepieces_Accessories/Eyepieces_Accessories.htm
Take a look at the abbe 2 eyepiece set, which if im not mistaken, is the single BEST and most expensive eyepiece ortho set ever.
"Baader Planetarium has spent years working with Carl Zeiss to design and produce an eyepiece at the limits of modern optical design and fabrication technologies. The result is the Abbe-II."
here is an excerpt from the Abbe Zeiss Barlow, which is being sold ONLY with a set of abbe 2 eyepieces.
"Baader Planetarium and Alpine Astronomical are elated to now offer again the legendary Carl Zeiss Abbe-Barlow, in a new redesigned housing. Carl Zeiss has produced a new run of these barlows, specifically for Baader Planetarium. The lenses have been mounted in an all-new housing, which incorporates Baader's own Clicklock eyepiece clamp that attaches to the barlow housing via T-threads. The marriage of these two parts makes an even finer barlow than the 1995 original style."
Oh also, phantom does proprietary work for baader planetarium exclusively, but there is talk of them also working on some zeiss optics that will be released in the future.
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Meade 8.25"(209.55mm) LX-90 EMC (SCT)
Albert Einstein =>
“Intellectual growth should commence at birth and cease only at death.”
“If you can't explain it simply, you don't understand it well enough.”
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BillP
Carpal Tunnel
Reged: 11/26/06
Posts: 1986
Loc: Vienna, VA
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Quote:
bill thanks so much for linking that picture, i have researched the hyperions to death but for some reason havent come across that particular shot of the ep dissasembled.
...
You will not find that pic on the Internet since it is my personal 5mm which I have disassembled.
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250mm f/4.7 Orion XT10i Dobsonian
127mm f/12 Orion Apex Mak
102mm f/8.0 Tak TSA Super-APO
066mm f/5.9 WO ZenithStar SD APO
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Phillip Creed
Idiot Seeking Village
Reged: 07/25/06
Posts: 1006
Loc: NE Ohio
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Bill,
Does the "Frankensteinian" 26mm EP you get from removing elements from the 5mm have about the same edge correction as a regular Hyperion?
Clear Skies,
Phil
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"Why suffer from insanity when you can revel in it?"
Wilderness Center Astronomy Club member since 1995
ICQ Comet Observer Code: CRE01
*****
16" f/4.5 Truss Dobsonian
Orion 120mm ST Refractor
23mm Axiom LX
13mm Ethos (FOR SALE!)
13mm Nagler Type 6
9mm Nagler Type 6
1.75X Siebert Barlow
*****
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BillP
Carpal Tunnel
Reged: 11/26/06
Posts: 1986
Loc: Vienna, VA
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No. It's better corrected off-axis without those elements. Quite unexpected. So if all you do is remove the Smyth group in the chrome barrel the edge is quite horrible with the 5mm. Much better when you remove the others as well so you are only left with a 4-element design. Throughput is noticably better as well given 2 doublets just got removed -- not that it was bad to begin with. Again, it's no Nagler (although I lovingly call it my 26H5), but much better correction than simply removing the Smyths IMO.
FYI, I've done this also with the 17mm, and I recall it is not bad either. However, unlike the 5mm, for some reason the elements in the upper housing iof the 17mm are not held in by a retaining ring but instead using the barrel housing to do this. So once you break the light glue seal they use to unscrew the 2" housing (at the joint where the rubber grip is), the elements will fall to the floor if you are not careful with the 17mm. I guess you can figure how I know that huh 
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250mm f/4.7 Orion XT10i Dobsonian
127mm f/12 Orion Apex Mak
102mm f/8.0 Tak TSA Super-APO
066mm f/5.9 WO ZenithStar SD APO
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Brooklyn
scholastic sledgehammer
Reged: 07/24/08
Posts: 870
Loc: Central New Jersey
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So, bill....you found that on ONLY the 5mm, taking off the negative lens group provided a far better viewing experience overall?
I know this can be done with ANY of the baader eyepieces without requiring any additional FTR or other accessories.
Simply take a 5mm or 8mm, take off the negative group, and boom you have a 19-22mm eyepiece?
Say i took a 8mm, and took off the negative to make it a 19-22mm. How will this "frankenstein ep" as someone said before, compare to the retail 21mm eyepiece.
will it have less eye relief and a smaller FOV compared to the retail 21mm WITH negative group?
Its interesting that baaders can be modified both ways, using the 2 FTR to make the focal length smaller, or just removing the negative group to get a much longer focal length.
We know that using FTRs to decrease the FL makes for much shorter eye relief and smaller FOV.
What does going the opposite way do?
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Meade 8.25"(209.55mm) LX-90 EMC (SCT)
Albert Einstein =>
“Intellectual growth should commence at birth and cease only at death.”
“If you can't explain it simply, you don't understand it well enough.”
Edited by Brooklyn (08/07/08 06:41 PM)
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BillP
Carpal Tunnel
Reged: 11/26/06
Posts: 1986
Loc: Vienna, VA
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Quote:
So, bill....you found that on ONLY the 5mm, taking off the negative lens group provided a far better viewing experience overall?
...
Sorry ...not sure which lens group you are referring to. I found that removing only the Smyth group did NOT produce as good a view as removing both the Smyth group and the next doublet above it. There are 8 total lenses in a Hyperion (except the 24mm). Had to remove 1/2 of them before it became not so bad. To do this it is necessary for one to do some EP surgery and break the mid-seal on the 2in housing to unscrew it, then remove the retaining ring and lens cup from the lower half of the 2" housing, and of course leave the 1.25" barrel off with the Smyth group that it contains also.
-Bill
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250mm f/4.7 Orion XT10i Dobsonian
127mm f/12 Orion Apex Mak
102mm f/8.0 Tak TSA Super-APO
066mm f/5.9 WO ZenithStar SD APO
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Brooklyn
scholastic sledgehammer
Reged: 07/24/08
Posts: 870
Loc: Central New Jersey
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alright, i would like to bring your attention to
http://www.alpineastro.com/Hyperion-Eyepieces_com/Images_and_Docs/HyperionandZoomInstructions-Version2.pdf
Go to the table at the bottom and look at 8mm. All the way to the right it says "without first group of lenses."
The 8mm turns into a 21.8mm eyepiece with a field stop of 30mm!! That is a lot more than the normal 10.7mm of field stop that's in the unmodified version.
I called it a negative lens element because that is how it was referred to on one thread that i found (which is listed in this thread up above).
You called it the Smyth group, and the baader website calls it "without first group of lenses."
Are these all the same part/element/group?
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Meade 8.25"(209.55mm) LX-90 EMC (SCT)
Albert Einstein =>
“Intellectual growth should commence at birth and cease only at death.”
“If you can't explain it simply, you don't understand it well enough.”
Edited by Brooklyn (08/08/08 01:30 AM)
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Gaz O'C
Pooh-Bah
Reged: 01/02/05
Posts: 1227
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I have the full set of Hyperions and both fine tuning rings, I can't see that the rings affect the FOV other than in the expected way (ie increasing the mag). The reason I've ended up with the full set is that I don't like fiddling around in the dark with the tuning rings. I also have two 3.5mm Hyperions, one of which always has the 14mm ring in to make a 2.5mm eyepeice, it saves me having to use a barlow to get to x300 and above for lunar work in my 750mm-1000mm scopes.
If you are thinking of getting the full set I'd skip the 21mm as it gives the same FOV as the 17mm. 24mm, 17mm etc is a cheaper way to go IMHO.
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14" f4.5 Dob
10" Meade SCT
180mm f15 Mak/Cass
127mm f12 Mak/Cass
150mm f5 refractor
ED100
EQ6 Skyscan
HEQ5
EQ2
http://stargazerslounge.co.uk/
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Brooklyn
scholastic sledgehammer
Reged: 07/24/08
Posts: 870
Loc: Central New Jersey
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SUCCESS!
The 2 hyperions arrived today, i slept in till 12pm and they were delivered at 9am, so they cooked up in the sun for 3 hours. 
First impression is quite dramatic. The eyepieces are very well made and quite heavy.
One thing i noticed however, it seems that my 5mm was an older production than the 8mm.
The differences were subtle...
The 8mm looked all new and polished and the box that it came in didn't have any dust or scratches on it. You know how you can just SMELL it when optics or other manufactured goods are brand new? they just of that factory lubricant smell, and i love it! Just like new car smell, except new eyepiece smell!
The 5mm came nicely packaged but seemed to have a spec or 2 of some dust on the inside. The box had a couple dents in it, as it is made out of cardboard/hard paper matieral so i guess it was slammed into something or bumped hard but im sure this doesn't affect the inside of the box.
Also, the 5mm did'nt smell as new as the 8mm did.
Neither of the boxes were ever opened. The leather pouches, and all the plastic bags that protect the eyepiece, were all perfectly folded...something i couldn't repeat or recreate when trying to put them back in the box the first time after looking at them.
Which direction are you supposed to rotate to remove the pieces of the eyepiece? I assume it is counterclockwise just as most screwin systems are.
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Meade 8.25"(209.55mm) LX-90 EMC (SCT)
Albert Einstein =>
“Intellectual growth should commence at birth and cease only at death.”
“If you can't explain it simply, you don't understand it well enough.”
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