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Equipment Discussions >> Eyepieces

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Ps191
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Reged: 06/17/09

Loc: E.OR.
Time to ask the experts
      #6260106 - 12/18/13 01:22 PM

Hi everyone, first time posting in the eyepiece form. This may be a longer post so please be patience – I can use the help.

Background
I've observed off and on over the years and after recently finishing school (anyone know of an engineering firm looking to hire) and I'm planning on increasing my time enjoying the sky. Because I was in school my astro budget was practically nil but now since I'm out I'd like to consider a few better eyepieces. I've been reading old post that may be of relevance (made it 25 pages back) as well as doing some searches but am quickly finding myself lost.

Current Equipment Observation Choice
I'm currently using a 12” f/4.9 dob. In the future I'll have a 8” f/7.6 when I can finish putting togeather the ota and mount. Long term goals may include a 15” to 17” sub f/4 telescope. At this point I favor Newtonian reflectors and don't have a coma corrector (yet).
I don't find myself gravitating toward one type of observing but enjoy, galaxy's, open and globular clusters, nebula's, double stars and planets. I really enjoy the widefield views but also use some magnification to observe the details, so while I enjoy planets my primary goal for this discussion is to find eyepieces that work best for deep space objects.
My current eyepiece collection are (all are 1.25”):
- Unknown 1 1/8” (I assume this is a 27.6mm eyepiece otherwise no other markings)
- Meade 25mm (I think this the budget eyepiece Meade send with most of their telescopes)
- Parks 20mm Plossl (would be interesting to know more about this eyepiece)
- Edscorp 12.5mm Or. (see note on Parks)
- Meade 9mm (see note on Meade 25)
- Unknown 22-7.4mm zoom (no other markings)
I use the 1 1/8” for finding objects and general viewing but find it frustrating to not be able to see the Pleiades cluster, the double cluster (Per), or the the majority of the Andromeda galaxy. Most of my close up viewing happens with the 12.5mm, as the 9mm sometime feels like to much magnification but then 20mm is not enough.

Now for Questions and Other Thoughts
It seems like the ES 82deg collection is a good value for the money so my current thought would be to get the ES 30mm for widefield views along with the ES14 and ES11 for closer looks. I may consider a 2x Barlow/extender in the future for planetary nebula and double star observing.
I understand that the ES30mm is huge and heavy and the ES24mm a close contender, but will the ES24mm do what I want. Comparing the two it seems the ES24 is a good widefield eyepiece for 10” scopes, is on the fence for 12” scopes but what about larger scopes? Saving $50 on the ES24mm over the ES30mm is also very attractive.
I know the ES14mm has FC and I don't know if it will bother me, but it still gives me pause. I don't know, but the ES11mm may feel short at times thus the ES14mm, or could I get by with only one (and which one)? Should I be considering other ES 82 deg eyepieces?
Any thoughts? As can be seen I don't have much experience with higher quality, wide-field eyepieces so your experience is appreciated (especially the 12” F/4.9 dob users). Is there other eyepiece (brands, makes, models) I should consider? I know some will say get the Televue____ or the ES__mm 100 deg eyepiece, but at “X” time the cost? If I knew exactly what focal lengths best fit my observing I might be able to budget one longer ES 82deg and one shorter shorter length ES 100deg eyepiece but most Televue are out (even at most used prices). Also the 2” barrel of many of these seem to limit its usefulness in certain scopes not to mention doubling the cost of any future Barlow/extenders. $400 is a comfortable budget top and $500 is pushing it, but doable, if it gets me set for my life.

I feel like I have analysis paralysis - maybe I should just go observe (and be thankful) with what I have and forget this whole mess


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gene 4181
scholastic sledgehammer


Reged: 11/12/13

Loc: n.e. ohio
Re: Time to ask the experts new [Re: Ps191]
      #6260159 - 12/18/13 01:56 PM

don't worry. you want the widest fov. get the 30. the 24 is nice but for what you want, its the 30. and get the 14. nice field of view, not to high of power, and it will barlow well for a 7 mm. terrence dickson once said about paraylisis. buy it use it and see where you want to go from there. i see the 11 mm being a single use piece. later you can fill in between. i look at eyepieces in terms of exit pupil and my light pollution and what works.

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Starman1
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Reged: 06/24/03

Loc: Los Angeles
Re: Time to ask the experts new [Re: gene 4181]
      #6260221 - 12/18/13 02:29 PM

Well, don't go overboard on eyepieces. The wider the apparent fields of view, the farther apart the magnifications can be because when you step up in power the fields don't get as small. If the field of view of a medium power eyepiece is big enough, you can actually use the same eyepiece for "finding" as you do for "observing".

In a 12" (about the same size and f/ratio as my 12.5" f/5), you could use the 1X/2X/3X protocol to pick some reasonable wide field eyepieces.
In your size scope, that would be 70x, 140x, 210x and then either add a good barlow for 280X and 420X or think about another eyepiece.

In your instrument, with its 1500mm focal length, that would be eyepieces of
21mm, 10-11mm, 7-8mm, and a good 2X Barlow.

Let's come up with some possibles:
Economy widefields:
--ES 24mm x 82
--ES 11mm x 82
--ES 8.8mm x 82
--ES 2X 1.25" Focal Extender

Medium price widefields, choice 1:
--ES 20mm x 100
--ES 14mm x 100
--ES 9mm x 100
--ES 2X, 2" Focal Extender

Medium price widefields, choice 2:
--TeleVue Nagler T5 20mm x 82
--TeleVue Nagler T6 11mm x 82
--TeleVue Nagler T6 7mm x 82
--TeleVue 2X, 1.25" Barlow.

Medium price widefields, choice 3:
--ES 20mm x 100
--TeleVue Delos 10mm x 72
--TeleVue Nagler T6 7mm x 82
--TeleVue 2X, 1.25" Barlow or TeleVue 2.5X, 1.25" PowerMate

High price widefields
--TeleVue Ethos 21mm x 100
--TeleVue Ethos 10mm X 100
--TeleVue Nagler 7mm x 82
--TeleVue 2X, 2" PowerMate

I put a 2" Powermate in the last selection because it is easier to use with a Paracorr, which you might want with the 12" and definitely will need on the larger scopes planned.
Note that, at f/5, all the above eyepieces will work great. At f/4 and below the edge of field issues begin to show with most eyepieces and you will want to move to eyepieces fully corrected at short f/ratios.

I'm sure other posters will quickly chime in about what you need.


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JustaBoy
Carpal Tunnel


Reged: 06/19/12

Re: Time to ask the experts new [Re: gene 4181]
      #6260231 - 12/18/13 02:34 PM

"$400 is a comfortable budget top and $500 is pushing it, but doable, if it gets me set for *my life*"


You're kidding, right?

Sorry, but this is the Eyepiece Forum:-)


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howard929
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Reged: 01/02/11

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Re: Time to ask the experts new [Re: Ps191]
      #6260250 - 12/18/13 02:44 PM

Price verses performance appears to be on a per case basis. From a 100 degree ES being tromped by a Delos, a ES 82 being only as good as 80 percent of a Nagler to I couldn't tell the difference. Buy one eyepiece in the more expensive class, just one, use it and find out what you think of it.

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JustaBoy
Carpal Tunnel


Reged: 06/19/12

Re: Time to ask the experts new [Re: howard929]
      #6260254 - 12/18/13 02:47 PM



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Lorence
scholastic sledgehammer


Reged: 09/15/08

Re: Time to ask the experts new [Re: Ps191]
      #6260263 - 12/18/13 02:50 PM

Quote:

I really enjoy the widefield views but also use some magnification to observe the details, so while I enjoy planets my primary goal for this discussion is to find eyepieces that work best for deep space objects.




Take a look at what some people are doing with their astro video cameras before you spend more on eyepieces.

http://www.nightskiesnetwork.com/

I have a collection of eyepieces that are better than adequate. The only thing they are collecting now is dust.

That collection was over fifty years in the making. I have seen and enjoyed observing more in the few years I have used my Mallincams than I have in all the years before.


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Jeff Morgan
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Reged: 09/28/03

Loc: Prescott, AZ
Re: Time to ask the experts new [Re: JustaBoy]
      #6260265 - 12/18/13 02:52 PM

Quote:

"$400 is a comfortable budget top and $500 is pushing it, but doable, if it gets me set for *my life*"


You're kidding, right?

Sorry, but this is the Eyepiece Forum:-)






But seriously, if you are looking to be set "for life" then buy the best for DSO work (Tele Vue Delos or Pentax XW) immediately and avoid the transaction costs of trading up later.

The key is not falling for the trap of buying the whole set, or having to have it all now. Buy one or two of the best, and perhaps a barlow and be patient for more available budget. Your existing eyepieces can supplement the range of focal lengths short term.

Utilizing the used market can help greatly in this - used XW and Delos are in the $225-$275 range currently.

Selling a few (eventually all) of your starter eyepieces can help you stretch a bit further. Getting hired into your profession will help quite a bit more, best of luck on that!


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JustaBoy
Carpal Tunnel


Reged: 06/19/12

Re: Time to ask the experts new [Re: Jeff Morgan]
      #6260274 - 12/18/13 02:55 PM



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gene 4181
scholastic sledgehammer


Reged: 11/12/13

Loc: n.e. ohio
Re: Time to ask the experts new [Re: Ps191]
      #6260451 - 12/18/13 04:24 PM

you said you'd like to see the pleides and andromeda and double cluster . 30 mm the rest, i'll defer to my esteemed collegues

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Starman1
Vendor (EyepiecesEtc.com)
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Reged: 06/24/03

Loc: Los Angeles
Re: Time to ask the experts new [Re: gene 4181]
      #6260553 - 12/18/13 05:23 PM

True field in the 30mm ES will be 1.64 degrees. That's large enough for most large targets--not quite large enough to see ALL of the Pleiades or North America Nebula or California nebula or Veil nebula, etc., but certainly large enough for just about everything else. And large enough to see major portions of the really big things.

A note to consider, however, is that just about every object in the sky is a degree in diameter or smaller. Purchasing an eyepiece just for the 10-20 objects that are a bit larger seems like it would be a "supplemental" purchase for later, when filling in the "in-between" sizes and magnifications.
The 24mm x 82 ES would yield a true field of 1.28 degrees, which is still very large, and the magnification would be better for a much larger number of objects.


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gene 4181
scholastic sledgehammer


Reged: 11/12/13

Loc: n.e. ohio
Re: Time to ask the experts new [Re: Starman1]
      #6260800 - 12/18/13 07:31 PM

well then, i would say to get yourself a small refractor then to see all the pleides, those huge sprawling star clouds thru cygnus, and andromeda galaxy. i guess a 12 dobs not the best for huge swaths of sky.

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JustaBoy
Carpal Tunnel


Reged: 06/19/12

Re: Time to ask the experts new [Re: gene 4181]
      #6260804 - 12/18/13 07:35 PM

I have larger scopes, but I could not get along well without my ST-80. - My most used by far!

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SeattleScott
Pooh-Bah


Reged: 10/14/11

Re: Time to ask the experts new [Re: JustaBoy]
      #6261105 - 12/18/13 11:48 PM

Vixen LVW series are reported to be the best series for observing down to F4 without a coma corrector. Sub F4 and there is probably no getting around a Paracorr. Used LVW prices are about $150 to $175 which is significantly cheaper than Pentax XW or Delos, the two competing brands. In astronomy you end up paying real money for minute differences in performance with the top of the line stuff. ES may be the best value in terms of coming close to the top brands and being quite a bit less, and ES will work fine at F4.9. But if you go much lower, LVW or a Paracorr will work better.

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ibase
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Reged: 03/20/08

Loc: Manila, Philippines 121*E 14*N
Re: Time to ask the experts new [Re: Ps191]
      #6261136 - 12/19/13 12:12 AM

One thing immediately noticed is that the current EP arsenal lacks widefields (68-70-deg. AFOV up). Just a suggestion, leapfrog over 70 & 80-deg widefields and get your feet wet with a 14mm ES-100, that way, you'll be avoiding the FC dilemma in the 14mm 82-deg. too.



The majestic expansive view the 100 yields on a big scope is an unforgettable wow moment.

Best,


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TechPan6415
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Reged: 07/29/12

Loc: Aspen, Co
Re: Time to ask the experts new [Re: Lorence]
      #6261283 - 12/19/13 03:18 AM

Quote:

Take a look at what some people are doing with their astro video cameras before you spend more on eyepieces.




That's like saying "Take a look at what some people are doing with Garage Band on their computers before you spend money on a Martin Acoustic."


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csrlice12
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Reged: 05/22/12

Loc: Denver, CO
Re: Time to ask the experts new [Re: TechPan6415]
      #6261453 - 12/19/13 08:31 AM

Regarding your other question; the Denver, CO area has lots of company's looking/hiring engineers. We have Lockheed Martin, CH2M Hill, Ball, Raytheon, and numerous other smaller firms in the area. Not a bad place to live either...we've had a bad last year of viewing though, but who hasn't.....we also have something many places don't....a brick and morter astronomy store, not just a camera store with a couple of scopes, but a real telescope shop will very knowledeable people, who are also active astronomers.....

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Ps191
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Reged: 06/17/09

Loc: E.OR.
Re: Time to ask the experts new [Re: csrlice12]
      #6262028 - 12/19/13 02:18 PM

Wow, thanks everyone for the great thoughts, suggestions and help. I was gone most of yesterday so I'll try and catch up. I've been using N.A.A. Telescope Math Calculator to find the true field of view and Stellarium to compare what these fields of view would look like with different objects, this has been helpful.

@ gene4181 - Thanks for the reminder to buy used, almost all of my equipment has been purchased used and I'll certainly plan for more used equipment in the future. Would you mind clarifying the thought of "the 11 mm being a single use piece".
@ Starman1 - Thanks for assembling those list and for clarifying why you suggest the 24mm over the 30mm. This has been good food for thought and very helpful.
@ JustaBoy - I know this is the eyepiece forum, but I tend to be a minimalist with the thought that "less is more (manytimes)" and "if I don't used it, lose it". I've been interested in the night sky for over 20 years, about half of that time using a star wheel and binoculars (with an occasional borrowed C8), of the remaining time most of it was happily spent with only 3 eyepieces. I suspect that a few of the eyepieces from my list will find a new home if I get anymore.
@ howard929 - Thanks, so it sounds like used is the preferred way to go, while figuring out what will work best. Is ES considers the expensive class or are you thinking of TV?
@ Lorence - I've thought about astro video cameras and I would like to see one someday, but at this time I appreciate the simplicity of my dob with its few power requirements. Also if I'm going to be using electrons to create an images why not jump in all the way in AP with a dedicated CCD?
@ Jeff Morgan - Thanks I don't few pushed to buy complete sets which is why I'm asking here before buying the ones that will work the best. Also considering I spent years with simple eyepieces so most any choice will be an upgrade that should keep me happy for a vary long time, or is this a slipper slop? Maybe the key is not to look through more expensive eyepieces?
@ SeattleScott - Thanks I'll have to read more about the Vixen LVW, either way I'm leaving the future open to a Paracorr.
@ ibase - If you took that picture then you would have both the 100 and 82 deg. Would you care to share your thoughts comparing the two?
@ csrlice12 - Thanks for the ideas. I've looked for jobs in Denver area in the past, but it may be time to revisit the possibilities.

I did remembered I have one more eyepiece that should be somewhere on the way, a Lunt 10mmm - 70deg. I don't know how I'll like this eyepiece but it should be better then much of what I have.
So now I'm considering the ES 24mm-82 and the ES 14mm-82 (preferably used) with a 2x barlow/extender in the future.
If the ES 30mm-82 would be available used before the ES24mm-82 should I still consider it?
Howabout a used ES14mm-100 instead of the ES14mm-82? The ES14mm-100 would have a 0.94deg true field and the ES24mm-82 would have 1.3deg true field, is this too close of overlap?
Finally with the Lunt 10mm in the mix should I skip the 14mm rang and thing about something in the 6mm to 8mm range?

As always I appreciate the great suggestions and thoughts.


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Ps191
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Reged: 06/17/09

Loc: E.OR.
Re: Time to ask the experts new [Re: Ps191]
      #6262090 - 12/19/13 02:47 PM

I should add that while I enjoy the wide field views I'm not looking for a rich field view from a 12" F/4.9. Rich field views will have to remain the domain of my binoculars or another telescope.

Concerning my quest for a better eyepiece, I don't have an AM account but maybe I'll post a wanted add here on CN and see what comes. This is by no means the end, so keep the thoughts and suggestions coming.


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Starman1
Vendor (EyepiecesEtc.com)
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Reged: 06/24/03

Loc: Los Angeles
Re: Time to ask the experts new [Re: Ps191]
      #6262104 - 12/19/13 02:54 PM

Kevin,

The html code behind that calculator uses the formula:
1) TF = AF/M to calculate True Field.
AF = Apparent Field
M = Magnification.

This will result in very slightly larger than actual true fields when calculated.

You may have read that a slightly more accurate formula to use is:
2) TF = (FSEP/TFL) * 57.296
where FSEP = field stop of eyepiece
and TFL = Telescope focal length.

How much difference does it make?

Let's see:

My Telescope has an effective focal length of 1825.6mm
If I use a 21 Ethos, the magnification is 86.93 and the field stop of that eyepiece is 36.2mm.

Using formula 1, the true field is 100/86.93 = 1 degree 9 minutes
Using formula 2, the true field is (36.2/1825.6)*57.296 = 1 degree 8 minutes.

That difference is really small.

The only point I'd make is that IF you know the field stop diameter, use formula 2. Otherwise, use formula 1.


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Jeff Morgan
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Reged: 09/28/03

Loc: Prescott, AZ
Re: Time to ask the experts new [Re: Ps191]
      #6262117 - 12/19/13 03:03 PM

Quote:

@ Jeff Morgan - Thanks I don't few pushed to buy complete sets which is why I'm asking here before buying the ones that will work the best. Also considering I spent years with simple eyepieces so most any choice will be an upgrade that should keep me happy for a vary long time, or is this a slipper slop? Maybe the key is not to look through more expensive eyepieces?






Well, perhaps the only thing not debatable on the Eyepiece Forum is that expensive eyepieces spoil you. In most all cases you get what you pay for.

If I understand your question correctly, yes getting something like a Delos or Pentax XW could be a "final destination" (if there is such a thing in eyepieces), unless you find out you crave more field as some do. Only one person holds that answer and getting out to a club observing session or star party will help you answer that question before you start spending money.


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Lorence
scholastic sledgehammer


Reged: 09/15/08

Re: Time to ask the experts new [Re: TechPan6415]
      #6262155 - 12/19/13 03:25 PM

Quote:

Quote:

Take a look at what some people are doing with their astro video cameras before you spend more on eyepieces.




That's like saying "Take a look at what some people are doing with Garage Band on their computers before you spend money on a Martin Acoustic."




Selling horseshoes in Detroit seems a bit more appropriate. Any bets more people have played some sort of Garage Band than have played a Martin, or even know what a Martin is.

To make a comparison like you have suggests you have not seen what people are doing with electronic eyepieces. I'm under the impression that the original poster would be open minded enough to realize that.


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Ralph Steudtner
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Reged: 07/13/12

Re: Time to ask the experts new [Re: Ps191]
      #6262236 - 12/19/13 04:13 PM

Hi Kevin

Since we have similar scopes I'll throw in my 2 cents worth on your eyepiece choices as well. I personally find that in my 12" Dobs my most frequently used focal lengths to view the types of objects you like to view are 14mm and 10mm. Since that is the case for me if I were only going to choose 1 or 2 eyepieces, I would concentrate most of my money on those focal lengths. You seem to like the wide field views, however, so that would dictate at least one of your 2 eyepieces at a longer focal length.

Of the many choices mentioned my 2 choices ( and I have both) would be the ES 100/14 and the ES 82/24. You said you want to view the double cluster. My ES 100/14 gives me the best view of the double cluster I have ever seen. There is something about the afov, exit pupil and magnification using that eyepiece in my 12" Dobs that is truly exceptional. It also does an excellent job on many other DSO's as well. I would also choose the 100 degree fov in that focal length over the 82 degree.
For my low power eyepiece I chose the ES 82/24. It provides an afov more than sufficient to view most of the objects you will want to see. In addition, when you complete your 8" Dobs the ES 82/24 will give you the same afov as the ES 82/30 will in your 12" for viewing those larger objects. The 24mm also has an advantage in weight, cost and magnification over the 30mm.

When you begin looking for higher magnification eyepieces there are many excellent choices to choose from. For now though, I think you would be very pleased with those choices.

Ralph


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TechPan6415
sage
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Reged: 07/29/12

Loc: Aspen, Co
Re: Time to ask the experts new [Re: Lorence]
      #6262332 - 12/19/13 05:14 PM

Quote:

To make a comparison like you have suggests you have not seen what people are doing with electronic eyepieces. I'm under the impression that the original poster would be open minded enough to realize that.




I have spent the last 20 years of my 24 years as a professional photographer using digital, far, far longer than most and I am nearly done with it. What I have seen this technology do to people by and large is not good. In fact, I have been on a panel of DC based think tanks for the past 4 years as I did a project that had the unintended consequences of watching people go from having eye contact to being a bunch of rude idiots.

So yeah, I understand what you are talking about...I am 1,000% against it and actually plan to fight it. It's yet one *more* thing to use a device on instead of being tactile in seeing the oldest light of the farthest objects your soul will ever set eyes on.

If someone said they would pay me a million dollars to use gadgets instead of real eyepieces, I would tell them to donate the money to a good charity and get lost!

There is simply no substitute for seeing something with your own two eyes, through a telescope, refracted water, a reflection or otherwise. That is what this hobby is all about, not this new fangled fad of "Photoshopped Photons".

********************

Back on topic, to the OP of this thread:

If I could only have 3 of the 8 eyepieces I own, I would keep my ES 100 25mm, ES 100 14mm and soon to arrive Nagler zoom 3-6mm. But if only one, the 14mm 100, it's by far my favorite.


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gene 4181
scholastic sledgehammer


Reged: 11/12/13

Loc: n.e. ohio
Re: Time to ask the experts new [Re: Ps191]
      #6262507 - 12/19/13 07:22 PM

i only recommended my thoughts following your price of 400 dollars. you mentioned pleides, double cluster and andromeda galaxy. you mentioned 30 mm 82. and of the 2, 14 mm and 11 mm. i thought the 14 might be better for a scope of 1500 mm. it could double as a 7 mm with the barlow and be usable on average nights. i didn't think the 11 mm would be usable most nights barlowed. but if it would with your location and conditions, my bad.

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Ps191
super member
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Reged: 06/17/09

Loc: E.OR.
Re: Time to ask the experts new [Re: Starman1]
      #6262533 - 12/19/13 07:38 PM

Quote:

Kevin,

The html code behind that calculator uses the formula:
1) TF = AF/M to calculate True Field.
AF = Apparent Field
M = Magnification.

This will result in very slightly larger than actual true fields when calculated.

You may have read that a slightly more accurate formula to use is:
2) TF = (FSEP/TFL) * 57.296
where FSEP = field stop of eyepiece
and TFL = Telescope focal length.

How much difference does it make?

Let's see:

My Telescope has an effective focal length of 1825.6mm
If I use a 21 Ethos, the magnification is 86.93 and the field stop of that eyepiece is 36.2mm.

Using formula 1, the true field is 100/86.93 = 1 degree 9 minutes
Using formula 2, the true field is (36.2/1825.6)*57.296 = 1 degree 8 minutes.

That difference is really small.

The only point I'd make is that IF you know the field stop diameter, use formula 2. Otherwise, use formula 1.




Thanks, it is always good to know the formulas behind the answers. It might be time to set up a spreadsheet.


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Ps191
super member
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Reged: 06/17/09

Loc: E.OR.
Re: Time to ask the experts new [Re: Jeff Morgan]
      #6262540 - 12/19/13 07:44 PM

Quote:

Quote:

@ Jeff Morgan - Thanks I don't few pushed to buy complete sets which is why I'm asking here before buying the ones that will work the best. Also considering I spent years with simple eyepieces so most any choice will be an upgrade that should keep me happy for a vary long time, or is this a slipper slop? Maybe the key is not to look through more expensive eyepieces?






Well, perhaps the only thing not debatable on the Eyepiece Forum is that expensive eyepieces spoil you. In most all cases you get what you pay for.

If I understand your question correctly, yes getting something like a Delos or Pentax XW could be a "final destination" (if there is such a thing in eyepieces), unless you find out you crave more field as some do. Only one person holds that answer and getting out to a club observing session or star party will help you answer that question before you start spending money.




I did make it to OSP once a few years back, I felt like a child in a candy shop. The good thing is that I have skies as dark, are darker, then OSP when the weather cooperates, the down side is that the closest club is a good three hours away. I guess CN will have to be my club - welcome aboard everyone


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Ps191
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Re: Time to ask the experts new [Re: Ralph Steudtner]
      #6262555 - 12/19/13 07:54 PM

Quote:

Hi Kevin

Since we have similar scopes I'll throw in my 2 cents worth on your eyepiece choices as well. I personally find that in my 12" Dobs my most frequently used focal lengths to view the types of objects you like to view are 14mm and 10mm. Since that is the case for me if I were only going to choose 1 or 2 eyepieces, I would concentrate most of my money on those focal lengths. You seem to like the wide field views, however, so that would dictate at least one of your 2 eyepieces at a longer focal length.

Of the many choices mentioned my 2 choices ( and I have both) would be the ES 100/14 and the ES 82/24. You said you want to view the double cluster. My ES 100/14 gives me the best view of the double cluster I have ever seen. There is something about the afov, exit pupil and magnification using that eyepiece in my 12" Dobs that is truly exceptional. It also does an excellent job on many other DSO's as well. I would also choose the 100 degree fov in that focal length over the 82 degree.
For my low power eyepiece I chose the ES 82/24. It provides an afov more than sufficient to view most of the objects you will want to see. In addition, when you complete your 8" Dobs the ES 82/24 will give you the same afov as the ES 82/30 will in your 12" for viewing those larger objects. The 24mm also has an advantage in weight, cost and magnification over the 30mm.

When you begin looking for higher magnification eyepieces there are many excellent choices to choose from. For now though, I think you would be very pleased with those choices.

Ralph




Thanks, sound like the ES14mm-100 is a winner, I'll have to see if anyone want to part with theirs and it will have to be used or I will not be able to buy at all.
I did see a 13mmT6 Nagler in the classifieds for $225. Would any of you ES14mm-100 owners part with your ES for a 13mmT6 Nagler


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Ps191
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Re: Time to ask the experts new [Re: gene 4181]
      #6262561 - 12/19/13 07:58 PM

Quote:

i only recommended my thoughts following your price of 400 dollars. you mentioned pleides, double cluster and andromeda galaxy. you mentioned 30 mm 82. and of the 2, 14 mm and 11 mm. i thought the 14 might be better for a scope of 1500 mm. it could double as a 7 mm with the barlow and be usable on average nights. i didn't think the 11 mm would be usable most nights barlowed. but if it would with your location and conditions, my bad.




About the barlowed 11mm your probably right, I live among the mountains so the seeing is not always that steady. Thanks for adding your observations to this thread.


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ibase
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Re: Time to ask the experts new [Re: Ps191]
      #6262657 - 12/19/13 09:07 PM

Quote:


@ ibase - If you took that picture then you would have both the 100 and 82 deg. Would you care to share your thoughts comparing the two?





Yes, I have both of these 14mm's. The obvious difference is the bigger field (by 22%) on the ES-100 14mm (and it's bulkier/heavier too), and unlike the 82, field curvature is no problem where the latter (82) suffers from what I would categorize as "mild" FC, not so objectionable or a deal breaker but it's there. Reports about the FC on the 82 are all over the place, probably a function of the ability of one's individual eye to adjust or compensate for FC. On axis there's not much of a difference, maybe just a tad sharper on the 100. And the 100 is 2" format, while the 82 is 1-1/4". Aesthetically, the 100 wins hands down with its enthralling & majestic views.


Underbelly of 100ES14mm (left) & 82ES14mm

Best,


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SeattleScott
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Re: Time to ask the experts new [Re: ibase]
      #6262694 - 12/19/13 09:32 PM

The beauty of hyper wides is in the eye of the beholder. I stargazed once with a guy who had a 41 Pan, 31Nagler and 21 Ethos. We both agreed that we liked the nagler better than the Ethos because our eyes couldn't take in that wide of a FOV so there was a sense that it was being wasted. Personally my eyes can take in about an 80 deg AFOV so 82 deg is perfect for me. Spacewalk effect with virtually no wasted FOV. Some people prefer super wides like Panoptics, Pentax, Delos, LVW etc because their eyes can only take in a 70 deg FOV or so. Others claim to be able to take advantage of a 100 deg FOV.
DISCLAIMER the guy whose ethos I looked thru had a tracking scope, not a Dob. My scopes are all able to be mounted on a tracking eq mount. If you have a non tracking scope, hyper wides are of value even if you cannot take in the entire FOV because they allow you to study an object longer before it drifts out of view. Just realize they can get very big and heavy, effecting the scopes balance. If your telescope falls over when you insert an eyepiece, your eyepiece is too heavy!


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csrlice12
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Re: Time to ask the experts new [Re: SeattleScott]
      #6263210 - 12/20/13 08:55 AM

The whole idea of the 100* (and wider) Hyperwides is that you "don't" see the field stop. You see the object in the context of the night sky around it. The 100* aren't really designed for tracking an object from field stop to field stop, they're designed for the expansive view. You're not supposed to view the entire fov, the idea is to get the field stop out of the way.....

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Ps191
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Re: Time to ask the experts new [Re: SeattleScott]
      #6263788 - 12/20/13 01:54 PM

Quote:

If you have a non tracking scope, hyper wides are of value even if you cannot take in the entire FOV because they allow you to study an object longer before it drifts out of view.




Yep, my scope is none tracking and I often view with others who are not familiar with telescopes so having a wide field of view would be an advantage - I think (as I have little to no experience with eyepieces over 60degs).

Quote:

Just realize they can get very big and heavy, effecting the scopes balance.




This is one reason I'm thinking more about the ES24mm vs the ES30mm. I still may have to add weight for balancing, but that is doable.

Quote:

If your telescope falls over when you insert an eyepiece, your eyepiece is too heavy!




Na, I just need a bigger scope with better balance


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Ps191
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Re: Time to ask the experts new [Re: csrlice12]
      #6263790 - 12/20/13 01:56 PM

Quote:

The whole idea of the 100* (and wider) Hyperwides is that you "don't" see the field stop. You see the object in the context of the night sky around it. The 100* aren't really designed for tracking an object from field stop to field stop, they're designed for the expansive view. You're not supposed to view the entire fov, the idea is to get the field stop out of the way.....




Sounds great I'll take your word for it. Hopefully I'll be able to have experienced this in the future.


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Ps191
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Re: Time to ask the experts new [Re: Ps191]
      #6263803 - 12/20/13 02:01 PM

ES14mm(100) vs. 13mmT6(82) Nagler

I would still like to hear if any ES14mm-100 owners would part with their ES for a 13mmT6 Nagler or vis versa.


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csrlice12
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Re: Time to ask the experts new [Re: Ps191]
      #6263918 - 12/20/13 03:00 PM

Don't have a 13T6, but do have other Televues...and the only thing I'd replace the ES 100* 14mm with would be the 13Ethos....The ES 14mm is the best of the ES 100 lineup. The 20mm is also good, still waiting on the 9 (but reports are good), the 5.5 has eyelash territory eye relief, but the views are good.

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hfjacinto
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Re: Time to ask the experts new [Re: Ps191]
      #6263937 - 12/20/13 03:08 PM

Quote:

ES14mm(100) vs. 13mmT6(82) Nagler

I would still like to hear if any ES14mm-100 owners would part with their ES for a 13mmT6 Nagler or vis versa.




I have both and currently use the 14MM ES 100* more. I only keep the 13MM as its 1.25" and my current largest 1.25" eyepiece (not including the binoviewer sets).


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BillP
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Re: Time to ask the experts new [Re: Lorence]
      #6263968 - 12/20/13 03:30 PM

Quote:

Take a look at what some people are doing with their astro video cameras before you spend more on eyepieces....I have seen and enjoyed observing more in the few years I have used my Mallincams than I have in all the years before.




You make an interesting point. Especially now with the Mallincam Jr which is priced around $599, or equal to one expensive 100 degree eyepiece, or 6 very good Plossls/Abbes.

Of course eViewing is not the same experience as visual viewing, but it certainly has its own set of merits that only it can do, expanding the capability in a way that the conventional eyepiece never will be able to. The winds of change are definitely blowing, and something to seriously consider for those considering the hobby.


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JustaBoy
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Re: Time to ask the experts new [Re: BillP]
      #6264047 - 12/20/13 04:18 PM

Bill,

I hope I'm dead before this happens.


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Jeff Morgan
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Re: Time to ask the experts new [Re: BillP]
      #6264053 - 12/20/13 04:19 PM Attachment (15 downloads)

Quote:

Of course eViewing is not the same experience as visual viewing, but it certainly has its own set of merits that only it can do, expanding the capability in a way that the conventional eyepiece never will be able to. The winds of change are definitely blowing, and something to seriously consider for those considering the hobby.




I recall the early days of the "Cookbook Camera" and how coarse the images looked. Couldn't hold a candle to film. Fast forward to today, CCD's have the resolution, film is dead.

Yes, Mallicam is different - fundamentally different - than visual. But it offers great promise and betting against electronics has been a losing bet. It will be an interesting future.

Someone in the local club invited me over last September to walk me through his Mallincam set-up on an 8" SCT. Here is a 6 second exposure (perhaps it was 12 seconds?) of M8 with the moon approximately 6 degrees away. This is just a snapshot from my iPhone of his CRT monitor. The monitor itself was a $9 thrift store special:


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Starman1
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Re: Time to ask the experts new [Re: Jeff Morgan]
      #6264077 - 12/20/13 04:30 PM

Compared to a visual image through a narrowband filter at a dark site, this image:
--displays color you wouldn't see in the visual image.
--displays a seriously compressed gray scale range compared to a visual image. A visual image would have a wider dynamic range.
--has the center area burned out (wouldn't be true in a visual image)
--has a little less than the extent the nebula would have visually (I tracked it out to past 2 degrees visually in my 8" SCT).

But that wouldn't have been true visually with the Moon only a few degrees away.

Anyway, like normal, I'm not impressed. It looks like a rather poor astrophotograph, and it has no resemblance to a visual image. Longer image length would show more, of course.
--


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JustaBoy
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Re: Time to ask the experts new [Re: Starman1]
      #6264142 - 12/20/13 05:02 PM

I want to See it Myself - With my Own Eyes!

Pictures of any kind are only dead representations of reality.

Certainly they have their uses and I like looking at the ones the guys here take, but it's nothing at all like 'being there', looking at the light that has been on a journey of thousands of years. - Just for me.

For you too, If you care to look...


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Ralph Steudtner
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Re: Time to ask the experts new [Re: Ps191]
      #6264304 - 12/20/13 06:50 PM

Quote:

ES14mm(100) vs. 13mmT6(82) Nagler

I would still like to hear if any ES14mm-100 owners would part with their ES for a 13mmT6 Nagler or vis versa.





I have both the ES 100/14 and the 13T6. The 13T6 is a fine eyepiece. It is lightweight and shows tack sharp star images across the entire 82 degree fov. When compared to the ES 100/14, however, it just does not have that "WOW" factor for me. If I could only have one of the 2 eyepieces I would definitely choose the ES 100/14. It gets far more time in the focuser than my 13T6.


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BillP
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Re: Time to ask the experts new [Re: Jeff Morgan]
      #6264357 - 12/20/13 07:42 PM

Jeff,

Yes, it can be quite exciting to see some of these targets so brightly rendered. The Mallincam Jr supports S-VHS output which I believe is around twice standard TV resolution. Would be interesting to see its output image in the field on something like a 9" or 12" monitor that can support that resolution level. Would expect it can be quite impressive. No large aperture scope is ever going to show that color visually I am strongly considering the new Jr model as its price point is fabulous! Heck, I have single eyepieces that cost about that much!

Would be an interesting setup to have a dual scope setup, whatever one's normal visual scope is then piggyback a small 80mm or 92mm with a Mallincam on it so one had dual display all the time, eyepiece and screen. It's exciting to think what it will evolve to with the newer chips developed and newer displays.


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Ps191
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Re: Time to ask the experts new [Re: BillP]
      #6264465 - 12/20/13 08:57 PM

Thanks csrlice12, hfjacinto and Ralph Steudtner for weighing in on the ES14mm(100) vs. the 13mmT6 Nagler, I appreciate you taking the time to help a newbie like me.
At this time I'm planning to try and find a used ES24mm(82) and ES14(100), this sounds like the best view that still fits within my budget. I got a wanted add up - now to find someone willing to sell one or the other, or both. Let the observing begin


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Jeff Morgan
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Re: Time to ask the experts new [Re: Starman1]
      #6265356 - 12/21/13 02:03 PM

Quote:

Compared to a visual image through a narrowband filter at a dark site, this image:
--displays color you wouldn't see in the visual image.
--displays a seriously compressed gray scale range compared to a visual image. A visual image would have a wider dynamic range.
--has the center area burned out (wouldn't be true in a visual image)
--has a little less than the extent the nebula would have visually (I tracked it out to past 2 degrees visually in my 8" SCT).

But that wouldn't have been true visually with the Moon only a few degrees away.

Anyway, like normal, I'm not impressed. It looks like a rather poor astrophotograph, and it has no resemblance to a visual image. Longer image length would show more, of course.
--




More or less what I concluded too. I'm not exactly rushing out to buy a Mallicam (yet).

But as a "look ahead" it does offer some intriguing things:

1) This was a cell phone camera .jpeg snapshot of a low-res NTSC CRT screen. The live image did look better (somewhat). Just like the early CCD's this detector technology will improve, and getting a higher resolution display will be trivial;

2) It was done from the middle of city;

3) It extends observing into the lunar month. Narrow band filter or not, you wouldn't see those extents visually through the same aperture with the first quarter moon six degrees away; and

4) For those that do outreach it would be an awesome tool. Multiple simultaneous viewers, photopic vision. John Q. Public knows nothing about dark adaptation and threshold vision. (Good thing too, because with Mallicam dark adaptation is out of the question!)


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Jeff Morgan
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Re: Time to ask the experts new [Re: BillP]
      #6265367 - 12/21/13 02:09 PM

Quote:

Jeff,

Yes, it can be quite exciting to see some of these targets so brightly rendered. The Mallincam Jr supports S-VHS output which I believe is around twice standard TV resolution. Would be interesting to see its output image in the field on something like a 9" or 12" monitor that can support that resolution level. Would expect it can be quite impressive. No large aperture scope is ever going to show that color visually I am strongly considering the new Jr model as its price point is fabulous! Heck, I have single eyepieces that cost about that much!

Would be an interesting setup to have a dual scope setup, whatever one's normal visual scope is then piggyback a small 80mm or 92mm with a Mallincam on it so one had dual display all the time, eyepiece and screen. It's exciting to think what it will evolve to with the newer chips developed and newer displays.




More resolution is definitely needed, I have not looked at the Jr. I didn't realize that had gotten that cheap! I just spent $900 on a Leica ASPH this week.

Not to hijack the thread any further with this electronic eyepiece future stuff, but this time of year the idea of having the scope outside with me and display inside by the fireplace has some real appeal. Brrrrr.


Edited by Jeff Morgan (12/21/13 02:13 PM)


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faackanders2
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Re: Time to ask the experts new [Re: Starman1]
      #6266154 - 12/21/13 10:47 PM

Quote:

True field in the 30mm ES will be 1.64 degrees. That's large enough for most large targets--not quite large enough to see ALL of the Pleiades or North America Nebula or California nebula or Veil nebula, etc., but certainly large enough for just about everything else. And large enough to see major portions of the really big things.

A note to consider, however, is that just about every object in the sky is a degree in diameter or smaller. Purchasing an eyepiece just for the 10-20 objects that are a bit larger seems like it would be a "supplemental" purchase for later, when filling in the "in-between" sizes and magnifications.
The 24mm x 82 ES would yield a true field of 1.28 degrees, which is still very large, and the magnification would be better for a much larger number of objects.




A 40mm 70 AFOV (or 41mm 68 AFOV Panoptic) would provided the widest TFOV for a 2"(48mm) barrell. I had this before I got a 30mm 82 AFOV and used it as my finder eyepiece, I may still be using it slightly more than the 30mm 82 AFOV for the large or multiple objects.


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karstenkoch
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Re: Time to ask the experts new [Re: TechPan6415]
      #6266198 - 12/21/13 11:38 PM

Quote:

Quote:

To make a comparison like you have suggests you have not seen what people are doing with electronic eyepieces. I'm under the impression that the original poster would be open minded enough to realize that.




I have spent the last 20 years of my 24 years as a professional photographer using digital, far, far longer than most and I am nearly done with it. What I have seen this technology do to people by and large is not good. In fact, I have been on a panel of DC based think tanks for the past 4 years as I did a project that had the unintended consequences of watching people go from having eye contact to being a bunch of rude idiots.

So yeah, I understand what you are talking about...I am 1,000% against it and actually plan to fight it. It's yet one *more* thing to use a device on instead of being tactile in seeing the oldest light of the farthest objects your soul will ever set eyes on.

If someone said they would pay me a million dollars to use gadgets instead of real eyepieces, I would tell them to donate the money to a good charity and get lost!

There is simply no substitute for seeing something with your own two eyes, through a telescope, refracted water, a reflection or otherwise. That is what this hobby is all about, not this new fangled fad of "Photoshopped Photons".




Awesome post!

I've spent a lot of money on scopes, mounts, and eyepieces over the last two years and not one cent of it has included electronics*. What I have bought will never get passed on by new technology. In fact, I'll use it until I'm the one to pass on.

Nothing beats a simple walk through the woods, or through the stars for that matter. It's not a virtual experience I'm after.

*I do have SkySafari on an iPad, but that's not an integral or even necessary part of my viewing kit.


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JustaBoy
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Re: Time to ask the experts new [Re: karstenkoch]
      #6266208 - 12/21/13 11:56 PM

Bless you TechPan and Karsten!

You guys know what it's all about...


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Starman1
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Re: Time to ask the experts new [Re: faackanders2]
      #6266231 - 12/22/13 12:27 AM

Quote:

Quote:

True field in the 30mm ES will be 1.64 degrees. That's large enough for most large targets--not quite large enough to see ALL of the Pleiades or North America Nebula or California nebula or Veil nebula, etc., but certainly large enough for just about everything else. And large enough to see major portions of the really big things.

A note to consider, however, is that just about every object in the sky is a degree in diameter or smaller. Purchasing an eyepiece just for the 10-20 objects that are a bit larger seems like it would be a "supplemental" purchase for later, when filling in the "in-between" sizes and magnifications.
The 24mm x 82 ES would yield a true field of 1.28 degrees, which is still very large, and the magnification would be better for a much larger number of objects.




A 40mm 70 AFOV (or 41mm 68 AFOV Panoptic) would provided the widest TFOV for a 2"(48mm) barrell. I had this before I got a 30mm 82 AFOV and used it as my finder eyepiece, I may still be using it slightly more than the 30mm 82 AFOV for the large or multiple objects.



Sure, but you wouldn't use that in an f/4.9 dob. The exit pupil would be way too large and the secondary shadow might be obtrusive.


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Lorence
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Re: Time to ask the experts new [Re: Jeff Morgan]
      #6267100 - 12/22/13 03:23 PM

Quote:

More resolution is definitely needed, I have not looked at the Jr. I didn't realize that had gotten that cheap! I just spent $900 on a Leica ASPH this week.

Not to hijack the thread any further with this electronic eyepiece future stuff, but this time of year the idea of having the scope outside with me and display inside by the fireplace has some real appeal. Brrrrr.




The Mallincam Universe delivers a total size of 3032 X 2016. At that resolution one would be splitting hairs comparing the electronic view with visual. There are images made by the Universe on file at the Yahoo Mallincam site.

http://groups.yahoo.com/neo/groups/mallincam/info

-35 C and clear is the forecast for tonight. Not quite that cold in my armchair. A click on my observatory site will explain all.


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Ps191
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Re: Time to ask the experts new [Re: Lorence]
      #6319768 - 01/18/14 01:31 AM

Hi Everyone:

This is a long post but I want to give an update to this thread with a few observations from last night (Jan 16, 2014) using my (new to me) ES 24mm 82deg eyepiece for the first time. Before purchased this eyepiece I spoke with an ES rep on the phone and was impressed with their helpfulness and goal of customer satisfaction. They stand behind their products and – even when they are bought used. As you know I don't have much experience with higher quality, wideview eyepieces, so these thoughts are from a limited perspective and should be “taken with a grain of salt”.

I was using my 12” Orion dob (1500mm FL) which according to the spreedsheet from Starman1's “2013 Eyepiece Buyer's Guide” give a magnification of 63x and a true field of view of 1.31 deg.
I'm not sure how sky steadiness and transparency is defined but here's some thoughts. I've seen worse “twinkle” in stars during the winter at my location but then again I've seen steadier skies too, so lets call it low average of what I'd want to observe in. Late afternoon and early the next morning showed, scatterer high, thin clouds, possibly cirrostratus or leftovers from contrails but during the early part of the night when I observed the clouds where only at the far horizon. As you probably already guessed there was a lot of “light pollution” from the full moon, but this was the best night I've had in awhile and with a new eyepeice I used the opportunity I had. Comparisons where made with the Meade 25mm and no-name 1.125” eyepeieces mentioned in my first post. Telescope was collimate with my newly acquired Astronomics Cheshire/sight tube rather then the sight cap that came with the scope which I've used in the past and while I'm still learning the collimation thing, I believe I was close, if not, on. Temperature was in the low twenties and scope was precooled with box fan for about 30 minutes. Not sure if scope ever reached ambient temp because I could not see any hint of diffraction rings without fan blowing on back of scope and only glimpses of them in between what I assume was atmospheric turbulence. (telescope dons not have built in fans and I have not added any – yet).

Because of the less then ideal conditions I didn't spend a lot of time observing. The objects that got the time were, Sirius, Pleiades, Orion neb and the Moon. Sirius was used with a 9mm Meade eyepiece to check collimation, seeing (or lack thereof) and align the telrad. While the ES 24mm is large and my only experience with 2” eyepieces I did not have any trouble balancing it in my scope, in fact it was easier to balance then some of the lighter eyepieces. A side note is that this scope, even compared to a typical Orion, has less then ideal balance and movement (in both axis). I don't use glasses so eye positioning was easy to find and maintain with no noticed kidney bean. The field stop is seen easily enough when looking for it and I believe I could get close enough to see it all at once. While the field of view is wide and impressive I did not have the feeling that I was going to 'fall into' the view. Stars at the edge of the field show aberrations which I guess is coma since I don't use a coma corrector. While not to bothersome and almost ignorable (my perspective) it was noticed and will take father evaluation to decide if its expectable or if I'll need to start looking for a coma corrector.

The Orion nebula was beautiful and impressive. The trapezoid, with stars A through D, was clearly seen and possibly a glimpse of E through the less then idea seeing conditions. With the excess moon light, it seemed that I could see as much nebulosity in the Meade 25mm as the ES 24mm, although I would guess under darker skies the nebulosity would extend beyond the field of view shown in the Meade. The ES did a wonderful job framing the view and giving the perfect perspective and perspective is everything when it comes to enjoying the view. The view alone of the Orion neb made the price of admission worth it.

With the ES eyepiece the Pleiades cluster had a lot of stars in the field of view compared to either of the 1.25” format eyepiece. It began to have the open star cluster feel although it was missing the perspective seen in the Orion neb. And while good I'm still looking for that perfect, in between view of my previous eyepieces and my 10x50 binoculars. That said, I think there is enough there to see some nebulosity under darker skies. I look forward to revisiting this star cluster with ES 24mm and will not miss the 'soda straw view of two or three stars' seen with previous eyepieces. I'm guessing it will take a different telescope, like a 6” f5 refracter, to really make this eyepiece shine with the Pleiades. Oh well, I guess I need an excuse to dream about the iStar 6” f5

It took me but a couple of seconds viewing the moon to realize that while the wide field is nice for viewing the moon this not a lunar eyepiece and is best left to deepsky objects. On axis and close to the center the view was great but let the moon wonder close to the edge and it turned into a rainbow of color. Has anyone else notice this problem? I'll try again with a not so full moon and see what I think, but this eyepiece has not removed my long term goal of a quality set of lunar/planetary eyepieces.

Objects that I want to cover in the future include, Beehive, Andromeda galx, and a few other larger star clusters and galaxies. I would also like to check the color problem with Jupiter and revisit the few objects I viewed, especially the Orion neb. Overall I'm happy with my initial experience with the ES 24mm 82 deg. At this time I'm not planning to sell this eyepiece but look forward to many future nights of wonderful viewing. Now I can't wait to get my hands on a used copy of the ES 14mm 100 deg (or 82 deg) to enjoy a closer view of planetary neb's & globular clusters.

Thanks for all the advice and help Get out there and enjoy your astronomical observation


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herrointment
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Re: Time to ask the experts new [Re: Ps191]
      #6320463 - 01/18/14 12:59 PM

". On axis and close to the center the view was great but let the moon wonder close to the edge and it turned into a rainbow of color. Has anyone else notice this problem?"

I think everyone has!


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