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Extreme Makeover: Eyepiece Edition

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#1 Phillip Creed

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Posted 25 January 2013 - 12:41 PM

I've had a line-up of 82- and 100-deg eyepieces for a while, but I've finally decided to execute a plan that's been burrowing in the back of my head for some time.

My current line-up is:

30ES-82
23mm Axiom LX
13mm Ethos
9ES-100
2X GSO ED Barlow

I've decided that, as much as I love ultra- and hyper-wide angle eyepieces, I really, really, REALLY like long eye-relief. So I'm taking the unthinkable/heretical/blasphemous step of selling most of Nagler- and Ethos-class oculars and going to a long eye-relief, superwide (~70-deg AFOV) line-up for my core oculars. I'm keeping the 30ES-82; no issues there and I still maintain a "max" TFOV option, and changing the rest to:

30ES-82
22mm Vixen LVW
14mm Delos
10mm Delos
2X barlow
Option 1
Option 2

The 22mm LVW and the 10mm Delos are en route (thanks, Syed!) and I'll be looking for the 14mm Delos on the used market. I'm prepared to pay for a new 14mm Delos if necessary.

The issue is what to do below the 10mm Delos:

Option 1--Keep the 2X barlow and get a 7mm Pentax-XW.

Option 2--Keep the 2X barlow and get a 4X Powermate.

Advantages of Option 1--(1) I get a 7XW. 'Nuff said. (2) Eyepieces go down to 7mm without the use of any barlows, and I can get down to 3.5mm with the 2X barlow (286X on my 8" f/4.9 / 429X on my 12" f/4.9)

Advantages of Option 2--(1) I'm having a devil of a time finding a used 7XW, which would easily cost as much as the 4X Powermate, which I should be able to find more quickly on the used market (2) A 4X Powermate coupled with a 2X barlow maintains a 1.4X spacing from 14mm all the way down to 2.5mm (400X on my 8" f/4.9 / 600X on my 12" f/4.9), and if I really, really want to, can be stacked to get all the way down to 1.25mm, though I don't plan on going to South Florida anytime soon.

I'm vacillating between holding out for a 7XW, or just plowing ahead with the 4X Powermate.

Thoughts?

Clear Skies,
Phil

#2 MRNUTTY

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Posted 25 January 2013 - 01:58 PM

I'm with you on the 70 degree AFOV comfort. I bought my XW's for that reason. It also prompted me the get thee Delos EP for my main set. Looked for a PM4 for a couple of weeks, but nothing showed up so. I bought it new from eyepiecesetc.com. I have a 2x and a 4x Powermate to reach into the short FL's even though I have a lot of native short FL's. I find those high power EP's are hard to get a consistent clear picture at high mags. I would add more Delos as a third option.

#3 Dave M

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Posted 25 January 2013 - 02:17 PM

Ide go with Option 1.
Get the Pentax 7mm XW, i`m not a big fan of barlows myself, ide probably only ever barlow the 7mm to get 3.5mm on those rare occassions for planetary viewing.
Ive got an itch to look through your 10mm Delos :grin:
I dont know what you want to spend on a 7mm XW but you can get one new for $279 free shipping..

#4 Phillip Creed

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Posted 25 January 2013 - 04:38 PM

I would add more Delos as a third option.


But which one? The 10/8 spacing would be a bit close, but I prefer not to leave a gap between the 10D and the 6D, as that's the difference between 150X and 250X on my 12" dob.

I'd gladly add a third Delos if Televue made a 7mm Delos. But I guess they decided many buyers who have the 10mm Delos would forgo the decision between the 8mm and the 6mm Delos and just get both, so they're set up to sell more Deloses ("Deloi"?) than if they went from a 10mm straight to a 7mm.

Clear Skies,
Phil

#5 johnnyha

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Posted 25 January 2013 - 05:37 PM

I don't like the size of the 4X Powermate, especially coupled with long heavy eyepieces like the Delos. You are looking at nearly a foot of eyepiece sticking out of your focuser! The 7XW is a MUCH better option.

#6 Scanning4Comets

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Posted 25 January 2013 - 06:02 PM

I almost went the opposite route in getting all 82° and a couple of 100° eyepieces, but backed out at the last minute!

Kinda glad I did too because I have all close to 70° eyepieces with long eye relief. I have a 2" GSO barlow and I also use the barlow element on a 2" 35mm Blue Fireball extension tube for less mag, (named it my "black barlow"), which I use all of the time.

I will only screw the barlow element back onto the GSO 2" holder when I can crank the mag more.

Here is what I get with both barlow configurations: The only best scenario is with the 10mm and 7mm XW's giving me 210x, 240x, 300x & 350x when needed, as the rest are duplicated or close to it, so the only configurations that I use are in the black border.

If you're baffled at the mags and field sizes, I got these from drift timing the eyepieces several times ~ Just because the eyepieces say 10mm or 7mm or whatever, does not mean this is what they really are.

Phil: I think you should go with option #1 and get a 7mm XW!

Cheers,

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#7 Jeff Morgan

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Posted 25 January 2013 - 06:17 PM

Interesting line-up, you don't see many Denks about. How do like them vs. the Pentax?

#8 csrlice12

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Posted 25 January 2013 - 06:42 PM

Uh, 3, dig deep, buy both..... :yay:

#9 Starman81

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Posted 25 January 2013 - 08:17 PM

No problem, Phil! I hope you end up loving them. As for your choices, I would go with option 1 and pick up an XW 7 as soon as one becomes available on the used market. Until then, the 14 Delos barlowed will fill the spot very well, I am sure.

#10 MRNUTTY

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Posted 25 January 2013 - 08:29 PM

I would add more Delos as a third option.


But which one? The 10/8 spacing would be a bit close, but I prefer not to leave a gap between the 10D and the 6D, as that's the difference between 150X and 250X on my 12" dob.

I'd gladly add a third Delos if Televue made a 7mm Delos. But I guess they decided many buyers who have the 10mm Delos would forgo the decision between the 8mm and the 6mm Delos and just get both, so they're set up to sell more Deloses ("Deloi"?) than if they went from a 10mm straight to a 7mm.

Clear Skies,
Phil


Yeah... The Pentax stride is a little bit different than the Delos.
Pentax 14, 10, 7, 5, 3.5
Delos 14, 10, 8, 6, 4.5
Then Pentax goes at a faster slope. I selected the Delos 14, 10, 6 figuring if I didn't like the rate, I can get the 8 later. Or even the 4.5, but the EthosSX 4.7 covers that nicely. When I use the Pentax, I end up using them all. Since the 14 and 10 are common to both sets, you could crossover to the Pentax If you like that spacing, or go with the Delos. The Pentax is less expensive, but a wonderful EP. I really like them both. :-)

With respect to Barlow/Powermates, you either like them or not. The Powermate does preserve the ER of the EP, so if the shorter FL EP's ER (too many acronyms in a row alert!) if uncomfortable use the Powermate. Barlow's are useful too, but they have drawbacks. With them you can potentially double the number of available FL's you have to work with, if that's your goal; or you can spring for an EP for every FL you want to use.

#11 Phillip Creed

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Posted 26 January 2013 - 10:25 AM

I suppose another option might be:

Option 3--get a 7XW and exchange the 2X barlow for a 3X barlow. That makes a focal length line-up of 14, 10, 7, 4.7, 3.3 and 2.3mm, with the only break in the 1.4X spacing being the 1.5X spacing between the 7XW and the 3X-barlowed 14mm Delos. Exchanging a 2X for a 3X barlow is mostly cost-neutral.

I'm trying to keep the net transaction costs at a minimum. My wife's job security isn't great right now, so we're rushing to pay off our mortgage. We've paid off the majority of the principal and have good re-fi options if we're down to one income as is, BUT...every month we continue to divert extra funds towards it helps out all the more. So if I'm in the market for any new piece of equipment, it means selling an existing one to keep the costs down.

Much as I'd like to have a large Televue eyepiece Box O' Green Death, them dollars still have to be stretched right now. If the house is paid for and we've still got both our jobs, yes, then the eyepiece collection can grow. I've got a list a mile long of astro gear I'd at least consider buying once the siege finally lifts.

One thing I would to see in the future--ES? Televue? Hope you're listening--is splitting the difference eye-relief and AFOV-wise between the Delos and Ethos classes and making a 17/18-mm eye relief, 82-deg "Type 7"-Nagler class eyepiece. I'd be willing to bet ES could market something like that for less than the cost of the Delos line.

Clear Skies,
Phil

#12 russell23

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Posted 26 January 2013 - 10:58 AM

One thing I would to see in the future--ES? Televue? Hope you're listening--is splitting the difference eye-relief and AFOV-wise between the Delos and Ethos classes and making a 17/18-mm eye relief, 82-deg "Type 7"-Nagler class eyepiece. I'd be willing to bet ES could market something like that for less than the cost of the Delos line.

Clear Skies,
Phil


Phil I like your suggestion for a Nagler Type 7 line - but I'd like to see it be 85 deg AFOV. If they can get 15mm with the Ethos and 20mm of ER with the Delos, then they ought to be able to get 18mm with a Naglos line.

Dave

#13 Starman81

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Posted 26 January 2013 - 12:01 PM

Phil and Dave, perhaps you are forgetting the Type 4 Naglers? The 22mm has 19mm of ER and the 17/12 have 17mm. So no type 7 needed BUT they need to extend the Type 4's down to lower focal lengths perhaps.

But I would like ES to try their hand at a 70* AFOV 20mm ER eyepiece line, that's what I would like to see and I surprised they have not done it yet. Oh yes, and some Type 4 clones as well.

#14 Phillip Creed

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Posted 26 January 2013 - 12:08 PM

I did use the 17T4 in an f/5 refractor, and it looked absolutely fabulous, as there's no coma to correct for. The T4's work great in a fast reflector if--IF--you've got a Paracorr. They have noticeably more aberrations in fast Newts without a Paracorr vs. the T5's and T6's. I've tried all the T4's, and noticed this with my 12" f/4.9. I've also found them to be quite finicky when it comes to eye placement and I don't find them comfortable.

The T5's and T6's are more than sharp enough to use w/o a Paracorr at f/4.9. But the issue with the T6's is eye relief and the only T5's that have enough eye relief for me are the 26T5 and the 31T5, both wickedly expensive.

If I had a Paracorr, yes, I'd probably go for the 17T4 and the 12T4 and simply learn how to position my eye. But since I don't have one (and don't really plan on getting one), I'd rather not incur the extra cost.

Clear Skies,
Phil

#15 Scanning4Comets

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Posted 26 January 2013 - 02:54 PM

Yup to above. However, I still have a fond place for the 12mm T4: I learned how to use it and wouldn't hesitate to get another! I sent you a PM about a 7mm Pentax XW Steve, not mine, but another I found. Mine will be gripped in my hands forever.


Interesting line-up, you don't see many Denks about. How do like them vs. the Pentax?


If you're talking as compared to a 14mm XW, the 14mm Denk is better edge wise as there is very, very minimal FC compared to the 14mm XW. Transmission wise, etc, I would need a lot more time going back and forth between the 14mm Denk and the 14mm XW, which can be done soon as a good friend of mine, (Junomike), has the 14mm XW. I almost sold the 14mm Denk a few times because I wanted to try something new. I'm kinda glad I didn't because I can get it out to darker skies when this cold snap subsides and do a shoot out between it and the 14mm XW, and seeing as there is no eyepiece in this FL size @ 70­°, I'd more than likely just keep it. FYI, the 14mm Denk works as a 15.7mm EP in my scope @ 76x.

That will be a really neat shoot-out for sure!

Cheers,

#16 kkokkolis

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Posted 26 January 2013 - 05:02 PM

I would go for Delos 6mm and in fact that's what I did. A great option for a 12" f/5. 250mm is the highest possible magnification most of the nights (at least where I live). And 500x with a Barlow is more than enough.
If that 22mm LVW wasn't en route I'd suggest to give a try to ES68 24mm.

#17 russell23

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Posted 26 January 2013 - 07:55 PM

Phil and Dave, perhaps you are forgetting the Type 4 Naglers? The 22mm has 19mm of ER and the 17/12 have 17mm. So no type 7 needed BUT they need to extend the Type 4's down to lower focal lengths perhaps.


I tried a 17mm T4 Nagler. It was decent but I ended up liking the 20mm XW more.

However, the point is that the Ethos and Delos are supposed to be the pinnacle of TV eyepiece design. The Delos applies lessons they learned to a 72 deg AFOV line. So it ought to be possible to apply the lessons to an 85 deg AFOV line.

If the T4 line could be extended to shorter FL it would have been. And it is not without it's issues - The 17mm and 22mm T4's are 1.5 lbs or more in weight. The 12mm T4 has frequently reported issues with blackouts. In my experience the Delos has much less issue with blackouts than the T4 Nagler.

So why not update the Nagler line? TV could keep the 26mm and 31mm T5 Naglers and replace the T4, T5, and T6 Naglers with 3.5mm to 21mm FL Naglers that have 17mm-18mm of eye relief and are based upon design parameters first implemented with the Ethos line.

But I would like ES to try their hand at a 70* AFOV 20mm ER eyepiece line, that's what I would like to see and I surprised they have not done it yet. Oh yes, and some Type 4 clones as well.


If ES comes out with an advanced 70mm AFOV line I suspect it will take some time. It seems that they have reached somewhat of a limit in releasing new products. The 5.5mm ES100 has been listed as pre-order from ES for almost 2 years now and there is no public information from the company as to whether or not and when it might actually appear.

Dave

#18 GeneT

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Posted 26 January 2013 - 08:12 PM

Option 1--Keep the 2X barlow and get a 7mm Pentax-XW.


I am sure that the 7mm XW is a great eyepiece. So are the 8 and 6mm Delos. I own both and am extremely pleased with them.

#19 Stephen S

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Posted 03 February 2013 - 05:52 PM

I've tried various configurations of eyepieces and scopes. The 7mm XW is the one eyepiece I find that seems to work well with everything I've tried. I ended up getting the entire collection of 1.25" XWs as a result. I've also got the Nagler T4s (I too like long eye relief). Still, the 7mm XW is my favorite.

I'm a huge Televue fan. I tried the 8mm Delos. Great eyepiece but no better to my eyes than the XW. For some reason, I found the Pentax easier to use (familiarity I guess). I don't think you can go wrong getting the 7mm XW. Even if you have to buy new (can be found for $280 delivered), they old their value enough that you could sell it later for nearly what you paid new. That said, the 7mm XW is the one eyepiece in my line-up that I can't see myself ever selling. I know I would miss it immediately.

My two cents. Best of luck as you work towards your realignment.

Steve S

#20 GeneT

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Posted 03 February 2013 - 06:12 PM

Here's how I sorted out my situation for a 12.5 inch, F5 Dob:
31, 22 Naglers; 14, 10, 8, 6 Delos; 5 Pentax XO; 4 Radian; 2X Powermate. This is a minimalist set that covers all the bases.

#21 Phillip Creed

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Posted 09 February 2013 - 03:07 PM

I just pulled the trigger on a 14mm Delos. I figured it would be a while before I found a used one, so I just bit the bullet and ordered a new one.

I've sent out the 23mm Axiom LX, the 13mm Ethos and the 9ES-100. So now, my line-up is:

30ES-82
22mm LVW
14mm Delos
10mm Delos
2X Barlow.

I'm still torn between the 4X Powermate and the 7XW. I had to get the 14mm Delos new, and I don't like paying retail prices (though I got it at the cheapest vendor I could find) and I really, really hate debt of all kinds, and especially using credit cards. I'd rather feel the "pain" of paying in full once and being done with it.

The 4X Powermate is something that I can at least find used, and thus pay with check/money order. Apparently everyone out there who'd be in the position to sell a used 7XW is treating it as one of their "cold, dead hands" kind of eyepieces (and I suppose for very good reason) and has them under lock and key deep underground at a facility surrounded by fuming moats of 18-molar sulfuric acid, complete with a security perimeter of motion-activated .50-cal machine guns. Hey, it's a good eyepiece, what more can you say?

Clear Skies,
Phil

#22 Phillip Creed

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Posted 09 February 2013 - 03:15 PM

Let's see...lock-and-key, fuming sulfuric acid, .50-cal machine guns...oh, yeah--ninjas. Don't forget about the ninjas.

Clear Skies,
Phil

#23 Scanning4Comets

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Posted 09 February 2013 - 03:26 PM

Nice line up Phil! :bow:

I had thought about the 30mm ES myself, but still haven't found one...so I guess I may just wait. I grabbed another 38mm Orion Q70 for a finder eyepiece and also for The Veil.

How exactly is the 30mm w/o a Paracorr? I am very curious about that eyepiece and the correction / weight issues.

I still have my 10mm and 7mm XW's! Hmmmmm.....If I didn't get the 38mm Q70, I could have traded you my 7mm XW for your 30mm ES, LOL!

I never thought about that until now.....but I guess your 30mm ES is glued to your hands with the .50 cal guns and surrounding Ninjas hahaha!

Cheers,

#24 junomike

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Posted 09 February 2013 - 04:04 PM

What purpose is the 4X PowerMate going to serve? If you use the 14mm Delos + 2X Barlow, you'll get the 7mm F/L.
Then when you finally do find that 7mm XW, the 2X Barlow can go. Or am I missing something?

Mike

#25 Phillip Creed

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Posted 09 February 2013 - 04:10 PM

I'd recommend the 30ES-82 over the 31T5 unless you really, really, must have the 31T5 and nothing else will do. The cost differential is signficant, while the gap in performance is slight. It handles off-axis astigmatism very well in my f/4.9 scopes w/o a Paracorr. You will see coma, but that's from the mirror.

I have the new 2.4-lb. N2-purged version, and at one point I had the older, 3.1-lb. (!!) version of it, though from what I can tell, the optics are the same. The newer commercial 8"-16" dobs have tension-control adjustments on them that are more than adequate to prevent the UTA from tipping.

I popped the 30ES-82 into two f/5 refractors, a 120ST and a 150mm f/5 Celestron Omni, to test it in a fast scope and do a test that removes the effect of coma. It was very sharp right to the edge, and the view of the Veil Nebula (as in all of it) in the 150 f/5 is one I'll long remember.

The only thing I could see that prevented it from being perfect was a tiny bit of field curvature in the 120ST, and less so in the 150 f/5, but not much. It had signficantly less field curvature than a 14mm XW or 14ES-82; it simply isn't an issue with the 30ES-82, and my eyes are pretty sensitive to FC.

In no way would I spend the extra $400 to get the 31T5. And yes, I've looked through The Terminagler. Nothing against it. But IMO, the 30ES-82 is just way too close in performance to justify throwing in an extra car payment on top of the 30ES-82 just to get the 31T5.

Clear Skies,
Phil






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