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Building out a Tele Vue & Powermate EP set

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#1 Chirpy73

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Posted 29 May 2024 - 02:30 PM

I'm in the UK and quite new to astronomy and am visual/observing only.  I bought a Celestron Nexstar 6SE around 6 months ago.  (f/10, FL 1500mm)

 

I initially compiled a set of 7 eyepieces, mixed between new, supplied, & 2nd hand purchases.  This range comprised of: -

  • Celestron X-CEL LX in; 7mm (x214), 9mm (x167), 12mm (x125), 18mm (x83)
  • BST Starguider ED 15mm (x100)
  • Supplied Celestron 25mm Plossl (x60)
  • Meade 4000 Super Plossl 32mm (x47) 

This is obviously a full set of eyepieces, and I understand that an f/10 scope is particularly undemanding on EP's. So logic suggests all is well in the world, and I should stop right here.

 

...However, I decided to replace the supplied Plossl, and having spent far too much time on CN, started to explore Tele Vue.  This led to a return to the 2nd user market, and a quick fire succession of purchases;

  • Tele Vue Plossl 32mm (x47)
  • Tele Vue Panoptic 24mm (x63)
  • Tele Vue Panoptic 19mm (x79)

Clearly these now displace the supplied 25mm Plossl, the Meade 32mm Plossl (bad buy that anyway I think? - its the Chinese version) and also the XCEL LX 18mm. 

 

I'm in no rush to move on the displaced EP's, but am considering what my next moves should be in the medium to higher power FL ranges.

 

My 'draft plan is to add a x2.5 Powermate to the two Panoptics I now own, which will give me:

  • 24mm = 9.6mm / x156
  • 19mm = 7.6mm / x197

Then later replace my 15mm BST StarGuider with either a TV Delite 15mm (or possibly TV Delos 14mm).  Delite would give me x100 and with the Powermate, 15mm = 6mm / x250 (for that one UK clear seeing day a year!)

 

The end game therefore would look like: -

  • TV Plossl 32mm = x47
  • TV Panoptic 24mm = x63
  • TV Panoptic 19mm = x79
  • TV Delite 15mm = x100
  • TV Pan + PM = x156
  • TV Pan + PM - x197
  • TV Delite + PM = x250

- I would then head out with a case of just 4 x EP's & one Powermate

- The AFOVs (excluding Plossl) are all between 62 - 68 degrees. (so no huge divergence/disparity when moving up and down powers).

- I'd have a heap of Celestron, BST & Meade EP's to sell off!

- I do have the f6.3 focal reducer too, so can also get slightly wider fields on the lower power EPs, without starting to get complex with 2" EP's - that's not for this scope, IMHO.

 

My main concerns are the use/wisdom of bringing in the Powermate, the range of magnifications I will have and if any are unwise/too close, if I still have too many EP's, and any other unknowns I may not have been aware of due to my inexperience.

 

Thanks in advance for any comments!
Jon

 

(Nb I fully anticipate Don Pensack saying scrap the whole plan and buy the entire TV Ethos range instead!) grin.gif


Edited by Chirpy73, 29 May 2024 - 02:31 PM.


#2 William Lewis

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Posted 29 May 2024 - 03:20 PM

Hi Chirpy73

I have the 2.5x powermate and cant recommend it highly enough. I used to use a 2x Barlow but find the powermate much better, you just don't know it's there except for the extra magnification. I'm by no means an expert but I know I'm happy with it!
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#3 Jethro7

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Posted 29 May 2024 - 03:44 PM

Hello Jon 

Eyepieces choices are personal thing. With that being said,  I am very pleased with my Tele Vue eyepiece line up and second the Powermate. 

 

HAPPY SKIES AND KEEP LOOKING UP Jethro

 

P. S. If  Don, chimes in. He will more than likely advise you to stay with the 1.25" eyepieces because the C6 was designed with a 1.25" format and you won't benefit from 2" eyepieces and diagonals.


Edited by Jethro7, 29 May 2024 - 03:51 PM.

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#4 AstroApe

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Posted 29 May 2024 - 04:25 PM

Your endgame line looks solid with a good range of magnifications. I prefer fixed length eyepieces due to less weight & height in the focuser, but high quality Barlows and focal extenders like the Powermate work very well and almost disappear in the lightpath. 

 

To be honest, I doubt you'd use the 32 Plössl very much unless trying to get a larger exit pupil than the 24 Pan would give. The TFOV is very close between the two (32 = 1.07° vs 24 = 1.09°), but the wider AFOV & darker background of the Pan will give it the edge IMO. Both eyepieces offer the near maximum FOV in a 1.25" eyepiece. The Plössl is a great eyepiece tho and one I'd advise holding on to since you've already got it.

 

The Delites are great eyepieces. I love the Delos series, they're perhaps my favorite eyepieces and match up great with Panoptics, but are quite a bit bigger than the Delites and they're quite a bit more expensive. The views are very similar through both (excellent!), just different FOVs (62° vs 72°).

 

BTW, if you've got a rather large sum of money to burn through for some high quality astro gear, Don might just recommend a full set of Ethos... but luckily he's also great at recommending eyepieces for just about every budget and scope an amateur astronomer would likely come across, so I doubt he'd recommend that lol.gif He's extremely knowledgeable and a very respected member in this world of Amateur Astronomy however, so you'd do wise to put some weight behind his advice and recommendations IMHO. 

 

EDIT: forgot to mention, welcome to the awesomeness of CloudyNight's!! :welcome:


Edited by AstroApe, 29 May 2024 - 04:32 PM.

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#5 f74265a

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Posted 29 May 2024 - 04:46 PM

That’s a very nice 5 piece set. 2.5 pm is a wonder.
My only thought is that you might consider substituting the 18,2 delite for your 19 pan. The 18.2 is one of TV’s best offerings. On the other hand, Of the several dozen TV eyepieces that i have, the 19 pan is far from a favorite. I bought it after loving the 24 pan but regret the purchase. Perhaps personal preference. See how you get along with the very good 15 delite before making any decisions though.
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#6 SeattleScott

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Posted 29 May 2024 - 05:00 PM

Hmm. See below. Look up the Celestron Xcel LX series.

http://astro-talks.r...opic.php?t=1483

So the two Xcel LX eyepieces that you intend to replace with the Powermate are the stars of the series, both getting excellent scores and essentially perfect at F10. As a matter of fact, if you scroll down to the Panoptics, you will see that none of them quite got the coveted yellow highlight. Granted the 19 wasn’t tested. Of course with the Powermate the Panoptics would have better edge correction, but the truth is, you could easily use the Xcel LX or Panoptics at F4. At F10 they will both be basically perfect. So you are upgrading from 60 AFOV to 68 AFOV. The 7Xcel LX is actually 62 AFOV. With the 24 Panoptic, it is 65 AFOV and replacing a 59 AFOV. So we are really just talking about a 10% increase in AFOV. Do you want to mess with a barlow just to get a 10% wider view?

The 15 Starguider isn’t that well known. The 12 Xcel LX is fine but not a standout. I could see a 13 Nagler or something. I’m not sure about Delite as you are only upgrading from 60 to 62 AFOV, and it is way more expensive. Even against mediocre eyepieces, it could be hard to tell a difference at F10. I would hate for you to spend $300 and feel like you can’t tell a difference. At least with the Nagler, you could tell a difference. Like 30% wider.

So yeah I would look more at a 13 Nagler, or at least a 14 Delos to get a wider view. If you are going to spend this kind of money, you want to be able to see a noticeable difference, not squinting and trying to convince yourself that the Delite is better than the others.

Below that, I would just stick with the Xcel LX unless you want to go ultrawide. 9 and 7 Nagler would work. Obviously more expensive than a Powermate. But I just don’t think I would want to bother messing with a barlow just to get 65 instead of 59 AFOV, or 68 instead of 62. Not worth the hassle. Panoptics are nice, but they aren’t magical. I just really question if you would see any difference other than a minor AFOV difference, unless there is something wrong with your Xcel LXs (dust/dirt inside, etc.).
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#7 SeattleScott

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Posted 29 May 2024 - 05:10 PM

Just fyi your Xcel 7 is really 6.5mm.

For an obstructed scope, especially a SCT, I think of 40x per inch as a realistic max magnification. So 240x or so. The 7 Xcel LX gets you to 230x. Probably close enough. Yes, a 15 Delite plus 2.5x Powermate would get you all the way to 250x.

Now if you want to use the reducer, it is kind of a pain to be swapping on and off during an observing session. You might just want to leave it on for high power viewing. In that case you might want the Powermate paired with a 10mm eyepiece or something. The Powermate with the 9Xcel LX would hit about 260x. So might not want to sell off everything below 15mm too fast.

Edited by SeattleScott, 29 May 2024 - 05:15 PM.

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#8 SeattleScott

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Posted 29 May 2024 - 05:21 PM

What diagonal are you using? I believe the stock diagonal with a 6SE is a 1.25” prism diagonal. Based on online images, I would not buy a 2.5x Powermate to go in a 1.25” prism diagonal. At least not unless I wanted an excuse to replace the diagonal. I mean, there’s always the “oops I broke it” excuse to justify an equipment upgrade. If that’s the goal, then by all means get the Powermate.

To clarify, there are different barrel styles online. If the image on the TV website is current, it should work fine with a 1.25” prism. It won’t insert all the way, but it won’t damage the prism, and you aren’t looking at barlowing monster eyepieces so it should still be stable enough despite sticking out a bit.

Edited by SeattleScott, 29 May 2024 - 05:42 PM.

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#9 25585

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Posted 29 May 2024 - 06:17 PM

I really like my 4x Powermate. TV actually says it makes a great 8mm with a 35mm Panoptic. I use mine with my big eyepieces (no TV), fabulous optics.


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#10 Chirpy73

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Posted 30 May 2024 - 02:58 PM

Hi Chirpy73

I have the 2.5x powermate and cant recommend it highly enough. I used to use a 2x Barlow but find the powermate much better, you just don't know it's there except for the extra magnification. I'm by no means an expert but I know I'm happy with it!

Thanks William, that sounds a +1 to the PowerMate plan then!



#11 Chirpy73

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Posted 30 May 2024 - 03:24 PM

Hello Jon 

Eyepieces choices are personal thing. With that being said,  I am very pleased with my Tele Vue eyepiece line up and second the Powermate. 

 

HAPPY SKIES AND KEEP LOOKING UP Jethro

 

P. S. If  Don, chimes in. He will more than likely advise you to stay with the 1.25" eyepieces because the C6 was designed with a 1.25" format and you won't benefit from 2" eyepieces and diagonals.

Cheers Jethro, +2 for the Powermate! 

 

Re: 2" EP's - I did read a good few threads with some 'robust' debates around the use of a 2" diagonal & EP's on a Nexstar 6SE.  Whilst many people vouched of its success for them, there was a strong case made for physical limitations of the 'baffle' (?), and a really good point about f/10 SCTs being good versatile jack's of all trades, but not a master of wide field - and if you really want wide field as well, I think it was Don who suggested to buy a 2nd companion scope which is fit for that purpose!

 

Also, one of my main buying criteria for a go-to scope of 6" size, was that I need a portable 'grab and go' which can be easily moved into the boot (sorry, trunk ;-D ) of my car, then packed away neatly when back home. Adding 2" EP's etc would add size & weight - so I drew the line at 1.25"



#12 Chirpy73

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Posted 30 May 2024 - 03:35 PM

Your endgame line looks solid with a good range of magnifications. I prefer fixed length eyepieces due to less weight & height in the focuser, but high quality Barlows and focal extenders like the Powermate work very well and almost disappear in the lightpath. 

 

To be honest, I doubt you'd use the 32 Plössl very much unless trying to get a larger exit pupil than the 24 Pan would give. The TFOV is very close between the two (32 = 1.07° vs 24 = 1.09°), but the wider AFOV & darker background of the Pan will give it the edge IMO. Both eyepieces offer the near maximum FOV in a 1.25" eyepiece. The Plössl is a great eyepiece tho and one I'd advise holding on to since you've already got it.

 

The Delites are great eyepieces. I love the Delos series, they're perhaps my favorite eyepieces and match up great with Panoptics, but are quite a bit bigger than the Delites and they're quite a bit more expensive. The views are very similar through both (excellent!), just different FOVs (62° vs 72°).

 

BTW, if you've got a rather large sum of money to burn through for some high quality astro gear, Don might just recommend a full set of Ethos... but luckily he's also great at recommending eyepieces for just about every budget and scope an amateur astronomer would likely come across, so I doubt he'd recommend that lol.gif He's extremely knowledgeable and a very respected member in this world of Amateur Astronomy however, so you'd do wise to put some weight behind his advice and recommendations IMHO. 

 

EDIT: forgot to mention, welcome to the awesomeness of CloudyNight's!! welcome.gif

Thanks for the welcome - glad to be here!  I did spend 6 months in 'lurker' mode, ensuring I had fully read and digested the entire back catalogue of CN threads first, prior to plucking up the courage to actually post here!  lol.gif

 

Thanks for the comments too.  I did release when I added the 32mm Plossl that I probably didn't 'really' need it - I've started my own spreadsheet+formulas to quickly calculate and compare EP's, magnifications, AFOV, TFOV, price etc, so had spotted the 32mm & 24mm were effectively both at the max TFOV you can get on a 6SE...  

 

However, 2 weeks after picking up the 24mm Panoptic, the 32mm Plossl came onto the UK facebook site and I got it for £80.  (my decision making process was made easier by a generous quantity of beer consumed earlier that Sunday afternoon!...) grin.gif

 

A similar fate occurred a week later with the 19mm Panoptic, when one was on offer for £135, so again, I just dived in and brought it into the kit bag.  

 

Collecting EP's is proving somewhat addictive.. its lucky I'm limited on space for scopes really!


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#13 Chirpy73

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Posted 30 May 2024 - 03:36 PM

I really like my 4x Powermate. TV actually says it makes a great 8mm with a 35mm Panoptic. I use mine with my big eyepieces (no TV), fabulous optics.

Brilliant, thanks 25585 - lots of love for the Powermates so far, that's 4 yes votes!


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#14 Chirpy73

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Posted 30 May 2024 - 03:49 PM

Hmm. See below. Look up the Celestron Xcel LX series.

http://astro-talks.r...opic.php?t=1483

So the two Xcel LX eyepieces that you intend to replace with the Powermate are the stars of the series, both getting excellent scores and essentially perfect at F10. As a matter of fact, if you scroll down to the Panoptics, you will see that none of them quite got the coveted yellow highlight. Granted the 19 wasn’t tested. Of course with the Powermate the Panoptics would have better edge correction, but the truth is, you could easily use the Xcel LX or Panoptics at F4. At F10 they will both be basically perfect. So you are upgrading from 60 AFOV to 68 AFOV. The 7Xcel LX is actually 62 AFOV. With the 24 Panoptic, it is 65 AFOV and replacing a 59 AFOV. So we are really just talking about a 10% increase in AFOV. Do you want to mess with a barlow just to get a 10% wider view?

The 15 Starguider isn’t that well known. The 12 Xcel LX is fine but not a standout. I could see a 13 Nagler or something. I’m not sure about Delite as you are only upgrading from 60 to 62 AFOV, and it is way more expensive. Even against mediocre eyepieces, it could be hard to tell a difference at F10. I would hate for you to spend $300 and feel like you can’t tell a difference. At least with the Nagler, you could tell a difference. Like 30% wider.

So yeah I would look more at a 13 Nagler, or at least a 14 Delos to get a wider view. If you are going to spend this kind of money, you want to be able to see a noticeable difference, not squinting and trying to convince yourself that the Delite is better than the others.

Below that, I would just stick with the Xcel LX unless you want to go ultrawide. 9 and 7 Nagler would work. Obviously more expensive than a Powermate. But I just don’t think I would want to bother messing with a barlow just to get 65 instead of 59 AFOV, or 68 instead of 62. Not worth the hassle. Panoptics are nice, but they aren’t magical. I just really question if you would see any difference other than a minor AFOV difference, unless there is something wrong with your Xcel LXs (dust/dirt inside, etc.).

Hey Scott, thanks for this - that is superb feedback and I appreciate the link.  I really like the idea of elongating the tenure of the XCEL LX's.  Certainly the 7mm & 9mm were bought new, and the 12mm & 18mm were obtained after for a low UK£45 2nd hand, so no big deal there.  Great they are so highly rated.  This gives me plenty of time to attend some more dark sky events, and trial some Delos's, Delite's and Naglers (slightly wary of the shorter eye relief, although I don't wear glasses, but would be good to try before I buy)

 

I did note the 7mm was actually 6.5mm too, which is good.  I believe I saw on CN somewhere that they were anatomically the same as a Meade range, which did use x.5mm delineations, and Celestron wanted to differentiate so just rounded up and down their focal lengths to the nearest full mm!

 

On the link you sent me, I translated back to English of course, but didn't see an explanation around why the AFOV's quoted differed from the vendor specifications - quite dramatically in some EP's and even through the range.  I'm assuming this is a result of independent and verified testing etc?

 

You asked in a later post about what diagonal I'm using.  I swapped the stock one out for the Celestron Dialectic: https://www.celestro...61dfe36fc&_ss=r

 

Were you saying the TV Powermate is known to break the diagonal then?

 

Thanks! :-) 

 

 

Edit:  Just realised, the BST Starguider goes by different names globally.  I *believe* it might be known as an Astro Tech Paradigm Dual ED in the US.


Edited by Chirpy73, 30 May 2024 - 03:51 PM.


#15 Chirpy73

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Posted 30 May 2024 - 03:55 PM

That’s a very nice 5 piece set. 2.5 pm is a wonder.
My only thought is that you might consider substituting the 18,2 delite for your 19 pan. The 18.2 is one of TV’s best offerings. On the other hand, Of the several dozen TV eyepieces that i have, the 19 pan is far from a favorite. I bought it after loving the 24 pan but regret the purchase. Perhaps personal preference. See how you get along with the very good 15 delite before making any decisions though.

Thank you - that's 5 thumbs up for Powermates!

 

I'll add the 18.2mm to the options/trial list.  I only acquired the 19mm Pan a couple of weeks ago, so haven't given it a run yet.  It only cost me £130 though, so if I don't like it, I can easily flip it at no loss - that seems to the be the joy of the TV 2nd hand market.

 

What was it you didn't like about the 19mm btw? 



#16 SeattleScott

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Posted 30 May 2024 - 05:39 PM

Hey Scott, thanks for this - that is superb feedback and I appreciate the link. I really like the idea of elongating the tenure of the XCEL LX's. Certainly the 7mm & 9mm were bought new, and the 12mm & 18mm were obtained after for a low UK£45 2nd hand, so no big deal there. Great they are so highly rated. This gives me plenty of time to attend some more dark sky events, and trial some Delos's, Delite's and Naglers (slightly wary of the shorter eye relief, although I don't wear glasses, but would be good to try before I buy)

I did note the 7mm was actually 6.5mm too, which is good. I believe I saw on CN somewhere that they were anatomically the same as a Meade range, which did use x.5mm delineations, and Celestron wanted to differentiate so just rounded up and down their focal lengths to the nearest full mm!

On the link you sent me, I translated back to English of course, but didn't see an explanation around why the AFOV's quoted differed from the vendor specifications - quite dramatically in some EP's and even through the range. I'm assuming this is a result of independent and verified testing etc?

You asked in a later post about what diagonal I'm using. I swapped the stock one out for the Celestron Dialectic: https://www.celestro...61dfe36fc&_ss=r

Were you saying the TV Powermate is known to break the diagonal then?

Thanks! :-)


Edit: Just realised, the BST Starguider goes by different names globally. I *believe* it might be known as an Astro Tech Paradigm Dual ED in the US.

You will be fine with a mirror diagonal. There is a body style of the 2.5x Powermate (probably older style) that looks downright dangerous for a 1.25” prism. But no problem for a mirror. It will stick out a ways though, which might be a concern if you put tall, heavy eyepieces in it.

The Powermate won’t hurt the image. I have a TV barlow and it is likewise excellent. The real issue is whether it is worth the effort to mess with it in order to get an extra six degrees of AFOV. Especially if you feel like it isn’t especially stable because it won’t seat all the way. Think of it less as a performance issue and more of a convenience issue. If your 9/7 weren’t so highly rated, there might be a performance gain barlowing the Panoptics. I’m guessing you won’t really see a performance gain other than 10% more AFOV. I could be wrong. Now if you like using the reducer, that could create a need for a barlow or Powermate. Honestly though I still wouldn’t be crazy about the 2.5x Powermate in a 1.25” diagonal. Maybe a top rated Nikon 1.6x? That would give 233x using the 7Xcel LX with reducer in place, versus 230x without reducer or barlow. Basically it would offset the reducer. It is a nice, small barlow that will seat in a 1.25” diagonal nicely, and gets outstanding reviews.

Yes Ernest measures the AFOV and it often varies from advertised amount. I’m not sure exactly what his process is, and I wouldn’t accept his numbers as Gospel. But overall they are probably more accurate than the advertised amounts.
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#17 SeattleScott

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Posted 30 May 2024 - 05:44 PM

BTW the Nikon 1.6x with your Panoptics would yield 15mm and 11.9mm. Nicely filling the gap to 9mm. And you could also use it with the reducer, as your eyepieces would provide basically the same magnification with the reducer and barlow as without reducer and barlow.
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#18 Jethro7

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Posted 30 May 2024 - 07:29 PM

Cheers Jethro, +2 for the Powermate! 

 

Re: 2" EP's - I did read a good few threads with some 'robust' debates around the use of a 2" diagonal & EP's on a Nexstar 6SE.  Whilst many people vouched of its success for them, there was a strong case made for physical limitations of the 'baffle' (?), and a really good point about f/10 SCTs being good versatile jack's of all trades, but not a master of wide field - and if you really want wide field as well, I think it was Don who suggested to buy a 2nd companion scope which is fit for that purpose!

 

If you look into the Corrector plate of your C6 towards the primary mirror, you will see a tube in the center of the primary mirror, this is the baffle and it is narrow and this is why 2" eyepieces are not optimal for a C6. 2" eyepieces will still work on the C6 but just not optimally.  My C8 Edge HD scope has a much wider baffle to accommodate the 2" Format.

 

Most of us that have been at the Astro Hobby for any length of time own more than one scope and these different scopes perform  different jobs or give a different viewing experience. With that being said, if you were to pick up say an 80mm to 100mm F/5 ish type refractor. This would give you those cherished low power wide field views of starfieldes and you will more than likely be able to use it on the Celestron Se Mount provided that the scope is not too long on the focuser end and the diagonal will clear the base when viewing towards the Zenith. The mount does not know what scope is mounted in the saddle.

 

The Orion ST 80 is a good obe or maybe a Skywatcher Startravel 80mm or 102mm F4.9  would be a good choice and can be found used quite often for a good price.

 

https://www.teleskop...-80-400-mm-3553

 

https://www.teleskop...-102-500mm-2685

 

 

Also, one of my main buying criteria for a go-to scope of 6" size, was that I need a portable 'grab and go' which can be easily moved into the boot (sorry, trunk ;-D ) of my car, then packed away neatly when back home. Adding 2" EP's etc would add size & weight - so I drew the line at 1.25" 

This is your show and you are writing the script and what ever works for you is good. But the folks here on CN, are always willing to to help you.

 

HAPPY SKIES TO YOU AND KEEP LOOKING UP Jethro

 


Edited by Jethro7, 30 May 2024 - 08:00 PM.

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#19 Chirpy73

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Posted 31 May 2024 - 09:02 AM

You will be fine with a mirror diagonal. There is a body style of the 2.5x Powermate (probably older style) that looks downright dangerous for a 1.25” prism. But no problem for a mirror. It will stick out a ways though, which might be a concern if you put tall, heavy eyepieces in it.

The Powermate won’t hurt the image. I have a TV barlow and it is likewise excellent. The real issue is whether it is worth the effort to mess with it in order to get an extra six degrees of AFOV. Especially if you feel like it isn’t especially stable because it won’t seat all the way. Think of it less as a performance issue and more of a convenience issue. If your 9/7 weren’t so highly rated, there might be a performance gain barlowing the Panoptics. I’m guessing you won’t really see a performance gain other than 10% more AFOV. I could be wrong. Now if you like using the reducer, that could create a need for a barlow or Powermate. Honestly though I still wouldn’t be crazy about the 2.5x Powermate in a 1.25” diagonal. Maybe a top rated Nikon 1.6x? That would give 233x using the 7Xcel LX with reducer in place, versus 230x without reducer or barlow. Basically it would offset the reducer. It is a nice, small barlow that will seat in a 1.25” diagonal nicely, and gets outstanding reviews.

Yes Ernest measures the AFOV and it often varies from advertised amount. I’m not sure exactly what his process is, and I wouldn’t accept his numbers as Gospel. But overall they are probably more accurate than the advertised amounts.

Terrific, thanks one again Scott.  I'm committed to only using 1.25" on this scope, so hopefully weight won't be an issue.

 

But, to be honest you've really opened my eyes to the value of the 7mm (aka 6.5mm) & 9mm I already own, and the feedback you gave was top drawer around the minimal perceptible difference I'd gain on TFOV if I was to Powermate/Barlow up my Panoptics.  Based on that, I have a renewed confidence & vigour to use the heck out of the options I have now!

 

In future, if a 2.5x Powermate comes up on the 2nd-user market, I might take it, purely as something to play around with (it'll likely hold its value anyway) and to educate myself on the FOV changes.  In the short-medium term though, I'm 'sticking' rather than 'twisting' - thank you Scott!



#20 Chirpy73

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Posted 31 May 2024 - 09:05 AM

BTW the Nikon 1.6x with your Panoptics would yield 15mm and 11.9mm. Nicely filling the gap to 9mm. And you could also use it with the reducer, as your eyepieces would provide basically the same magnification with the reducer and barlow as without reducer and barlow.

You can probably hear the cogs in my brain whirring from Seattle as I work out the combinations! lol.gif

 

Interesting - I'll plug it into my excel sheet and model out some scenarios, thanks!

 

Nikon do not seem to be very visible over here in the UK, so it wasn't on my initial radar.



#21 Chirpy73

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Posted 31 May 2024 - 09:06 AM

 

Thanks Jethro, and you have indeed all been a great help (on this my first thread, and also all the legacy threads I've been consuming this year!). bow.gif


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#22 SeattleScott

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Posted 31 May 2024 - 09:50 AM

You can probably hear the cogs in my brain whirring from Seattle as I work out the combinations! lol.gif

 

Interesting - I'll plug it into my excel sheet and model out some scenarios, thanks!

 

Nikon do not seem to be very visible over here in the UK, so it wasn't on my initial radar.

You can purchase direct from Japan, but you would probably have to buy a couple things to meet price threshold for an international transaction. The EiC is 18k yen. Need to hit 50k. Pentax XWs are a very good price, the 20-5 are under 30k yen. But if you are buying a barlow in lieu of buying eyepieces, it kind of defeats the purpose to buy a couple eyepieces to get a barlow. Ultimately if you end up liking the reducer, you will probably want a barlow of some sort to hit high power with the reducer. Although 2.5x might be a little much. 

 

There are some tall, heavy 1.25" eyepieces that I might be nervous about putting in the Powermate given the Powermate wouldn't fully seat in a 1.25" diagonal. Some Delos, hyperwides, etc.


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#23 AaronF

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Posted 31 May 2024 - 03:15 PM

Tele Vue eyepieces are a lot more expensive to buy from outside the USA.

Have you considered the Baader Morpheus series? Morpheuses are £229 versus £379 for the Deloses.

They have a slightly wider FOV, too. And you may have seen recently that Don likes them a lot.


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#24 Chirpy73

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Posted 01 June 2024 - 07:53 AM

Tele Vue eyepieces are a lot more expensive to buy from outside the USA.

Have you considered the Baader Morpheus series? Morpheuses are £229 versus £379 for the Deloses.

They have a slightly wider FOV, too. And you may have seen recently that Don likes them a lot.

Hey Aaron, yes I saw Don had gone down that route as well, so high praise indeed!  Morpheus was definitely on my shortlisted EPs - along with Explore Scientific's.  

 

Interesting point about TV pricing in the UK too though... I'd been buying 2nd hand just as and when they come up - but, I'm bound to have a work trip to the US at some point, so will check the $ price at at the time and might come back with more in my packing than I went away with!!!  lol.gif lol.gif lol.gif


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#25 Chirpy73

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Posted 03 July 2024 - 03:17 PM

Hmm. See below. Look up the Celestron Xcel LX series.

http://astro-talks.r...opic.php?t=1483

So the two Xcel LX eyepieces that you intend to replace with the Powermate are the stars of the series, both getting excellent scores and essentially perfect at F10. As a matter of fact, if you scroll down to the Panoptics, you will see that none of them quite got the coveted yellow highlight. Granted the 19 wasn’t tested. Of course with the Powermate the Panoptics would have better edge correction, but the truth is, you could easily use the Xcel LX or Panoptics at F4. At F10 they will both be basically perfect. So you are upgrading from 60 AFOV to 68 AFOV. The 7Xcel LX is actually 62 AFOV. With the 24 Panoptic, it is 65 AFOV and replacing a 59 AFOV. So we are really just talking about a 10% increase in AFOV. Do you want to mess with a barlow just to get a 10% wider view?

The 15 Starguider isn’t that well known. The 12 Xcel LX is fine but not a standout. I could see a 13 Nagler or something. I’m not sure about Delite as you are only upgrading from 60 to 62 AFOV, and it is way more expensive. Even against mediocre eyepieces, it could be hard to tell a difference at F10. I would hate for you to spend $300 and feel like you can’t tell a difference. At least with the Nagler, you could tell a difference. Like 30% wider.

So yeah I would look more at a 13 Nagler, or at least a 14 Delos to get a wider view. If you are going to spend this kind of money, you want to be able to see a noticeable difference, not squinting and trying to convince yourself that the Delite is better than the others.

Below that, I would just stick with the Xcel LX unless you want to go ultrawide. 9 and 7 Nagler would work. Obviously more expensive than a Powermate. But I just don’t think I would want to bother messing with a barlow just to get 65 instead of 59 AFOV, or 68 instead of 62. Not worth the hassle. Panoptics are nice, but they aren’t magical. I just really question if you would see any difference other than a minor AFOV difference, unless there is something wrong with your Xcel LXs (dust/dirt inside, etc.).

Hey Scott, I wanted to feedback and thank you again for a lot of the points you made across your various responses to my thread.  

 

I've ruminated over the past few weeks, and really took on board your advice around the benefits of the EP's I already own; as well as the 'practical' pro's & con's of introducing Barlows & Powermates. (...for negligible FOV gains)

 

Accepting that in the UK the seeing isn't great, I've concluded that perma-fitting the f/6.3 Focal Reducer I already own (thereby not installing/uninstalling it in the dark) still presents me with a great set of usable magnifications (x30 up to x145 @ f/6.3) but with benefits of wider TFOV, exit pupil, & brightness improvements. 

 

Having then debated the various Barlow options (i.e importing the 1.6x, or going TV Barlow 2x, or TV PM 2.5x, etc) I've come to appreciate your concerns about the added weight, risk of damage with ill-paired combinations, and of course the added hassle of carrying and fitting them when viewing, and decided one is unnecessary. 

 

The only future component of my jigsaw now is your other suggestion - a Nagler! A 5mm would give me x189 with the FR fitted, which I think will be plenty on a really good day here in blighty...

 

As a fall back - if I do get uncharacteristically good UK seeing, I can then opt to remove the FR and default to x47 up to a scope maximum x300 at f/10, with no added PM's or Barlows.

 

It feels like a good solution to me anyway; it protects current investments, there's no extra devices adding weight/complexity, and no extra cost.  (unless I get the 5mm Nagler, which will be on the used market!)

 

Much appreciated, Jon waytogo.gif




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