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giantfan92
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Reged: 01/01/13

2" Diagonal upgrade for Nexstar 6se...FIRST POST
      #5603083 - 01/03/13 02:07 PM

Hello everyone this is my first post on this forum!
First of all let me say that this nexstar 6se is absolutely a blast and I am already hooked on this hobby just two weeks in!!!

I have heard some conflicting information about installing a 2" diagonal on my nexstar 6se.(Telescopes.com beleives it does not accept a 2" diagonal). So after hearing this I decided to go ahead and purchase two 1.25" EP's.
Baader hyperion 21mm(I've heard it goes to 2") and Edmund 28mm RKE

I viewed a 2" on a friends dob and I have to say I was impressed with the comfort of the EP and I would like the ability to upgrade to nicer EP's on my nexstar in the future (Cost is not a big factor for me)

Would you guys recommend that I upgrade to a 2"? Or better than that do you guys even think a 2" is compatible?

Any help would be awesome I am already completely in love with this hobby and forum and I greatly appreciate any replies!


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giantfan92
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603107 - 01/03/13 02:18 PM

Oh let me also note that I do have a power-pack and a dew shield after I saw a lot of people recommending them. Dew shield comes in tomorrow!

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Midnight Dan
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603112 - 01/03/13 02:23 PM

Hi giantfan92 and welcome to the forum!

The 6SE will definitely accept a 2" diagonal. You'd want to get an SCT-type diagonal that threads directly onto the rear cell. You remove your current visual back piece, and install the diagonal instead. Nearly all 2" diagonals come with a 1.25" adapter so you'll be able to use your 1.25" eyepieces too.

Note that for any 1.25" eyepiece, there will be no advantage in moving to a 2" diagonal. So, while your Baader 21mm Hyperion will indeed fit into a 2" diagonal (with or without an adapter), the view you see through it will be the same as with a 1.25" diagonal.

There are 2 advantages of a 2" diagonal. One is that it is a more secure connection to the scope for larger eyepieces, cameras, binoviewers, and other heavier accessories. The other advantage is that it allow you to use 2" eyepieces.

As you buy eyepieces with longer focal lengths and wider views, you reach a point where it will no longer fit into a 1.25" barrel. In the Baader lineup, a 24mm/68 eyepiece is at this maximum. To achieve any wider view, the eyepiece needs to be designed as a 2" rather than a 1.25". And of course if the eyepiece is designed as a 2", then it needs a 2" diagonal.

The Baader combo eyepieces, with the 1.25"/2" design, are really just 1.25" eyepieces. They have a 2" part to the outer barrel so that they fit into a 2" diagonal without an adapter, but the optics are designed to fit into a 1.25" barrel.

-Dan


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Arthur Dent
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Midnight Dan]
      #5603118 - 01/03/13 02:28 PM

Hi Giant, a warm welcome to the NexStar forum.



Yes, the 6SE will accept a 2" diagonal as shown here in this photo of my 6SE on the rear patio at home. As Dan says, you need a diagonal that has an SCT threaded locking-ring.



Also seen in this photo is a skylight filter (which is between the diagonal and the rear cell of the scope - which is why there are TWO locking rings) my RACI finder (behind the scope) and, on the top, a multi-reticle finder (much better than the standard red-dot finder IMHO). The EP is a Celestron Ultima 35mm.

Art



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giantfan92
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Arthur Dent]
      #5603128 - 01/03/13 02:32 PM

Wow!! I really appreciate the quick reply both of you guys!! What 2" diagonal would you guys reccomend?

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Arthur Dent
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603134 - 01/03/13 02:35 PM

William Optics 2" Carbon Fibre

Link: 2" WO Carbon Fibre Diagonal

Art


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jhirsch
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603150 - 01/03/13 02:43 PM

FIrst off welcome aboard giantfan92. As you already know you've found THE site to grow your understanding and appreciation of the night sky.

Now to your questions.... Yes you can attach a 2" diagonal to a 6se. However there are a few things to consider.

1. Be careful of the clearance of the diagonal to the base while pointed at zenith.
2. While a 2" diagonal will allow you to obtain a slightly larger FOV there is no way the 6se can compete w a dob when it comes to wide views. Just can't break the laws of physics....
3. If I remember correctly I thought I had read somewhere that there are/were issues with the threads on the 2" Astro-Tech diagonals. maybe someone else can chime in on that. I have a 2" GSO and it threads on just fine. The threads are very fine so when attaching be careful that you don't cross thread it.
4. Possibly consider a focal reducer also. Drawback to the focal reducer is it WILL cause diagonal/base clearance issues when pointed at zenith unless some slight modifications are done to the dove tail. You can find them in the Links and Best of the Celestron NexStar Fourm.

Again Welcome aboard and Clear Skies

Jerry


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giantfan92
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Arthur Dent]
      #5603166 - 01/03/13 02:55 PM

Thanks for the reply! What exactly would the benefits of a focal reducer be for this scope? Sorry for the newborn questions I'm on my phone at work!

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jturie
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Arthur Dent]
      #5603169 - 01/03/13 02:57 PM

Quote:

Hi Giant, a warm welcome to the NexStar forum.



Yes, the 6SE will accept a 2" diagonal as shown here in this photo of my 6SE on the rear patio at home. As Dan says, you need a diagonal that has an SCT threaded locking-ring.



Also seen in this photo is a skylight filter (which is between the diagonal and the rear cell of the scope - which is why there are TWO locking rings) my RACI finder (behind the scope) and, on the top, a multi-reticle finder (much better than the standard red-dot finder IMHO). The EP is a Celestron Ultima 35mm.

Art






Art--very nice setup. Can you supply the details of your RACI and the finder? What are they and how did you attach both of them to the 6SE?

Not thrilled with my red dot, and am looking for alternatives.


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giantfan92
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Reged: 01/01/13

Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: jturie]
      #5603203 - 01/03/13 03:12 PM

Great info guys! I want to upgrade to the 2" because I see myself buying like a 12" dob after I learn the skies really well.

Art, that is a very attractive looking scope!


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Midnight Dan
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603317 - 01/03/13 04:25 PM

Hi giantfan92,

Pretty much any of the major brands of 2" diagonal will do. Just be sure to get one that's has a dielectric coating. That makes the mirror surface much harder and resistant to scratches from cleaning. You DON'T need a "quartz dielectric", just "dielectric coating".

Some of the well known, reasonably priced brands are GSO, Astrotech, and William Optics. You probably won't see one bit of difference between the brands when you're looking through them. But the William Optics is just cooler looking on the outside! (costs more too, unfortunately).

-Dan


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giantfan92
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Reged: 01/01/13

Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Midnight Dan]
      #5603357 - 01/03/13 04:50 PM

Thanks Dan! I will most certainly be purchasing one of those. I've had almost as much fun buying more stuff for my scope as I have had observing lol!

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jhirsch
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603364 - 01/03/13 04:56 PM



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giantfan92
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603412 - 01/03/13 05:37 PM

Hey guys this looks like a really good buy!

Any opinions?

http://agenaastro.com/gso-2-90-99-quartz-dielectric-sct-mirror-diagonal.html

Edit: Would you guys recommend a particular barlow with this?

Lots of questions forgive me!

Edited by giantfan92 (01/03/13 05:49 PM)


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Arctic_Eddie
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603424 - 01/03/13 05:51 PM

I have this one which works fine with the 2" diagonal on my 6SE.

http://agenaastro.com/gso-2-2x-ed-barlow-lens.html


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giantfan92
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Reged: 01/01/13

Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Arctic_Eddie]
      #5603431 - 01/03/13 05:57 PM

Quote:

I have this one which works fine with the 2" diagonal on my 6SE.

http://agenaastro.com/gso-2-2x-ed-barlow-lens.html




Thanks! I was actually just looking at this, its good to hear from someone with the same scope.


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Midnight Dan
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603511 - 01/03/13 06:49 PM

Hi giantfan92:

That GSO model from Agena Astro will work fine. Nice thing about Agena is that they nearly always have free shipping.

I have the same barlow that Eddie mentioned above, and it is an excellent quality barlow for a good price. Someone here on Cloudy Nights did a comparison of 2" barlows a while back and this one came out even with or slightly ahead of some much more expensive models.

Seems to be out of stock now at Agena, but if I remember correctly, it was around $60 or so.

-Dan


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Arctic_Eddie
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Midnight Dan]
      #5603535 - 01/03/13 07:03 PM

It also comes with a 1.25" adapter. Both have brass compression rings.

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giantfan92
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Reged: 01/01/13

Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Arctic_Eddie]
      #5603555 - 01/03/13 07:19 PM

Quote:

I have this one which works fine with the 2" diagonal on my 6SE.

http://agenaastro.com/gso-2-2x-ed-barlow-lens.html




Just bought this gso 2" 90 deg, seems like a great price! I have been googling that barlow a ton but I cant seem to find it! Now on to 2" eye peices... I'm gonna be hooked up!

If only it would stop raining lol


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giantfan92
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Reged: 01/01/13

Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603584 - 01/03/13 07:39 PM

http://www.opticsmart.com/apertura-2-inch-2x-ed-barlow-lens-with-compression-...

Looks like I am going to settle for this. From everything ive seen it seems like apertura is the same thing as GSO.

Lets hope im right. Anyone have input on apertura?

Thanks!


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Arthur Dent
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603595 - 01/03/13 07:44 PM

Hi Jack

Can't remember the make of the RACI off the top of my head but I'm 99% certain that it is an Antares.

Multi-reticle finder (MRF) is the same kind of finder used as a gunsight with an appropriate quick-release shoe.

Both are screwed into the aluminium casting of the rear cell. The shoe for the RACI (also quick-release) has holes that were of a different spacing to the holes of the Celestron RDF - so I removed the rear cell, drilled and tapped the holes and then replaced the rear cell.

I documented the procedure here: linky-dink

Hope this helps,

Art


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giantfan92
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Reged: 01/01/13

Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603629 - 01/03/13 08:00 PM

Quote:

http://www.opticsmart.com/apertura-2-inch-2x-ed-barlow-lens-with-compression-...

Looks like I am going to settle for this. From everything ive seen it seems like apertura is the same thing as GSO.

Lets hope im right. Anyone have input on apertura?

Thanks!




Just bumping this so people can view on the second page.


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chuck56
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603772 - 01/03/13 10:01 PM

Not to highjack the thread but how did you get the ota that far back on the dovetail bar?

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Midnight Dan
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5603857 - 01/03/13 11:03 PM

Quote:

http://www.opticsmart.com/apertura-2-inch-2x-ed-barlow-lens-with-compression-...

Looks like I am going to settle for this. From everything ive seen it seems like apertura is the same thing as GSO.

Lets hope im right. Anyone have input on apertura?

Thanks!




Looks like the same one as the GSO to me. Most of these items are sourced from the same far-east manufacturer and just dressed up slightly differently depending on who's selling it.

-Dan


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Arthur Dent
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Midnight Dan]
      #5604112 - 01/04/13 05:33 AM

Hi Chuck

Nothing special. No extra bars/spacers etc. Just pushed the OTA as far forward as it would go until the rear cell fouled on the arm's plastic shroud (cover).

Should I need the OTA to be more forward, I'd need a rail or spacers between the dovetail and the OTA.

Art


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giantfan92
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Reged: 01/01/13

Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Midnight Dan]
      #5604190 - 01/04/13 07:41 AM

Quote:

Quote:

http://www.opticsmart.com/apertura-2-inch-2x-ed-barlow-lens-with-compression-...

Looks like I am going to settle for this. From everything ive seen it seems like apertura is the same thing as GSO.

Lets hope im right. Anyone have input on apertura?

Thanks!




Looks like the same one as the GSO to me. Most of these items are sourced from the same far-east manufacturer and just dressed up slightly differently depending on who's selling it.

-Dan




Thanks Dan, looks like I will be grabbing this 2" barlow!


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CelestronDaddy
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5604840 - 01/04/13 01:44 PM

Well I did upgrade but not to a 2". I got a 1.25" Williams Optic Dielectric. Should be better than the stock diagonal that I was using. Got it for a decent price. May look at moving to a 2" down the road though. Tony

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jturie
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: CelestronDaddy]
      #5605004 - 01/04/13 03:12 PM

Art:

Nice job, but your pics gave me the shakes. No way would I ever have the courage and skillset to do what you did!


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Arthur Dent
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: jturie]
      #5605053 - 01/04/13 03:45 PM

Aw go on, Jack. All I needed was blind ignorance and a screwdriver. Anyone can do that!

Seriously, I reasoned that as long as I asked questions first and documented what I did step-by-step as I disassembled the scope, I should be able to put it back together again.

Thankfully, this cunning plan worked.

What I didn't want to do was entrust an expensive RACI finder to a single retaining screw or an expensive multi-reticle finder to strong double-sided tape (no matter how strong the manufacturer claimed the tape was).

Art


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donnie3
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Arthur Dent]
      #5607277 - 01/05/13 08:51 PM

i have a 6"se and a meade 8"sct ota that i use on the se mount, works great. ive used my 2" diagonal on the 6" with a 26mm 2" q70 and was not impressed. using it on the 8" was a joy. truly wide field. using it on the 6" i kept getting black outs around the edge of the fov.

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hazilim
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: donnie3]
      #5619145 - 01/12/13 02:09 PM

I've used the AstroTech 2" SCT dielectric diag on both the 6SE & 8SE. Quality is great, the price is reasonable, & the diag clears the mount with room to spare.
Bob


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giantfan92
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Reged: 01/01/13

Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: hazilim]
      #5628249 - 01/17/13 03:01 PM

Whew, quite a delay in my posting, I mostly have been looking up! I got the GSO Quartz 2" diagonal and I am glad I did because it feels very sturdy. I spent some time (9 hours lol) at a nearby darkspot with a friend and he had a 8" dob but we spent most of the time looking through my nexstar because of the very good goto tracking on it.

In addition to the diagonal I also received a 28mm RKE a 21mm baader hyperion and an 11mm ES 82 degree and wow I am blown away!!!

I feel like for now those EP's will be fine and the only thing I have left to purchase is a 0III filter because I really like looking at dso's.


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kkokkolis
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5628388 - 01/17/13 04:07 PM

I would recomend a Narrowband UHC filter over an OIII. Not the Baader or Celestron UHC-s (they are Broadband) but something like the Orion Deepsky, Lumicon UHC or Thousand Oaks LP2.
Nice selection of eyepieces, that give the critical 2mm and 1mm exit pupils. Since you have a 2" diagonal and the RKE is narrofield, consider later a Baader Hyperion Aspheric to get more field for some objects.


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giantfan92
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Reged: 01/01/13

Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: kkokkolis]
      #5629586 - 01/18/13 09:59 AM

Thank you! After hearing this and reading a huge filter review I will pick up one of these!

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FishInPercolator
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: Arthur Dent]
      #5899542 - 06/03/13 12:25 PM

Nice pic... how much clearance do you have with the 2" diagonal on the 6SE? What would need to be done in the event you decided to put an f/6.3 onto it?

Edited by FishInPercolator (06/03/13 12:50 PM)


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zymon
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: giantfan92]
      #5949102 - 07/01/13 04:19 AM

Is it true that if you have a Nestar 6/8 etc, and you get a very wide 2" EP and put it in a 2" diagonal, part of the image will be concealed because the base telescope was designed as a 1.25.
Sorry using very basic lanuage to discribe it as im a neewbie.


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hawk
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: zymon]
      #5951824 - 07/02/13 06:05 PM

Edit: Oops, I had listed the baffle size for the 8SE, not 6SE. Thanks for catching my error, Mark! It probably makes a bit more sense to upgrade the 8SE to a 2" than the 6SE.


Edited by hawk (07/03/13 11:53 AM)


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mclewis1
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: hawk]
      #5952950 - 07/03/13 11:39 AM

Since we're talking about a 6SE then yes the comment about "designed for 1.25" is very appropriate. The baffle tube opening is just under 27mm.

While an C8 ota has a larger rear opening, the SE scopes in general are not really intended for 2" accessories. Base clearance, counterbalancing, overall weight carrying capacity are all oriented towards the smaller lighter 1.25" stuff. Can you use 2" stuff, sure, but the point is the overall scope package wasn't designed with that capability in mind.

Personally I wouldn't go out and spend the extra money on new 2" accessories for either a 6 or 8SE unless I intended to use heavy stuff like binoviewers. Put some existing 2" stuff to good use, sure, but an SCT f6.3 focal reducer, a 1.25" dielectric mirror diagonal and a good 32mm Plossl or 24mm 68 eyepiece will also produce just about the same width views with very good quality fields.


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zymon
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: mclewis1]
      #5954636 - 07/04/13 11:35 AM

Quote:

Since we're talking about a 6SE then yes the comment about "designed for 1.25" is very appropriate. The baffle tube opening is just under 27mm.

While an C8 ota has a larger rear opening, the SE scopes in

Personally I wouldn't go out and spend the extra money on new 2" accessories for either a 6 or 8SE unless I intended to use heavy stuff like binoviewers. Put some existing 2" stuff to good use, sure, but an SCT f6.3 focal reducer, a 1.25" dielectric mirror diagonal and a good 32mm Plossl or 24mm 68 eyepiece will also produce just about the same width views with very good quality fields.




I also wondered about this. Whats the largest and widest EP that will fit on the 6/8SE then. How to say this - erm when you look through the lense how much bigger would the image be if we got a 2" diagonal.

Even if we did get a 2" diagonal you say we would never really get the full use of it. Interesting I read so many posts that have missed this point.


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mclewis1
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: zymon]
      #5954776 - 07/04/13 01:32 PM

You can physically use any 2" eyepiece on a C6, it's just at the very wide fovs that you won't be fully illuminating the outer field of view (vignetting). Many folks will just go ahead and use 2" gear and enjoy the wider fov and not care about any light drop off (most of us can actually tolerate quite a high percentage of light drop off) and for most that's a reasonable trade off (wider fov vs. some vignetting). I think the math says that just over 1.1 fov the vignetting starts. I often use a 1.75 setup in my C6 and only notice it a bit. With a 2" eyepiece in the 35-40mm range (1.5-1.75) I notice a bit more vignetting than with the 1.25"/focal reducer setup.

One thing you do need to watch for when viewing bright objects (moon, filtered sun, terrestrial in daylight) with long fl 2" eyepieces is the secondary shadow. This shows up as a dark center in the fov.

If all I had was a C6 I personally wouldn't spend the extra money on 2" gear ... I'd just get an SCT f6.3 focal reducer and a few good 1.25" eyepieces. If I had a C8 it would be a tougher decision. You get more benefit from 2" gear on a C8 because the baffle tube on the C8 is larger and therefore there will be less vignetting when you push the limits. A 2" SCT threaded diagonal and a 68 2" eyepiece in the 30-40mm range makes a nice wide field setup. What was often referred to as the ideal setup on a C8 is a Panoptic 35mm eyepiece (it's 38mm field stop exactly matches the baffle tube opening). Today there are many similar great choices in eyepieces for a C8.

Gear "creep" is a nasty little thing to watch for when upgrading. First it's a 2" diagonal and eyepiece, then to reuse the 2" diagonal on another scope you choose a 2" barrel model, then that means you'll also need a 2" visual back on the SCT. 2" eyepieces usually mean 2" filters so you'll end up duplicating filters, etc. etc. etc.

Before you take the plunge it's a good idea to work out what the actual benefit is vs. the costs.

Edited by mclewis1 (07/04/13 09:28 PM)


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Arctic_Eddie
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: mclewis1]
      #5954842 - 07/04/13 02:18 PM

My measurements from a few years ago show that the maximum FOV using 2" accessories is 1.32 using a 32mm 68 EP from Agena.

http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/3619392/page...


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FishInPercolator
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: mclewis1]
      #5955755 - 07/05/13 09:31 AM

Mark, I have to concur

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zymon
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Re: 2" Diagonal upgrade for Nexstar 6se...FIRST POST new [Re: mclewis1]
      #5957610 - 07/06/13 02:09 PM

Also I see that my 1.25 diagonal is very close to the bottom of the mount when I have the tube pointing up vertically. The clearance is soo small I doubt any 2" will fit.

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