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2" Diagonal upgrade for Nexstar 6se...FIRST POST

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#26 giantfan92

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Posted 04 January 2013 - 07:41 AM

http://www.opticsmar...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!

#27 CelestronDaddy

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Posted 04 January 2013 - 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

#28 jturie

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Posted 04 January 2013 - 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!

#29 Arthur Dent

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Posted 04 January 2013 - 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

#30 donnie3

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Posted 05 January 2013 - 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.

#31 hazilim

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Posted 12 January 2013 - 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

#32 giantfan92

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Posted 17 January 2013 - 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.

#33 kkokkolis

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Posted 17 January 2013 - 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.

#34 giantfan92

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Posted 18 January 2013 - 09:59 AM

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

#35 FishInPercolator

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Posted 03 June 2013 - 11:25 AM

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?

#36 zymon

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Posted 01 July 2013 - 03:19 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.

#37 hawk

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Posted 02 July 2013 - 05:05 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.


#38 mclewis1

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Posted 03 July 2013 - 10:39 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.

#39 zymon

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Posted 04 July 2013 - 10:35 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

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.

#40 mclewis1

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Posted 04 July 2013 - 12:32 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.

#41 Arctic_Eddie

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Posted 04 July 2013 - 01:18 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.cloudynig...3619392/page...

#42 FishInPercolator

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Posted 05 July 2013 - 08:31 AM

Mark, I have to concur :)

#43 zymon

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Posted 06 July 2013 - 01:09 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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