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Finally--a stock 6" f/5 w/2" focuser--Omni XLT 150

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#126 Starman81

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Posted 24 April 2013 - 01:35 PM

Give us a first light report!

:ubetcha:
Mike


What I wrote above is my first light report! It's not much, I know. I really do need to get in more time with this scope.

Glad to hear that it can be BV'ed with, even though an OCA is required. The powers are pretty low and fields pretty wide, still, I would imagine, even with a 1.9x OCA.

#127 Sarkikos

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Posted 24 April 2013 - 01:44 PM

Starman81,

My post was intended for Locoman. You must have slipped in your post immediately before I answered Locoman. It is a good idea to put the name of the person you're responding to or a quote from the person's post at the top of your post. I need to do that more often!

Mike

#128 Locoman

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Posted 24 April 2013 - 02:45 PM

Starman81,

My post was intended for Locoman. You must have slipped in your post immediately before I answered Locoman. It is a good idea to put the name of the person you're responding to or a quote from the person's
post at the top of your post. I need to do that more often!

I received my 150 xlt yesterday with no damage at all. It sure is a good looking scope and the two inch crayford is a big bonus. First light may be a while though!
Doug

Mike



#129 MikeCatfin

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Posted 25 April 2013 - 02:56 PM

Looks like I missed out on this deal. It appears that it is both out of stock and the price listed is now $269.00.
Oh well, he who hesitates....

#130 JimMo

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Posted 25 April 2013 - 04:07 PM

Dude, you have my old avatar. Damn your eyes. :grin:

#131 Sarkikos

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Posted 26 April 2013 - 06:15 AM

He must be t.r.'s brother!

:grin:
Mike

#132 Sarkikos

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Posted 26 April 2013 - 07:12 AM

Last night I made another attempt to come to focus with my binoviewer in the XLT 150. I took the stock 1.25" adapter out of the focuser and inserted the low profile adapter from my Paracorr. I put in the binoviewer and tried to focus on the Moon from a window in my house. I used the same eyepieces as when I binoviewed the Moon a few nights ago.

None of them would come to focus with the binoviewer in native mode. Not even close. Maybe if the 2" focuser were replaced with a low-profile it could be done, but I doubt even that would work. Anyway, I don't think it would be cost-effective. I'm not doing it. As I said, I've never had a Newt that would come to focus with a binoviewer without using a Barlow or OCA.

Mike

#133 Sarkikos

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Posted 29 April 2013 - 01:43 PM

I also looked at Saturn with the XO 5.1 and Nagler Zoom. The image began to become less sharp than I like below about 4mm (187x, 31x per inch), probably because of the average seeing. I could see Cassini's Division around nearly the entire visible ring. A wide, dusky SEB was easy, and the SPR was nearly as easy to see.


This needs to be corrected. It was the NEB and NPR, not SEB and SPR. My excuse is that I had recently first lighted a 6" SCT, which does not flip the image - a source of confusion between the two scopes. I try to catch these mistakes before the editing time-limit elapses for a post.

Mike

#134 Pinbout

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Posted 06 May 2013 - 10:03 AM

Last night I made another attempt to come to focus with my binoviewer in the XLT 150. I took the stock 1.25" adapter out of the focuser and inserted the low profile adapter from my Paracorr. I put in the binoviewer and tried to focus on the Moon from a window in my house. I used the same eyepieces as when I binoviewed the Moon a few nights ago.

None of them would come to focus with the binoviewer in native mode. Not even close. Maybe if the 2" focuser were replaced with a low-profile it could be done, but I doubt even that would work. Anyway, I don't think it would be cost-effective. I'm not doing it. As I said, I've never had a Newt that would come to focus with a binoviewer without using a Barlow or OCA.

Mike


Last night I was playing around with my 8"f6 tube dob using the binos with no compensator.

I pointed the scope at zenith and with the primary sitting on a "pedestal"[a paint can] I slid my tube down till I could reach focus.

The primary wound up 4" in from standard position. When I put the numbers in newt for the web, I'll have to change the secondary from 1.5" to a 2.14" to get 100% light.

So if you want to use the binos with no compensator you'll have to use a different cell mounting plate that allows you to move the primary a lot closer to the secondary [4"]. I'm sure your stock secondary is big enough, they tend to oversize them... :grin:

#135 Sarkikos

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Posted 07 May 2013 - 10:24 AM

I have a Z8 f/6 which is probably similar to the Dob you're describing. The stock diagonal is somewhat oversized. I actually canabalized a smaller diagonal from a 5" f/5 Newt to replace the one in the Z8, to achieve a smaller CO%.

For myself, I'm not too gung ho about moding any of my Newts so they would be able to binoview without an OC or Barlow. My old model Burgess Binoviewer has a relatively narrow CA in any case, so there wouldn't be much point to it. I use my binoviewer almost exclusively for planet/lunar. I'm not really too interested in binoviewing for low-power wide-field.

I suppose, though, that moding the 6" f/5 for richfield binoviews at a dark site wouldn't be a bad idea. I guess I could raise the mirror cell up somehow. I have an old mirror cell from an ancient 6" f/8 in the attic. For richfield, it might be a good idea to take the diagonal that was in my Z8 and put that in the 6" f/5.

But then I should replace my binoviewer with one that has a wider CA to accommodate the wider field stops in low power eyepieces. Then it starts to cost some money. Otherwise it would be a waste of time, because there would be vignetting in the binoviewer with loss of light and constriction of the effective field of view.

Mike

#136 uniondrone

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Posted 07 May 2013 - 11:39 AM


Man, oh, man...

You're making me regret not getting the Portamount back at the Ford Club Swap&Shop Expo! :foreheadslap:

Chuck

#137 Pinbout

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Posted 07 May 2013 - 12:52 PM

I suppose, though, that moding the 6" f/5 for richfield binoviews at a dark site wouldn't be a bad idea. I guess I could raise the mirror cell up somehow. I have an old mirror cell from an ancient 6" f/8 in the attic. For richfield, it might be a good idea to take the diagonal that was in my Z8 and put that in the 6" f/5.



I had mine in my 127f5.5 fractor this last weekend at a dark site and some of the views were awesome. I took off the corrector and removed the diagonal, and while looking around aruiga I couldn't keep my mouth shut. and everything was crisp. it was low to the horizon so I could set it up as a straight thru view. later while it wasn't even totally dark yet I had m81&82 in the same view with the diagonal and 1.6 comp. 82 was very distinct.

I spent more time with my 127 and bino's than my truss 8"f6 that has a good figure on it. :grin:

#138 Starman81

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Posted 25 May 2013 - 09:29 PM

I got a chance to second-light my Omni XLT 150 last weekend at a club observing night... There was a waxing Moon to contend with but splitting doubles in Lyra and views of Saturn were pretty good. Seeing was only average, though and the CD was elusive in all scopes out there that night. Views of M13 were decent as well, I thought a bit faint at 150x. I realized later on that my XW 5 was NOT in the focuser (150x) but instead the XW 7 (107x), so that explains that.

CN'er JimMo let me try his ES100 25mm in the scope--3.3* TFOV, 30x, wow what an immersive view! I didn't even have to rebalance the scope. One thing I must add though, the XLT 150 was very shakey for some reason on the AT Voyager mount. So shakey that when other observers walked around near the scope on the pavement, the scope shaked A LOT and this was with the extension pier on the Voyager mount. I'll have to make it a bit more stable...

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#139 belgrade

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Posted 13 June 2013 - 10:01 PM

Anyone sells the new version OTA-only with a 2" focuser? Telescopes.net advertises the model with the 1.25" only, according to the site.

#140 CollinofAlabama

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Posted 17 June 2013 - 11:53 PM

It's said that since Lincoln was President. It's been pointed out repeatedly -- the specs say its a helical focuser -- the ninnies won't update it. LAZY. However, if you call them, they will swear on a stack of Bhagvad Gitas that it ships with a 2" single speed Crayford (à la Orion dobs). Don't let their poorly maintained website fool you.

#141 Sarkikos

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Posted 13 September 2013 - 07:38 AM

I finally took out a telescope last Friday after three months of recuperating from back and hip injuries. Not my 10" Dob, but this XLT 150 on a Voyager II alt-az mount. I didn't want to take a chance on a relapse.

A star test on Polaris showed that this 6" f/5 Dob has a somewhat different diffraction pattern when comparing infocus and outfocus at 5 waves, not so much at 10. Maybe 1/5 wave lower order spherical aberration when comparing my memory of the diffraction pattern to examples I've seen online. Unfortunately I didn't have Suiter's Star Testing with me. But so far my C6 SCT seems to have a better star test than the XLT 150, with no difference seen at 5 waves with the C6.

I need to do a more thorough star test of the XLT 150 on my porch at home, viewing Polaris, with my copy of Star Testing at my side. I don't like to spend much time testing equipment when I'm at a dark site.

(I've given a more detailed account of my observing session in another thread.)

Mike

#142 Phillip Creed

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Posted 13 September 2013 - 10:00 PM

Even if it's a 1/5-wave mirror, that 6" f/5 reflector is going to be waaaaaay sharper on planets and globs than a 6" f/5 achro. I think it's really cool there's a 6" f/5 reflector out there with a 2"-focuser that sells for as little as a it does. I had a 6" f/5 Celestron Omni achromat that was great for a widefield viewing, but a 6" f/5 achro is a "widefield uber alles" scope. Get the power above 100X, and things started getting ugly on planets.

At the time, I couldn't get a widefield instrument like this with a 2" focuser unless it was a fast achromat. It's refreshing to see a far more versatile instrument with the same aperture and focal length being marketed out there.

Clear Skies,
Phil






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