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Julio
sage
Reged: 01/18/07
Loc: Pembroke Pines ,FL
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Re: Maksuton-Newtonian vs Schmidt-Cassegrain
[Re: Tanveer Gani]
#5650935 - 01/29/13 06:51 PM
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Lovely Tanveer, great handywork!
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Julio
sage
Reged: 01/18/07
Loc: Pembroke Pines ,FL
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Re: Maksuton-Newtonian vs Schmidt-Cassegrain
[Re: titanio]
#5650941 - 01/29/13 06:55 PM
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Wow que telescopio, lovely setup!
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titanio
sage
Reged: 02/15/09
Loc: Alicante, Spain
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Re: Maksuton-Newtonian vs Schmidt-Cassegrain
[Re: Julio]
#5652226 - 01/30/13 12:29 PM
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Gracias Julio
Now I have my MN86 on a very nice Losmandy GM8
Toni
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Tanveer Gani
scholastic sledgehammer
Reged: 11/02/06
Loc: Washington State
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Re: Maksuton-Newtonian vs Schmidt-Cassegrain
[Re: titanio]
#5652311 - 01/30/13 01:20 PM
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@Julio, @Paul: thanks! I didn't do much, just sent Mark Wagner at 1st Base Mounts and Rings the specs and he sent me a first-class CNC machine cut kit using top-notch plywood. Putting it together and finishing it took but a few days of evening work. If you need a dob mount, his shop is highly recommended.
@Titanio: You can't do better than a Wirth built tube with deluxe Intes optics. I think you'll want to hang on to that OTA for life. One question for you though: what are you doing to get your Mark V (?) to come to focus? I used to have a Siebert OCA that would allow Sibert BV's to come to focus but I sold the whole package and now have a Mark V but it won't come to focus with a regular 2" barlow. I think I need an A-P BARCON to use just the lens as an OCA.
Tanveer.
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Paul Hyndman
sage
Reged: 07/13/04
Loc: Connecticut Shoreline USA
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Re: Maksuton-Newtonian vs Schmidt-Cassegrain
[Re: Tanveer Gani]
#5653328 - 01/30/13 10:16 PM
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Quote:
I used to have a Siebert OCA that would allow Sibert BV's to come to focus but I sold the whole package and now have a Mark V but it won't come to focus with a regular 2" barlow. I think I need an A-P BARCON to use just the lens as an OCA.
Tanveer, I don't know about current availability, but the Denkmeier OCS did a spendid job as a low-amplification relay lens for my MN86, although there was a slight amount of field curvature at the edge and mild vignetting (most likely from the small secondary).
Here are some sample shots comparing it to a 2X Powermate. Focus was shifted outwards out from a -12mm (inside) position to a +25mm (available) position.
Paul
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maknewtnut
Member
Reged: 10/08/06
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Re: Maksuton-Newtonian vs Schmidt-Cassegrain
[Re: jsrj98]
#5653420 - 01/30/13 11:31 PM
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I just read one fellow's negative comments about a couple of I-M MakNews he owned. Opinions can and will vary, and that's fine. IMO, most folks should be able to substantiate WHY they hold a given opinon.
In this instance, pointing out the illuminated circle size of ANY 5" f/6 Newt based design is a foray into the obvious. As another participant mentioned, this topic, as it relates to these telescopes, seems to come up on this forum with some frequency. It's noteable that in most instances, the poster also refers to illuminating their 31mm Naglers. I'm confused. Why is full illumination of ANY eyepiece with a 41mm field stop in a telescope with a 30mm secondary mirror even a topic of discussion?
I've been a long time advocate of weighing the merits of comments and reviews. One method one can utilize to separate the wheat from the chaff are common threads. One person with an axe to grind is fairly easy to spot when they complain about what almost everyone else compliments. I was taken aback about comments on cooldown with I-M MakNewts. Why? Because that's an attribute an overwhelming percentage of users have offered kudos for.
To continue along the same line with 'issues' about illuminated field size for imaging after adding a filter wheel....given the specs for backfocus, I'm confused as to why you were surprised. Perhaps others can share their successful imaging results. Names like Paul Hyndman and Dean Salman leap to mind (to name just a few) .
Most Cassegrain variants (which includes MCT's as well as SCT's) will provide you with FAR more backfocus most Newtonian based designs. Even given that, given the same simple mathematics, I wish you luck fully illuminating a 31mm Nagler with your new C8..but enjoy regardless.
I sincerely mean that last part. Enjoy John...but c'mon!
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jsrj98
member
Reged: 02/21/08
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Re: Maksuton-Newtonian vs Schmidt-Cassegrain
[Re: maknewtnut]
#5653529 - 01/31/13 02:04 AM
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If I came across as severely negative against the Mak-Newts I owned that was NOT my intention. I really enjoyed them. However, from an imaging standpoint the ones I owned did have their limitations, which I well understood. For several years I happily imaged with an SX H9 using both scopes with excellent results. When I moved on to a larger chip camera their small secondary proved to be a drawback that I eventually decided I couldn't live with. Astronomy, and especially imaging, is a journey, and you often don't fully know what you are getting into when you start down a particular path.
As I mentioned in my previous post, at the time I owned them I did not also own a Nagler (all my free cash was spent on imaging equipment) so I can't comment on the view with them using those type of eyepieces. I really have no idea if the light falloff would be acceptable-- especially with a 31mm.
When I moved on to an APO refractor for imaging, I stopped taking flats because there was no need to do so-- the chip was completely illuminated. Of course, I did need to use a field flattner (there are trade offs everywhere).
I haven't imaged yet with my Edge8, I'm waiting for the dedicated reducer to be shipped-- I have no desire to image at F/10. Therefore, I have not yet measured any light fall off with the scope. I can tell you, however, that the image plane is completely flat to my eye. Even my APO had a field curvature that I could detect with a Nagler. Not so with the Edge.
Would a 6" or 7" Mak-Newt deliver a better planetary image than the Edge8? Probably. I didn't buy my first SCT for that purpose only, but as an all-around scope-- competent for both visual use and imaging. I can tell you that tonight it delivered the best view of M42 of any scope I've owned, and that includes the Mak-Newts, a customized 8" 'planetary' Newt with superb optics and a very small secondary and nice 10" Dob.
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roadi
Pooh-Bah
Reged: 08/18/07
Loc: GGS
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Re: Maksuton-Newtonian vs Schmidt-Cassegrain
[Re: jsrj98]
#5653627 - 01/31/13 05:41 AM
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Quote:
I can tell you that tonight it delivered the best view of M42 of any scope I've owned, and that includes the Mak-Newts, a customized 8" 'planetary' Newt with superb optics and a very small secondary and nice 10" Dob.
One reason for this could be you've had your best all time seeing this night! other than this just doesn't make sense.
Other reasons might be that those other " optimized ??" scopes you compared the views with, didn't really have such great optics as you say.
That said, I find it great to read so many good reviews of the new Edge HD, "Improved QC" wich might ensure future customers a certain level of quality is great!
but implying, that mass produced equipment are better than that of a niche production from companies crafting limited numbers aiming at through out quality rather than price point, is silly.
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maknewtnut
Member
Reged: 10/08/06
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Re: Maksuton-Newtonian vs Schmidt-Cassegrain
[Re: jsrj98]
#5653883 - 01/31/13 09:19 AM
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One thing does appear to be sure. The Edge HD's seem to be making many folks happy, which is great. Kudos to Celestron. Enjoy!
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