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Where are the Mak-Newt people?

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#51 junomike

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Posted 31 May 2015 - 03:37 PM

Does anyone know what the CO is for the SW 190 Mct/Newt?

 

Jeff, does your MN86 with its small CO still illuminate longer focal length 2" eyepieces?  

 

Bill

Bill, It looks like the SW 190 MN is the same as the Orion 190 MN which has a 34% CO! 

I believe there is an older version with a smaller CO

 

Mike



#52 SkyRanger

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Posted 31 May 2015 - 05:08 PM

Got a chance to buy a Cerovolo 145 last year. With rotating rings on my GM-8,it's a joy to use.

GG

#53 Jeff B

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Posted 31 May 2015 - 05:36 PM

 

I have a wonderful Skywatcher MN190 Mak-Newt, but they seem to be orphans on Cloudy Nights. Where do they hang out?

Not many Mak-Newts are sold globally I suspect.  I've had a couple.  I prefer a straight Newt to a Mak-Newt to be honest.  It's just simpler, lighter and cheaper, with few drawbacks other than diffraction spikes from the spider arms.  I don't dislike them by any means.  I just don't find that they add enough extra compared to the more common similar alternative.

 

- Jim 

 

 

Good points Jim but the M-W Mak-Newts mitigate pretty much everything you mention except the cheaper part.    Also remember they have substantially less coma than an equivalent F ratio Newt (and adding a Paracor starts to complicate the Newt).  The meniscus is no more complicated nor more prone to dewing than the front element of a refractor and refractors are noted for their fuss-free-ness.

 

It does come at a hefty price though relative to a conventional Newt and the Mak-Newt is no exception to the good old Law of Diminishing Returns, but it's not flagrant about it either, especially compare to an equal aperture APO. 

 

Jeff


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#54 Jeff B

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Posted 31 May 2015 - 05:45 PM

Jeff, does your MN86 with its small CO still illuminate longer focal length 2" eyepieces?  

 

Bill

 

Bill, the fully illuminated spot is only about 4-5 MM so the big 2" eyepieces will have vignetting out at the edge and if I had to guess, I'd say around 40% or so, depending on the eyepiece.  Adding a moderate barlow (1.8X ish) will improve that number but then it cuts down on the FOV.

 

Jeff



#55 glend

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Posted 31 May 2015 - 06:11 PM

 

Does anyone know what the CO is for the SW 190 Mct/Newt?

 

Jeff, does your MN86 with its small CO still illuminate longer focal length 2" eyepieces?  

 

Bill

Bill, It looks like the SW 190 MN is the same as the Orion 190 MN which has a 34% CO! 

I believe there is an older version with a smaller CO

 

Mike

 

Actually the CO is 26%, as shown in most of the detailed advertising for the scope. This from the UK distributor:

 

"Central Obstruction: 50mm/26%"

 

From here:

http://www.opticalvi...-190mn_pro.html

 

 

The Orion and the Skywatcher have other differences, perhaps they were similiar when they both were entering the market but the Orion is gone out of production and the Skywatcher has continued to evolve.


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#56 Drew57

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Posted 26 July 2015 - 11:18 AM

At least one here in Minnesota...

 

I wanted a telescope since I was a young lad; and after learning, designing all sorts to build over the decades, etc. I decided what I needed was a 8" Newtonian RFT that could possibly even be hand-held or supported with a little bipod when camping in BWCA. Well, maybe a good thing it was never made, since optics and eyepieces have improved dramatically.

 

Finally purchased an ES 152 Mak-Newt on sale for a good price, and paired it with the newly updated iOptron iEQ30 Pro GEM also on sale. After a set of 4 ES 100o eyepieces & 2X focal extender, Hotech collimator, SV reticle eyepiece and a few filters, pelican cases etc.; I pondered the 127 lbs. of equipment while the sticker shock hopefully subsided.

 

Numb to the cost, I decided to just go all-in and fill out the kit with Kendrick dew control, 2" prime-focus adapter for my Canon, SBIG STi planetary cam with guiding kit, some ADM plates and mounts. I also made a 12V power distribution box with 5V USB and PowerPole connectors. Not sure I really want to know the total cost, but I figure the accessories can be used with other scopes in the future as I suffer from aperture envy like most other sky watchers.

 

After getting everything set up, collimated, etc. opened it to the Canada fire smoked & heavily light polluted night sky here in Saint Paul a few times. Prepared to be somewhat underwhelmed, lot's more stars popped up through the 20mm eyepiece! Put on a CLS filter and Yaaaaay! Even More! A bit puzzled why my super-wide field view was unfamiliar at Cassiopeia, I later made an eyepiece FOV mask transparency and laid it over the Sky Atlas. HaHaHaHaHa...re-calibrate your thinking, Mr. Astronomer!

 

Anyway, 1st post on CN; and I'm happy with the Comet Hunter. Shooting in daylight with the Canon T4i verified excellent sharp images. Looking forward to driving it out to some dark sky for some better views!


Edited by Drew57, 26 July 2015 - 10:29 PM.

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#57 Jarno

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Posted 26 July 2015 - 04:12 PM

Another 190MN owner here. I've done a side-by-side against my Vixen 102 fluorite (another scope that doesn't get the love it deserves BTW) and the view through the M-N is every bit as sharp and contrasty as the apo's but that's where the similarity ends. The M-N has 3.5 times the light grasp and 1.9 times the resolution so the Vixen is really out of it's league. A 6 or 7" apo will probably defeat the 190MN but at a price that's at least an order of magnitude higher. I've got a Losmandy plate on one side of the rings for mounting and a Vixen on the other side to use as an attachment point for the guide scope an  as a carrying handle. Lifting the scope onto the mount becomes a lot easier with such a handle because in my opinion it's not he weight of the scope that's causing problems, it's the bulk. You've got a large tube, heavy at both ends, and nothing to provide a good grip.

 

In a sense this is also the scopes weak point for imaging. Because of the long tube with the mass far from the middle it has a fairly large moment of inertia and you'll need a fairly beefy mount to hold it steady enough for imaging. In my experience the G-11 is pretty much the minimum needed if there's even a bit of wind. For this reason I ended up buying an Intes-Micro Alter M706, a 7" f/6 Mak-Cass. I've given up a bit of light grasp and contrast but have gotten a much more stable setup in return. While a 25mph wind doesn't bother the M706/G-11 combo in the slightest, the 190MN would be shaking pretty badly. Well, badly by imaging standards anyway, for visual use there wouldn't be any problem. The M706 has a moment of inertia that's about 1/4 of that of the M-N, is much easier to transport and put on the mount , and optical performance is only slighty less than the 190MN. For an SCT it's pretty much the same thing and although the difference in image quality will be much larger, most will still be very good performers.

 

So I guess that's why Mak-Newts aren't as popular as some people would expect. You have to make some considerable sacrifices to get that last bit of image quality and I'm guessing that most people willing and able to make those sacrifices will go for a refractor instead.

 

Jarno


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#58 kcb

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Posted 26 July 2015 - 10:06 PM

hi,

for maksutuv-newtonians i have the explore scientific comet hunter 150mm f4.8,reserved mostly for comets and wide field,refractor like but best at low powers for that focal ratio and an intes 127mm f/6 with low profile moonlite focuser,holds up well to my apo refractors,kevin

Edited by kcb, 26 July 2015 - 10:08 PM.


#59 Cotts

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Posted 27 July 2015 - 10:53 AM

I am the proud owner (3 weeks now...) of a Ceravolo HD 145 #0001.    I had first light at the Adirondack Astronomy Retreat a week and a half ago.  It is every bit the equal of a TEC 140 that I had recently.   Textbook perfect diffraction patterns, able to elongate 0.6" double stars, dark line split of 0.9" pairs.  Resolved a couple of dozen stars in M13.  Saturn was too low for a real test of the subtle contrast in the cloud bands (a real distinguishing test for contrast...).  I will have to wait for Jupiter to get up there this winter to really check the planetary contrast.  With a 16% central obstruction there is no way anyone could distinguish the diffraction pattern from that made by a fully unobstructed telescope.  Peter Ceravolo put his prodigious skill and experience into this scope and the HD 216 - I think it was such hard work that he did not make very many of either scope....

 

The tube only weighs 12 pounds.  With the supplied rings, dovetail and a dew heater it is about 15 pounds.  Much lighter than any 140-150mm class refractor...  

 

Here it is on the AVX mount.  A perfect match....   

 

IMG_7717.jpg

 

And, for use on my balcony, here it is riding in a Teeter STS Dob base that I had kicking around from an old project.  I can easily pick this entire thing up and tote it out to the balcony......

 

IMG_7777.jpg

 

This scope, like all others, has compromises:

 

1.  Wide field viewing with 35 Panoptic shows noticeable vignetting, the edge of the field being quite dark.   This effect is much less noticeable with a 24mm 68 degree eyepiece.  I'm looking for a 24 or 27 Panoptic as a result.  

 

2.  No photography.  Period.  The design is for 100% visual with the focal plane barely outside the tube.

 

3.. Some of my current eyepiece fleet don't reach focus.  Thankfully all Delos focus nicely.  I will use the 17.3 that I won at the TSP as well as newly ordered 12mm and 8mm.  Along with the 5 Nagler and 6-3 Zoom Nagler I have good eyepieces that work well.

 

4.  On an Equatorial mount rotating rings are required.  $450 !!!!  Gotta have them, though....

 

5.  cool down?  I do not want to compromise the originality of my #0001 scope as a collector piece so no add-on fans etc.  At Star Parties the scope will sit out all day and night under a reflective cover, following the daily temperature changes.  Winter on the balcony I'll just put it out a couple of hours before viewing time - should be ok....

 

But the advantages certainly outweigh them...

 

1.  Perfect, colour-free optics.  The field is flat to edge of a 17.3 Delos (1.4deg).  No coma, do diffraction spikes from a spider....

 

2.  light, easy to carry and mount.

 

3.  Permanent factory collimation....

 

4.  did I say perfect optics?

 

Dave


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#60 drollere

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Posted 27 July 2015 - 12:05 PM

they are all waiting for their scopes to cool down enough to be usable.



#61 bierbelly

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Posted 27 July 2015 - 12:41 PM

I am the proud owner (3 weeks now...) of a Ceravolo HD 145 #0001.    I had first light at the Adirondack Astronomy Retreat a week and a half ago.  It is every bit the equal of a TEC 140 that I had recently.   Textbook perfect diffraction patterns, able to elongate 0.6" double stars, dark line split of 0.9" pairs.  Resolved a couple of dozen stars in M13.  Saturn was too low for a real test of the subtle contrast in the cloud bands (a real distinguishing test for contrast...).  I will have to wait for Jupiter to get up there this winter to really check the planetary contrast.  With a 16% central obstruction there is no way anyone could distinguish the diffraction pattern from that made by a fully unobstructed telescope.  Peter Ceravolo put his prodigious skill and experience into this scope and the HD 216 - I think it was such hard work that he did not make very many of either scope....

 

The tube only weighs 12 pounds.  With the supplied rings, dovetail and a dew heater it is about 15 pounds.  Much lighter than any 140-150mm class refractor...  

 

Here it is on the AVX mount.  A perfect match....   

 

attachicon.gifIMG_7717.jpg

 

And, for use on my balcony, here it is riding in a Teeter STS Dob base that I had kicking around from an old project.  I can easily pick this entire thing up and tote it out to the balcony......

 

attachicon.gifIMG_7777.jpg

 

This scope, like all others, has compromises:

 

1.  Wide field viewing with 35 Panoptic shows noticeable vignetting, the edge of the field being quite dark.   This effect is much less noticeable with a 24mm 68 degree eyepiece.  I'm looking for a 24 or 27 Panoptic as a result.  

 

2.  No photography.  Period.  The design is for 100% visual with the focal plane barely outside the tube.

 

3.. Some of my current eyepiece fleet don't reach focus.  Thankfully all Delos focus nicely.  I will use the 17.3 that I won at the TSP as well as newly ordered 12mm and 8mm.  Along with the 5 Nagler and 6-3 Zoom Nagler I have good eyepieces that work well.

 

4.  On an Equatorial mount rotating rings are required.  $450 !!!!  Gotta have them, though....

 

5.  cool down?  I do not want to compromise the originality of my #0001 scope as a collector piece so no add-on fans etc.  At Star Parties the scope will sit out all day and night under a reflective cover, following the daily temperature changes.  Winter on the balcony I'll just put it out a couple of hours before viewing time - should be ok....

 

But the advantages certainly outweigh them...

 

1.  Perfect, colour-free optics.  The field is flat to edge of a 17.3 Delos (1.4deg).  No coma, do diffraction spikes from a spider....

 

2.  light, easy to carry and mount.

 

3.  Permanent factory collimation....

 

4.  did I say perfect optics?

 

Dave

David,

 

Assuming you'll need to order rotating rings, likely from Parallax, you should leave a little slop in the tube diameter measurement.  My Parallax rings are so precisely fitted to the tube of my Vega that I don't have any adjustment available, even though there are centering screws...which results in the goto's being off somewhat, since the tube is not perfectly aligned with the mount.  I've got to send them back and have a little machined out of the centers of the rings.  It's only been like, 5 or 10 years...


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#62 vahe

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Posted 27 July 2015 - 12:58 PM

2.  No photography.  Period.  The design is for 100% visual with the focal plane barely outside the tube.

3.. Some of my current eyepiece fleet don't reach focus.  

 

 

I am trying to read between the lines here, from your description do I correctly understand that with this MN binoviewers will not come to focus and therefore can not be used?

If that is the case then that is a major limitation of this MN’s visual use.
Speaking for myself that last time that I used a single eyepiece on a telescope was 21 years ago.

 

Vahe



#63 bierbelly

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Posted 27 July 2015 - 02:33 PM

Yeah, I think that binoviewers would be a problem, especially with rotating rings.  IMO, MNs are primarily visual instruments.  If you barlow it will throw the image plane away from the tube enough for imaging and likely enough for binoviewers, but of course then you lose the wide field, to some extent, and the rotational moment of the lever arm would be pretty high.


Edited by bierbelly, 27 July 2015 - 02:33 PM.


#64 Cotts

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Posted 27 July 2015 - 04:01 PM

 

2.  No photography.  Period.  The design is for 100% visual with the focal plane barely outside the tube.

3.. Some of my current eyepiece fleet don't reach focus.  

 

 

I am trying to read between the lines here, from your description do I correctly understand that with this MN binoviewers will not come to focus and therefore can not be used?

If that is the case then that is a major limitation of this MN’s visual use.
Speaking for myself that last time that I used a single eyepiece on a telescope was 21 years ago.

 

Vahe

 

Vahe, the focal plane is not far above the tube edge.  I tried to focus a Canon DSLR to infinity.  Not even close.  I tried a 2x Powermate.  Nope.  I also have a Denkmeier 1.3x OCS lens whose function is to bring the focus out further.  No luck there either.  I tried them both together.  No infinity focus....

 

I seriously doubt binoviewers will work in an HD 145 unless you want to look at flowers and bees a few metres away in your garden....

 

In fairness, Binoviewers were not on the market when Peter C. designed and built these scopes.  He went for state-of-the-art visual instruments for the 1990's.....

 

Dave



#65 Cotts

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Posted 27 July 2015 - 04:28 PM

 

 

2.  No photography.  Period.  The design is for 100% visual with the focal plane barely outside the tube.

3.. Some of my current eyepiece fleet don't reach focus.  

 

 

I am trying to read between the lines here, from your description do I correctly understand that with this MN binoviewers will not come to focus and therefore can not be used?

If that is the case then that is a major limitation of this MN’s visual use.
Speaking for myself that last time that I used a single eyepiece on a telescope was 21 years ago.

 

Vahe

 

Vahe, the focal plane is not far above the tube edge.  I tried to focus a Canon DSLR to infinity.  Not even close.  I tried a 2x Powermate.  Nope.  I also have a Denkmeier 1.3x OCS lens whose function is to bring the focus out further.  No luck there either.  I tried them both together.  No infinity focus....

 

I seriously doubt binoviewers will work in an HD 145 unless you want to look at flowers and bees a few metres away in your garden....

 

In fairness, Binoviewers were not on the market when Peter C. designed and built these scopes.  He went for state-of-the-art visual instruments for the 1990's.....

 

Dave

 

Further to the above.  Using a piece of translucent tape stretched across the eyepiece opening and viewing a smokestack about 10km away the focal plane is 36mm above the tube.  The focuser racked all the way in has a height of 26mm, giving 10mm of back focus.   Not even close to useful with a DSLR.

 

I have an eyepiece projection device which might work....

 

But I don't have a big desire to image with the HD 145 anyway...

 

Dave



#66 glend

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Posted 27 July 2015 - 05:53 PM

they are all waiting for their scopes to cool down enough to be usable.


Well this is a typical comment by mak-newt bigots. The truth is they are no worse than many designs and in some cases come equipped for active cooling - the Skywatcher MN190 has a fan port behind the mirror as one example. Even if not actively cooled they usually would not need much of a cool to ambient period.
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#67 Dwight J

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Posted 27 July 2015 - 07:04 PM

The Cerevolo that I have came with a fan behind the primary that threads on. There are vents around the meniscus for air to escape. Never had a problem with tube currents, etc. in terms of focal plane; I tried every which way to get a DSLR to focus (Barlow), taking everything out of the focuser and no go. CCD and planetary cameras worked very well except focusing them with the helical focuser was a bit of a pain. Mine is F5 and with a 22 Pantopic cruising the Milky Way is amazing. On planets the contrast and smooth optics combined with a night of good seeing will make you a believer.
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#68 wboeck

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Posted 09 August 2015 - 01:00 PM

I have an Orion Mak-Newt with the GSO type 2 speed focuser. Has anyone taken one apart to get it to work better? I tighten it but does not work the best. I have seen videos on Youtube showing how to take apart a GSO type focuser but my MN is not the same. It seems like a nice focuser but it needs some work.



#69 wboeck

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Posted 11 August 2015 - 07:57 PM

I finally got the focuser working. It is actually a Long Perng focuser. I took it apart similar to the Pollux Chung method. It did not need any cleaning or greasing or anything that is shown in the youtube video. After looking at how it was constructed, I figured that two screws that are not called out in the instructions needed loosening to allow the tightening plate to not restrict the barrel from traveling. It was a pretty easy adjustment but I could not find any documentation describing this. It works great! It easily lifts my DSLR and cooler and has lots of capacity.



#70 bierbelly

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Posted 09 September 2015 - 12:37 PM

 

I am the proud owner (3 weeks now...) of a Ceravolo HD 145 #0001.    I had first light at the Adirondack Astronomy Retreat a week and a half ago.  It is every bit the equal of a TEC 140 that I had recently.   Textbook perfect diffraction patterns, able to elongate 0.6" double stars, dark line split of 0.9" pairs.  Resolved a couple of dozen stars in M13.  Saturn was too low for a real test of the subtle contrast in the cloud bands (a real distinguishing test for contrast...).  I will have to wait for Jupiter to get up there this winter to really check the planetary contrast.  With a 16% central obstruction there is no way anyone could distinguish the diffraction pattern from that made by a fully unobstructed telescope.  Peter Ceravolo put his prodigious skill and experience into this scope and the HD 216 - I think it was such hard work that he did not make very many of either scope....

 

The tube only weighs 12 pounds.  With the supplied rings, dovetail and a dew heater it is about 15 pounds.  Much lighter than any 140-150mm class refractor...  

 

Here it is on the AVX mount.  A perfect match....   

 

attachicon.gifIMG_7717.jpg

 

And, for use on my balcony, here it is riding in a Teeter STS Dob base that I had kicking around from an old project.  I can easily pick this entire thing up and tote it out to the balcony......

 

attachicon.gifIMG_7777.jpg

 

This scope, like all others, has compromises:

 

1.  Wide field viewing with 35 Panoptic shows noticeable vignetting, the edge of the field being quite dark.   This effect is much less noticeable with a 24mm 68 degree eyepiece.  I'm looking for a 24 or 27 Panoptic as a result.  

 

2.  No photography.  Period.  The design is for 100% visual with the focal plane barely outside the tube.

 

3.. Some of my current eyepiece fleet don't reach focus.  Thankfully all Delos focus nicely.  I will use the 17.3 that I won at the TSP as well as newly ordered 12mm and 8mm.  Along with the 5 Nagler and 6-3 Zoom Nagler I have good eyepieces that work well.

 

4.  On an Equatorial mount rotating rings are required.  $450 !!!!  Gotta have them, though....

 

5.  cool down?  I do not want to compromise the originality of my #0001 scope as a collector piece so no add-on fans etc.  At Star Parties the scope will sit out all day and night under a reflective cover, following the daily temperature changes.  Winter on the balcony I'll just put it out a couple of hours before viewing time - should be ok....

 

But the advantages certainly outweigh them...

 

1.  Perfect, colour-free optics.  The field is flat to edge of a 17.3 Delos (1.4deg).  No coma, do diffraction spikes from a spider....

 

2.  light, easy to carry and mount.

 

3.  Permanent factory collimation....

 

4.  did I say perfect optics?

 

Dave

David,

 

Assuming you'll need to order rotating rings, likely from Parallax, you should leave a little slop in the tube diameter measurement.  My Parallax rings are so precisely fitted to the tube of my Vega that I don't have any adjustment available, even though there are centering screws...which results in the goto's being off somewhat, since the tube is not perfectly aligned with the mount.  I've got to send them back and have a little machined out of the centers of the rings.  It's only been like, 5 or 10 years...

 

BTW, after not having used my scope with the Parallax rings for several years, I had a chance to use it over the weekend.  I apologize for sort of badmouthing the Parallax rings.  After I looked closely at them, I realized that it was I who did not understand how to center the scope in the rings...the adjustment mechanism is built in, but I hadn't studied it enough to understand it...duh.  I performed just a seat of the pants centering adjustment, and the rings worked more than adequately, keeping the objects centered and maintaining good goto's during the entire observing session.

 

So bully to Parallax rotating rings.



#71 Drew57

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Posted 16 September 2015 - 11:13 PM

The Minnesota Mack-Newt and it's owner were up in Ely last weekend for darker skies. First night had long periods of clouds and limited viewing, but at least all the equipment worked well. Significant dew potential, but the Kendrick heater system worked very well on corrector and eyepiece. No issues at all with OTA cooling. Second night very clear. Definitely had to plan ahead where the scope would be pointing when positioning OTA in the cradle rings for a comfortable eyepiece location. The eyepieces are a bit heavy so minor issues with balancing/lever; I'll have to do something about that. 12V power distribution box made hooking up easy and all cables and deep-cycle battery out of the way under the tripod, so glad I took the time to make that.

 

Didn't take long to decide to stay with the 100o 20mm eyepiece for a while. Very high image quality with the ES Comet Hunter and ES eyepieces, I could find little to complain about. Some of the neighbors outdoor lights I could complain about. Skipped the go-to and used the finder scope to center Andromeda Galaxy. Absolutely beautiful...it filled the whole eyepiece! Amazing to look with naked eyes on the location, then through the eyepiece at 37X with a little 6" scope and see M31 revealed. I later viewed the Pleiades once it moved up from the horizon and it was loaded with stars like I've never seen. I can't imagine how great things must look through the big Dobs and SC's people have.

 

I think a Mack-Newt design like the Comet Hunter at f/4.8 is well suited for wide-field visual use, which is why I got it; but with some real dark sky it should do very well with the 9mm or 5.5mm eyepieces. It will be interesting to find how far magnification can be pumped up with good seeing. Going to have to look into a lower power even wider field eyepiece though; maybe an ES 83o 30mm...that is where this particular scope shines.

 

Was having too much fun just observing and did not do any prime-focus photography despite having a camera ready; but images I got of the recent blue moon show lot's of promise. The focal plane is close in the focuser, but works fine. BTW the Comet Hunter must be well sealed/baffled from stray light because daytime photography through it looks exceptional; it makes an excellent 731mm lens...try getting one of those for your DSLR for $800!



#72 George Kiger

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Posted 18 September 2015 - 09:45 AM

1.  Perfect, colour-free optics.  The field is flat to edge of a 17.3 Delos (1.4deg).  No coma, do diffraction spikes from a spider....

 

This design does have coma and a curved field, but if you don't see it who cares!?



#73 glend

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Posted 18 September 2015 - 07:33 PM

 

.... It will be interesting to find how far magnification can be pumped up with good seeing.

 

 

 

The Skywatcher MN190 can easily push to 500x (in the right seeing conditions obviously).


Edited by glend, 18 September 2015 - 07:33 PM.


#74 Drew57

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Posted 20 September 2015 - 03:43 PM

Did I inadvertently name my Mak-Newt "Mack?" ;) 

 

I did view through 100o 9mm and 5.5mm eyepieces and also both through a 2X focal extender...but it was looking at the recent blue moon. With CLS for contrast/cut back on junk light and polarizer to dial down brightness, there were some nice details on the moon; but I felt it was not a very good test.

 

With my present kit max magnification is 266X or 44X per inch of aperture. Back in the day I was enamored with University Optics HD Abbe Orthoscopics for simple 4-element design, etc., but as an eyeglass wearer eye relief is an issue. Maybe I should get contact lenses so planets and doubles or clusters can be explored better with the right eyepiece.

 

Thanks glend for reassurance, I'm just starting out and doing the wide-field thing, but eventually more has to be tried. I suppose sooner or later another scope is in order for some longer f/L and big aperture...



#75 bierbelly

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Posted 20 September 2015 - 04:57 PM

Did I inadvertently name my Mak-Newt "Mack?" ;)

I did view through 100o 9mm and 5.5mm eyepieces and also both through a 2X focal extender...but it was looking at the recent blue moon. With CLS for contrast/cut back on junk light and polarizer to dial down brightness, there were some nice details on the moon; but I felt it was not a very good test.

With my present kit max magnification is 266X or 44X per inch of aperture. Back in the day I was enamored with University Optics HD Abbe Orthoscopics for simple 4-element design, etc., but as an eyeglass wearer eye relief is an issue. Maybe I should get contact lenses so planets and doubles or clusters can be explored better with the right eyepiece.

Thanks glend for reassurance, I'm just starting out and doing the wide-field thing, but eventually more has to be tried. I suppose sooner or later another scope is in order for some longer f/L and big aperture...


Dont expect TOO much for high mag with an f/4. Orthos are ok for eyeglasses if you barlow. Invest in an OIII and go after the veil nebula right now!


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