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Equipment Discussions >> Refractors

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Sean Puett
Carpal Tunnel
*****

Reged: 09/06/10

Loc: always cloudy, washington
Re: Achro Vs Apo new [Re: timps]
      #5755659 - 03/25/13 08:28 AM

Quote:

Maybe I should go down the Newtonian reflector path?
Long FL with high quality optics and it would be on par with a large aperture Apo for a fraction of the cost.




I am not trying to convince you to buy a newtonian. That is where my big aperture money goes. What I think you should do is go to a star party or astronomy club and try them all before deciding. I get great planetary views with my dob. One of the local CNers has a Webster d14 and Jupiter is amazing through that scope. The d series scopes have Zambuto mirrors.
Try as many scopes as possible so you don't judge a poorly collimated scope of the type you may prefer. I like having the ability to collimate my own scopes so that may be something to ask about when you are trying these out. This "what type of telescope should I buy?" type thread are really only so helpful because you may have far different ideas of what a "great view" or "planetary detail" means. How many times have you read something like, "my new 4-5" apo blew away a 12"+ newtonian." my mass produced newtonian shows the bands on Jupiter as very dark and detailed, when I have good skies. My 4" refractor (which is admittedly not a planetary scope) shows that Jupiter is round and shows the two large belts but not as detailed.
The point of this is just for you to be careful how much stock you put in the opinions expressed here and on other websites. If you can't try the different scopes before you buy, try buying used. Then if it doesn't live up to expectations, you may only be out the shipping costs. Although it is very possible to find deals where you pay far less than a scope is worth. You have time to do research and get the right scope so take your time and you will end up much happier with the results.


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buddyjesus
Carpal Tunnel
*****

Reged: 07/07/10

Loc: Davison, Michigan
Re: Achro Vs Apo new [Re: t.r.]
      #5755671 - 03/25/13 08:40 AM

cooling times is the big difference besides resolution. Refractors and reflectors both complement each other nicely.

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galaxyman
Vendor - Have a Stellar Birthday
*****

Reged: 04/04/05

Loc: Limerick, Pa
Re: Achro Vs Apo new [Re: De Lorme]
      #5755725 - 03/25/13 09:37 AM

Quote:

Sean, in theory I agree with you it does not matter. But
Convience is not a theory. When you have rool off roof
it's just so much easier. No wasted time. No limitations
on which scope to buy or set up. I've seen mabey 2 large refractors {8"}and 1 8" lens up for sale in the last 5 years. I look every day.D&G and Istar are still in buisness.
Karl, I'm thinking a 8"F/6 would ride fine on my CGEM.
1.Tub weights 10.75lbs. ,2. lens 10.25klbs. 4.rings weight aprox. 10lbs 4. lenght is no longer than a AT 10" reflector{which rode well on top of my CGEM} and smaller in diameter.
I"ve never looked through a 8" so being an fast f/6 would I be able to use enough power to bring in and thus resolve
gobular clusters? What do you think? De Lorme




Yes, for the 7.1" achro is an f/6, and I've seen through the scope numerous times. The owner ( a highly respected DSO observer and owner of a multitude of scopes large and small) has pushed the scope well over 300x with great results on globs, smaller galaxies and planetary nebula. It actually gave a nice view of Saturn with using some high-end orthos.

The owner has seen galaxies down to at least 14th mag, so the scope does quite well in the DSO realm, and the wide-field views using the Ethos eyepieces are terrific. My larger 8" goes even deeper. You can see and hear in the Galaxy Log series plus the blog, for many of my mid-size scope galaxy observations are with the 6" and 8" refractors.



Karl
E.O.H.


Chesmont Astronomical Society - www.chesmontastro.org
Galaxy Log - http://www.youtube.com/user/GalaxyLog4565?feature=mhee
Galaxy Log Blog - http://galaxylog.blogspot.com/
HASB - http://www.haveastellarbirthday.com
Telekit (Swayze optics) 22" F/4.5 Dob
Homemade (Parks Optics) 12.5" F/4.8 Dob
TMB/APM 8" f/9 Refractor”The Beast”. One great DEEP SKY achro
ES 6" f/6.5 achro. Good one
Celestron Omni XLT 102 refractor.
Celestron 10x60mm Binos


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Gord
Carpal Tunnel
*****

Reged: 01/06/04

Loc: Toronto, ON, Canada
Re: Achro Vs Apo new [Re: De Lorme]
      #5755797 - 03/25/13 10:14 AM

Quote:

Because it's not primarily about just the view. Comfort and
ease of use are equally as important. A 8" F/8.8 achro refractor lens from Istar is about $1700. I would say a 16"
reflector mirror would be about a 1/3 more. The aproximate
total weight on putting a 8"F/6 on my CGEM is around 32lbs
with a length of 48" for about $2500. How much does a goto
trackimg system for a large reflector cost. About the same
or a little more than a CGEM-DX. But which one is more difficult to use. The reflector.
Reflectors you have to collimate accurately.
You have to install fans to get them to ambeint tempertures
You have to wait until cooled.
You have to stand on a stool or ladder to view.
Have to buy a coma corrector
Eyepieces cost considerably more
Large refractors take a lot more time to set up
Refractors have none of these problems.
One thing I will say though with Orion making large goto dobs cheaper than a large refractor that might make a differance initially. But I believe in the long run the extra cost to be able to sit and not have the other issues
will be worth it. People really do not consider convience
until they experience not having it. De Lorme




De Lorme,

Different people will find different things comfortable, but for myself, I'm with you on the seated observing position being the best. One below/behind the OTA ideally as you can get a comfortable seated position with a dob (smaller sizes) as well. With the tracking capabilities that they have now (dobs), it's really almost as good as the refractor/CAT's except for having to watch for thermals.

However, I think it's worth pointing out some issues with your statements around a large achro refractor being the only/best way to go. They have most of the issues you point to in the reflectors and other scopes:

-thermals, refractors are affected by these as well, especially so in larger sizes. At 6", the effect is there already (although still the best of all the designs) and from what I understand, by 10" they are becoming as bothersome as in other designs

-EP's & correctors, this is really dependent on the f-ratio. An F6 refractor is going to have as many issues as an F6 reflector. Aberrations are there in most designs and it's more about picking your poison and having the ability to work around it. In this regard, the refractors are likely worst (ie. CA). The ARIES Chromacor is an incredible tool for fixing this, but not as available as say a coma corrector for a newt and doesn't ultimately give you as perfect of overall result either (Chromacor corrects only the on-axis field). If you look at something like the Edge HD's from Celestron, they are already corrected and essentially perfect out of the box

-Setup/teardown of a large refractor --- NO! No advantage for the refractor, in fact quite the opposite! They are the worst of the bunch! Speaking from personal experience, I can say that the 6" refractor and the C14 are essentially equal in terms of effort. I'll call the OTA's a draw since the C14 is heavier and more compact, and the refractor is lighter, but longer. At 8", the refractor is a BEAST!

-The 8" F6 refractor you mention --- This is still a large scope (worse than the two I mention just above), but there's a real kicker to it: only good as a low power sweeper at 50x max magnification (per IStar's recommendations). I'm sure it would work ok at 100x, but this is in no way comparable to any other reflector out there. Every one of them will slaughter this thing in every way except for what it was purpose built to do (very low power sweeping of star fields). 100x is just getting going in most scopes of this size, and higher powers are really needed to get to the most details.

I can give you some personal experience with a bunch of different designs and how they compare. The 6" refractor can almost show as much as the C8 SCT on some objects (DSO's) and does better in a few cases (widest possible FOV and the contrast shown in that case). As soon as the FOV get's down to 1-deg or so, I find the C8 has the edge. For planetary, it's all C8. I got a chance to test a Chromacor and that is giving indications that it may level the field for planetary, but I need to get the two side-by-side.

The 10" newt is ahead of both the refractor and C8 on everything except widest FOV possible. The C14 is ahead of everything else (by a good bit...) except widest FOV.

To give you an idea of how far ahead the C14 is, the best view of a globular in the 6" refractor (M13) is what many of the less showcase globular's in the sky look like in the C14. Color in all objects is much more distinct. I have observed some of the globular clusters *in* M31 with the C14 from my backyard in the city. I've tried this with the 10" newt from the same conditions and came up short.

While I'm sure the 8" refractor (the longer ones) are going to do more than the 6" refractor, it comes at a cost (in various forms...) and will at best match up to a good 10" newt in some ways, but won't match bigger reflectors.

Clear skies,


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galaxyman
Vendor - Have a Stellar Birthday
*****

Reged: 04/04/05

Loc: Limerick, Pa
Re: Achro Vs Apo new [Re: Gord]
      #5755841 - 03/25/13 10:32 AM

Hmm? Interesting that a scope of the same f/6, and only 0.9" larger would have such issues going much beyond 12x per inch of aperture, whereas the scope I describe above has no problem with over 40x per inch of aperture on the objects mentioned.

Karl
E.O.H.


Chesmont Astronomical Society - www.chesmontastro.org
Galaxy Log - http://www.youtube.com/user/GalaxyLog4565?feature=mhee
Galaxy Log Blog - http://galaxylog.blogspot.com/
HASB - http://www.haveastellarbirthday.com
Telekit (Swayze optics) 22" F/4.5 Dob
Homemade (Parks Optics) 12.5" F/4.8 Dob
TMB/APM 8" f/9 Refractor”The Beast”. One great DEEP SKY achro
ES 6" f/6.5 achro. Good one
Celestron Omni XLT 102 refractor.
Celestron 10x60mm Binos


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Gord
Carpal Tunnel
*****

Reged: 01/06/04

Loc: Toronto, ON, Canada
Re: Achro Vs Apo new [Re: galaxyman]
      #5755868 - 03/25/13 10:45 AM

Hi Karl,

I know what you mean, but I expect there are a few things at play:

1. they are playing it extremely safe, although I know when you get into the design edge cases like these a slight variation in quality can have a big (negative) effect. Which leads to #2...

2. the bigger objectives are harder to make (good) and they don't have a lot of control over this since things are outsourced and built to a price point. The APM's like yours and the one you mention are made in China as well, but Markus has gotten out of this business due to the problems with trying to keep the quality high enough. His prices are higher just because he has to deal with the rejects to get a decent product.

So if you take a quality version of these like what Markus was offering, I think you get more and can go higher.

Clear skies,


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galaxyman
Vendor - Have a Stellar Birthday
*****

Reged: 04/04/05

Loc: Limerick, Pa
Re: Achro Vs Apo new [Re: Gord]
      #5755896 - 03/25/13 10:59 AM

Hi Gord

Possible, and I think he still sells the 8" f/9

I though would love to see through one of the Istar's 8" scopes, and see what it can do under a good dark sky.

I've read some good things about their scopes so far, and I see you have a 6".

Karl
E.O.H.


Chesmont Astronomical Society - www.chesmontastro.org
Galaxy Log - http://www.youtube.com/user/GalaxyLog4565?feature=mhee
Galaxy Log Blog - http://galaxylog.blogspot.com/
HASB - http://www.haveastellarbirthday.com
Telekit (Swayze optics) 22" F/4.5 Dob
Homemade (Parks Optics) 12.5" F/4.8 Dob
TMB/APM 8" f/9 Refractor”The Beast”. One great DEEP SKY achro
ES 6" f/6.5 achro. Good one
Celestron Omni XLT 102 refractor.
Celestron 10x60mm Binos


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jrbarnett
Eyepiece Hooligan
*****

Reged: 02/28/06

Loc: Petaluma, CA
Re: Achro Vs Apo new [Re: timps]
      #5755908 - 03/25/13 11:03 AM

Problem with Newtonians is that the eyepiece is at the wrong end of the telescope.

- Jim


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Ed Holland
Pooh-Bah


Reged: 06/16/10

Loc: San Jose, CA and Oxford, UK
Re: Achro Vs Apo new [Re: jrbarnett]
      #5756109 - 03/25/13 12:38 PM


The importance of Achro Vs. Apo also depends on ones's experience level and enthusiasm for the hobby. Get a decent achro, and a beginner or budget minded person* can enjoy an awful lot of viewing and learning. For visual, I frequently find that the weakest link in the optical path is our atmosphere, and that my slightly aberrated (is that a word?) 5" Achro rarely gets a chance to reach maximum performance, and is perfectly adequate to my needs.

Would I like an Apo? of course, but can't justify it for the type of viewing I do, or the amount of time I have available.

*or a grumpy tightwad, like me


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Eddgie
Postmaster
*****

Reged: 02/01/06

Re: Achro Vs Apo new [Re: galaxyman]
      #5756138 - 03/25/13 12:49 PM

Quote:

Well maybe because they have actually had great views with them? Unless you think they are all full of it?




In fact, I had a premium 6" f/8 acromat custom made for me about 10 years ago.

While the optical quality was superb, the scope was not partitularly satisfying as a planetary scope.

Long focal lenghts do improve, but do not eliminate the damage done by the CA.

And if you can get the same contrast performacne out of an MN66, why would you want a 6" f/15 achromat?

To reduce the CA to the level that the contrast transfer is better than an MN66, the focal lenght would be better at f/18 for the 6" refractor.

And even the 6" APO does not "blow my socks off" for planets. I routinely see much more in my C14.

I have had better planetary observing out of a number of larger reflectors.

The best planetary views I have ever had were when viewing though someone elses premium mirror 12" f/5 reflector with boundry layer fans (see, you don't have to wait more than 30 seconds to get perfect views, so cool down is not an issue unless you allow it to be) and premium (Zambuto) mirrors.

I have never seen a view with any scope bigger, smaller, obstructed, unobstruted, or polka dotts as I have seen in that scope.

But the premium 6" f/8 achromat was not the answer for me. My C14 is easily far better than that scope was for planets, and it was carfully designed to give as good aplaneatry performance as possible at f/8.

I sold it. No magic there for me.

In fact, the Meade 152ED f/9 I owned was better by a long strecth.


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Gord
Carpal Tunnel
*****

Reged: 01/06/04

Loc: Toronto, ON, Canada
Re: Achro Vs Apo new [Re: galaxyman]
      #5756145 - 03/25/13 12:52 PM

Quote:

Hi Gord

Possible, and I think he still sells the 8" f/9

I though would love to see through one of the Istar's 8" scopes, and see what it can do under a good dark sky.

I've read some good things about their scopes so far, and I see you have a 6".

Karl
E.O.H.





Hi Karl,

Markus has the 8" F9 still listed, but I don't know if he is offering them any more. He said he wasn't when I contacted him about them and the reason gave was what I mentioned above (in terms of quality variation). He only want's to attach his name to quality optics so isn't willing to send out sub-par samples (which is good to hear!). He said some would be really great, and others terrible.

Unfortunately, I haven't been able to see what my current lineup are like under really dark skies. Life at the moment has me tied to my backyard so all of my comparisons are done from there.

The 6" classic IStar achro I have is a nice lens. I have got into testing optics more lately and I can now see it isn't perfect, but at the same time it appears to be in line with what they were originally spec'd at for these ones (about 1/5 wave). These were really good value, but I'd say they are now just good value as the prices have gone up. I don't think the R-series are so good in value since they cost significantly more than the classics and they aren't any better in terms of spec. Their OTA's are extremely well built with the only downside being the weight.

Clear skies,


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Eddgie
Postmaster
*****

Reged: 02/01/06

Re: Achro Vs Apo new [Re: mark8888]
      #5756165 - 03/25/13 01:02 PM

Quote:

is there any advantage in getting a large APO as opposed to a reflector (of any size)? A large APO,




A quick story. About 8 years ago, I got in a very public debate with Roland Christen because I was very critical of the long wait list for a 155mm refractor. (Actually my grip was more to do with the black hole that is the AP notification process. For the full five years I was on the list, I never heard a peep from AP, which to me indicated blatent disregard for the potential customer).

During the course of this dialog, I had mentioned that I wanted the best planetary scope I could find.

He was quick and to the point in his response, and that response was essentially this (I am paraphrasing):

"Oh, well, if that is all you want, get a really good 10" f/6 reflector. That will be a better planetary scope than the 155EDF. These scopes are really best as astrographs."

Mr Christen I belive prefers his 10" MCT as a planetary scope over his own APOs.

But then again, Mr Christen used to use a C8 from time to time, so maybe he was not sure what he was talking about because OMG, who would want a C8?


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galaxyman
Vendor - Have a Stellar Birthday
*****

Reged: 04/04/05

Loc: Limerick, Pa
Re: Achro Vs Apo new [Re: Eddgie]
      #5756203 - 03/25/13 01:41 PM

Quote:

Quote:

Well maybe because they have actually had great views with them? Unless you think they are all full of it?




In fact, I had a premium 6" f/8 acromat custom made for me about 10 years ago.

While the optical quality was superb, the scope was not partitularly satisfying as a planetary scope.

Long focal lenghts do improve, but do not eliminate the damage done by the CA.

And if you can get the same contrast performacne out of an MN66, why would you want a 6" f/15 achromat?

To reduce the CA to the level that the contrast transfer is better than an MN66, the focal lenght would be better at f/18 for the 6" refractor.

And even the 6" APO does not "blow my socks off" for planets. I routinely see much more in my C14.

I have had better planetary observing out of a number of larger reflectors.

The best planetary views I have ever had were when viewing though someone elses premium mirror 12" f/5 reflector with boundry layer fans (see, you don't have to wait more than 30 seconds to get perfect views, so cool down is not an issue unless you allow it to be) and premium (Zambuto) mirrors.

I have never seen a view with any scope bigger, smaller, obstructed, unobstruted, or polka dotts as I have seen in that scope.

But the premium 6" f/8 achromat was not the answer for me. My C14 is easily far better than that scope was for planets, and it was carfully designed to give as good aplaneatry performance as possible at f/8.

I sold it. No magic there for me.

In fact, the Meade 152ED f/9 I owned was better by a long strecth.




Hi Ed

I agree, and though I don't observe planets, I've seen how well a great 12.5" reflector does on planets (say like Saturn) for I have one.

I'm a DSO observer, and yes here the larger dob like my 22" is my deep deep scope. The large quality refractors give me a different perspective here, and give the most aesthetic views. In fact in some way these views make up for lack of aperture to the larger dob. I know, for I had both the 8" refractor and the 22" dob (wonderful Swayze optics and Spectrum Max R coatings) side by side on a terrific night at our darkest local (within 2 hour drive) site.

Using very similar magnifications, the big 8" refractor was certainly holding its own for its aperture (wife did some drawings), and even showing a 15th mag galaxy.

Inch for inch I'll take the refractor here, though yes the larger scope of high quality is hard to beat.


Karl
E.O.H.


Chesmont Astronomical Society - www.chesmontastro.org
Galaxy Log - http://www.youtube.com/user/GalaxyLog4565?feature=mhee
Galaxy Log Blog - http://galaxylog.blogspot.com/
HASB - http://www.haveastellarbirthday.com
Telekit (Swayze optics) 22" F/4.5 Dob
Homemade (Parks Optics) 12.5" F/4.8 Dob
TMB/APM 8" f/9 Refractor”The Beast”. One great DEEP SKY achro
ES 6" f/6.5 achro. Good one
Celestron Omni XLT 102 refractor.
Celestron 10x60mm Binos


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galaxyman
Vendor - Have a Stellar Birthday
*****

Reged: 04/04/05

Loc: Limerick, Pa
Re: Achro Vs Apo new [Re: Gord]
      #5756224 - 03/25/13 01:54 PM

Quote:

Quote:

Hi Gord

Possible, and I think he still sells the 8" f/9

I though would love to see through one of the Istar's 8" scopes, and see what it can do under a good dark sky.

I've read some good things about their scopes so far, and I see you have a 6".

Karl
E.O.H.





Hi Karl,

Markus has the 8" F9 still listed, but I don't know if he is offering them any more. He said he wasn't when I contacted him about them and the reason gave was what I mentioned above (in terms of quality variation). He only want's to attach his name to quality optics so isn't willing to send out sub-par samples (which is good to hear!). He said some would be really great, and others terrible.

Unfortunately, I haven't been able to see what my current lineup are like under really dark skies. Life at the moment has me tied to my backyard so all of my comparisons are done from there.

The 6" classic IStar achro I have is a nice lens. I have got into testing optics more lately and I can now see it isn't perfect, but at the same time it appears to be in line with what they were originally spec'd at for these ones (about 1/5 wave). These were really good value, but I'd say they are now just good value as the prices have gone up. I don't think the R-series are so good in value since they cost significantly more than the classics and they aren't any better in terms of spec. Their OTA's are extremely well built with the only downside being the weight.

Clear skies,




Hi Gord

Interesting and glad I got a great one

Well I hope you can get back out to darker sites, for a good 6" refractor can be lots of fun under clear dark skies.

I see ISTAR is going to be at NEAF, so I'll definitely check them out.


Karl
E.O.H.


Chesmont Astronomical Society - www.chesmontastro.org
Galaxy Log - http://www.youtube.com/user/GalaxyLog4565?feature=mhee
Galaxy Log Blog - http://galaxylog.blogspot.com/
HASB - http://www.haveastellarbirthday.com
Telekit (Swayze optics) 22" F/4.5 Dob
Homemade (Parks Optics) 12.5" F/4.8 Dob
TMB/APM 8" f/9 Refractor”The Beast”. One great DEEP SKY achro
ES 6" f/6.5 achro. Good one
Celestron Omni XLT 102 refractor.
Celestron 10x60mm Binos


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De Lorme
professor emeritus
*****

Reged: 12/30/08

Re: Achro Vs Apo new [Re: galaxyman]
      #5756295 - 03/25/13 02:30 PM

As I said before It's not only about the view.
My AT 10" reflector was good. But I had to continulaly rotate the tube to see. Collimate, allow to cool,buy a coma corrector and STAND all the time.
I keep seeing big dobs up for sale here on CN. Why?
Because after a while the body says Not gonna do this no more!LOL I have no doubts that a BIG dob gives great views.
But the convience factor slowly takes over. I have read many
times, the best scope is the one that you use. It is so true. If it Just sits there because of the sheer {bulk}hassle to deal with you end up selling it and getting a refracter. My first telescope was a Meade 10" cat. I could
not sit and look with it either. So good buy Cat.
Please don't take this like your dobs or cats are junk. Thier not.
People don't think about comfort and convience until they
do not have it. Would you rather go to work in a Dodge Ram
in the middle of the winter with no heat or go to work in Dodge Dart with heat? Keep Looking up, De Lorme


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t.r.
Post Laureate
*****

Reged: 02/14/08

Loc: Upstate NY
Re: Achro Vs Apo new [Re: De Lorme]
      #5756391 - 03/25/13 03:13 PM

Quote:

Mr Christen I belive prefers his 10" MCT as a planetary scope over his own APOs.




In the Florida Keys, at the winter star party yes...at home in the typical seeing conditions in the northern part of the country, no. And he has said as much. That is the only point you forget to address Eddgie...not everyone has your SouthWest seeing conditions and climate. In many parts of the country a puny 5" refractor will surpass that 14 SCT on planetary aesthetics. Fact. My 5" apo beat a Cave 16" newt and got a star parties "Best view on the field award" looking at Jupiter. It can and does happen, albeit usually only North of the Mason-Dixon line!


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mark8888
Carpal Tunnel


Reged: 09/24/10

Re: Achro Vs Apo new [Re: t.r.]
      #5756439 - 03/25/13 03:32 PM

Quote:

Quote:

Mr Christen I belive prefers his 10" MCT as a planetary scope over his own APOs.




In the Florida Keys, at the winter star party yes...at home in the typical seeing conditions in the northern part of the country, no. And he has said as much. That is the only point you forget to address Eddgie...not everyone has your SouthWest seeing conditions and climate. In many parts of the country a pultry 5" refractor will surpass that 14 SCT on planetary aesthetics. Fact. My 5" apo beat a Cave 16" newt and got a star parties "Best view on the field award" looking at Jupiter. It can and does happen, usually only North of the Mason-Dixon line!




If you google image search: Cave 16" newt

you get a funny mix of images. I'm not sure if any of them are a Cave 16" newt though.

In any event, I'm wondering... OK, so if you use a C14, a big dob, Cave 16" newt, in a place with poor seeing in the north for example... what exactly do you see most of the time? Basically a jumbled up mess that only very occasionally clears up and shows a lot of detail, and then goes back to the mess?

A scope with how many inches of aperture used at a place with poor seeing creates an almost-always unstable image? In other words, how many inches is the maximum at which one can expect a decent image a lot of the time at a place with generally not very good seeing?



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t.r.
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Reged: 02/14/08

Loc: Upstate NY
Re: Achro Vs Apo new [Re: mark8888]
      #5756472 - 03/25/13 03:48 PM

This may give you an idea...in NY, in a large aperture scope (+10")this would be considered a fairly descent/average view. However, look closely, there is no N or S hemisphere detail(spots,belts,mottling,gradation), no detail within the belts, no clearly defined edges to belts, zones, etc. This really isn't that a great a view, but all the macro detail is there. What is lacking is the micro details which really make for a fine view. The image is also not stable, shimmering, jumping around and soft. But for many, this is indeed a "good" view!

http://www.youtube.com/watch?v=5p_Wx-0HYNs



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dan_h
Carpal Tunnel


Reged: 12/10/07

Re: Achro Vs Apo new [Re: mark8888]
      #5756508 - 03/25/13 04:13 PM

<< What exactly do you see most of the time? Basically a jumbled up mess that only very occasionally clears up and shows a lot of detail, and then goes back to the mess? >>

No. It never clears up. At least not around here in the winter time.

I think part of the reason there is such a gap between the points of view expressed on these forums is because many folks don't appreciate the vast differences in viewing conditions that prevail in different areas. I have been to WSP and seen some marvelous views. I have been in the mountains outside Tuscon where you can see forever. I have also lived most of my life in the area north and east of the Great Lakes where seeing is typically bad to horrible (and that's when the jet stream isn't messing things up.)

dan


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Lane
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Reged: 11/19/07

Loc: Frisco, Texas
Re: Achro Vs Apo [Re: jrbarnett]
      #5756628 - 03/25/13 05:15 PM

Quote:

Problem with Newtonians is that the eyepiece is at the wrong end of the telescope.

- Jim




But you buy one of those special newts like they use in the Little Ceasar's commercial, they seem to have solved that problem.


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