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  #21  
Old 06-12-2018, 11:26 AM
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I don't think this is a shootout - moreso it seems Brian just enjoying himself observing.
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  #22  
Old 06-12-2018, 01:54 PM
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Hey Brian,

Keep going and do your own thing. Shootout or having fun is all the same in my book. In the past I did my own comparison between a 90x1000 achro and a Skywatcher ED 100. The ED was better but not by much so only wanting to keep one I sold the ED..... it was easy to sell

I知 very partial to long fl achros, as you know.
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  #23  
Old 06-12-2018, 08:25 PM
Joves (Aaron)
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Good stuff, looking forward to further reports!

If it turns out that the achro is the winner, i値l be going upstairs to my scope room with a very disappointed look on my face. I wont tell them they池e in trouble, i値l just tell them i知 disappointed in them (hey, works with the kids... apparently!).

Quote:
Originally Posted by brian nordstrom View Post
On going when I finish this current night shift stint ,,,, and when the weather clears up , Thanks .

Brian.
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  #24  
Old 06-12-2018, 09:10 PM
Wavytone (Nick)
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Quote:
Originally Posted by brian nordstrom View Post
When was the last time you viewed Sirius at 400x with a 102mm f10 achro
The first time was 45 years ago, through an 1880 Thomas Cooke 4.25" refractor, f/16 achro, with a truly exquisite objective. The views of Jupiter and Saturn through that scope are unforgettable. And it split Sirius, easily.

Ever since then I have been a high-magnification junkie mainly interested in lunar & planetary and to some extent double stars, as arguably the most severe optical test.

While I had access to the 9" Oddie refractor at Mt Stromlo - and pushed it to 900X while trying a few of the double stars in various catalogs and rapidly realised that in the 18th and 19th centuries, even though those old antique refractors were only 4" - 6" aperture:

a) didn't have modern glasses,
b) didn't have AR coatings,
c) had very limited eyepieces (try a Ramsden or Huygens and see how you feel about that)

... the records of the stars they were able to split indicate some of the scopes had truly exquisite objectives, even by modern standards.

Another clue lies in the notes from Dawes (the 'Dawes limit"), who concluded it is necessary to use magnification around 80X per inch to definitively split doubles at the limit of what the telescope can resolve. But for many modern refractors the useful limit is barely half that because the optics are frankly only "average", being designed to satisfy the シ wave criterion.

There really is a reason why premium old-school achro refractors were f/15-f/20, despite the massive equatorial mounting needed.

There really is a reason why people fork out $10k for an AP 130 GT. But aperture does rule and there are rare mythical beasts such as refractors with LZOS optics, or the premium big maks such as my MK91, or the TEC and AP 10" maks - if you can wait 20 years for one. The dinky little Takahashi's are toys in comparison.

Last edited by Wavytone; 06-12-2018 at 09:30 PM.
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  #25  
Old 06-12-2018, 09:29 PM
Joves (Aaron)
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Good write-up, Nick.

Now, what about my less mythical 8” Tec?


Quote:
Originally Posted by Wavytone View Post
The first time was 45 years ago, through an 1880 Thomas Cooke 4.25" refractor, f/16, with a truly exquisite objective. The views of Jupiter and Saturn through that scope are unforgettable. And it split Sirius, easily.

Ever since then I have been a high-magnification junkie mainly interested in lunar & planetary and to some extent double stars, as arguably the most severe optical test.

While I had access to the 9" Oddie refractor at Mt Stromlo - and pushed it to 900X while trying a few of the double stars in various catalogs and rapidly realised that in the 18th and 19th centuries, even though those old antique refractors were only 4" - 6" aperture:

a) didn't have modern glasses,
b) didn't have AR coatings,
c) had very limited eyepieces (try a Ramsden or Huygens and see how you feel about that)

... the records of the stars they were able to split indicate some of the scopes had truly exquisite objectives, even by modern standards.

Another clue lies in the notes from Dawes (the 'Dawes limit"), who concluded it is necessary to use magnification around 80X per inch to definitively split doubles at the limit of what the telescope can resolve. But for many modern refractors the useful limit is barely half that.

There really is a reason why old-school achro refractors were f/15-f/20, despite the massive equatorial mounting needed.

There is a reason why people fork out $10k for an AP 130 GT. But then there is something else ... the rare mythical beasts such as my MK91, or the TEC and AP 10" maks, if you can wait 20 years for one.

Last edited by Joves; 06-12-2018 at 09:46 PM.
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  #26  
Old 06-12-2018, 10:04 PM
Wavytone (Nick)
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Aaron, if you are keen on lunar & planetary or double stars it should be a keeper. Put yours side by side with a C8 or Meade 8" and try them side-by-side at high power (200-300X) on various targets. The difference should be obvious.

Santel closed 10 years ago, ditto Intes 2-3 years ago. TEC ceased making maks several years ago too, so like the MK91 only a small number were made, and you probably have the only one in Oz.

As for the AP 10" maks... the wait list is 25-30 years and they've just started to ship, slowly. IMHO the most likely way to acquire one would be one sold by a previous owner now in old age, ill heath or possibly a deceased estate.

These scopes are rare and I was surprised to hear Matt had parted with it, but perhaps he has other priorities.

What's more recent changes in the way freight carriers charge for shipping mean that importing a large scope from the US is now prohibitively expensive. And I mean that, literally.

Last edited by Wavytone; 06-12-2018 at 10:18 PM.
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  #27  
Old 06-12-2018, 11:23 PM
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Sweet Matt , this reminds me so much of the old days of CN's when the Purists (snobs) rallied against iStar , remember those days and they got shot down in the end ,,, history repeats .

Another instalment is on its way with more top quality photos taken with my cell phone ( CCD free zone ) and yes it would have been awesome to have an ED100 in this mix ( Tak free zone ) tho .

Thanks buddy , I am finding that a few ideal's here are starting to wear thin .

Brian
Quote:
Originally Posted by MattT View Post
Hey Brian,

Keep going and do your own thing. Shootout or having fun is all the same in my book. In the past I did my own comparison between a 90x1000 achro and a Skywatcher ED 100. The ED was better but not by much so only wanting to keep one I sold the ED..... it was easy to sell

I知 very partial to long fl achros, as you know.
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  #28  
Old 06-12-2018, 11:26 PM
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Nothing better to do brother .


When I ain't doing 12 hour night shift's 13 days on 1 off . Oh I am on the 14th day ( night ? ) , it gets hard .

Brian.
Quote:
Originally Posted by LewisM View Post
I don't think this is a shootout - moreso it seems Brian just enjoying himself observing.
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  #29  
Old 06-12-2018, 11:44 PM
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Ah well , looks like you can't wait until the end .

Comment's relevant to average 4 inch class refractors are more than welcome buddy .( 3-5 inch refractors as well )

Old school , yea they had ' Starbright ' coatings 75 years ago ? come on we have all seen that the coatings of today are 90% better than the old MgFl coatings of the 50's - 70's so why bother ???

FMC ?? another leap .

Brian.

ps.

ahhh well as you mention eyepieces ,, be-littleing H and R design's ? I have a 10 inch f10 Newtonion with easy 1/12 wave optics , My H6 .965 ( 416x ) shows Jupiter in this scope better than any modern eyepiece I have had the pleasure to put in this monster .
Quote:
Originally Posted by Wavytone View Post
The first time was 45 years ago, through an 1880 Thomas Cooke 4.25" refractor, f/16 achro, with a truly exquisite objective. The views of Jupiter and Saturn through that scope are unforgettable. And it split Sirius, easily.

Ever since then I have been a high-magnification junkie mainly interested in lunar & planetary and to some extent double stars, as arguably the most severe optical test.

While I had access to the 9" Oddie refractor at Mt Stromlo - and pushed it to 900X while trying a few of the double stars in various catalogs and rapidly realised that in the 18th and 19th centuries, even though those old antique refractors were only 4" - 6" aperture:

a) didn't have modern glasses,
b) didn't have AR coatings,
c) had very limited eyepieces (try a Ramsden or Huygens and see how you feel about that)

... the records of the stars they were able to split indicate some of the scopes had truly exquisite objectives, even by modern standards.

Another clue lies in the notes from Dawes (the 'Dawes limit"), who concluded it is necessary to use magnification around 80X per inch to definitively split doubles at the limit of what the telescope can resolve. But for many modern refractors the useful limit is barely half that because the optics are frankly only "average", being designed to satisfy the シ wave criterion.

There really is a reason why premium old-school achro refractors were f/15-f/20, despite the massive equatorial mounting needed.

There really is a reason why people fork out $10k for an AP 130 GT. But aperture does rule and there are rare mythical beasts such as refractors with LZOS optics, or the premium big maks such as my MK91, or the TEC and AP 10" maks - if you can wait 20 years for one. The dinky little Takahashi's are toys in comparison.
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  #30  
Old 07-12-2018, 12:05 AM
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This is a refractor 102-110mm shootout thread , please lets keep chit chat about Mak's out of it , thanks

Ahh well , well you guys are at hi-jacking my thread , here ! this a photo of my mates setting up their 20 inch PLUS Newt's , my 127mm iStar is all set up in the background ( we all arrived at this amazingly dark site together ) waiting for dark ,,, sound familiar ?


Brian.
Quote:
Originally Posted by Joves View Post
Good write-up, Nick.

Now, what about my less mythical 8” Tec?
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  #31  
Old 07-12-2018, 12:19 AM
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For the nay-sayers , this photo was taken looking 180 degrees from the last shot .


Refractors only please .

Brian.

Would I put the 127mm iStar on this shootout ? ..... No not fair ., but we did put my iStar 127mm and one of the 20inch + Dob owner's NP 127mm TV and a Meade 130mm triplet against each other on 3 occasion's and ,,, result's ,,, not here
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  #32  
Old 07-12-2018, 01:01 AM
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Ha ha , yes but as you know a lot depends on the eyepieces , family commitments , work , life , quality of seeing , eyepieces ( again ) , clouds , kid's , ( yep ) but yes if I won Lotto , you are invited to my observatory to use my SW ED 150mm its iOptron CEQ120 mount any time .

Brian .
Quote:
Originally Posted by Joves View Post
Good stuff, looking forward to further reports!

If it turns out that the achro is the winner, i値l be going upstairs to my scope room with a very disappointed look on my face. I wont tell them they池e in trouble, i値l just tell them i知 disappointed in them (hey, works with the kids... apparently!).
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  #33  
Old 07-12-2018, 09:22 AM
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I’ll be honest - when it comes to imaging, yes I am very particular (might say snobby) and even though I cannot even begin to bring out the best in the scope, knowing it’s me that is the limitation and not the optics is reassuring.

For visual, I love using achromats, especially Vixen 80Ms and Unitrons ( all the SW achromats I had have been very underperforming unfortunately - bad samples). One of my favourite visual scopes I have ever had was the Vixen FL102S semi-apo. Absolutely wonderful. A Tak FC60 f9 (not FS60) I had was also a favorite.

For lunar viewing, I could care less if there is a blue or yellow fringe on the limb - I’m looking at the surface for pities sake not the damned sky . Doesn’t distract me one zot.

Too many seem to be continually assessing and analyzing rather than actually using and observing.
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  #34  
Old 07-12-2018, 10:18 AM
N1 (Mirko)
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Quote:
Originally Posted by Wavytone View Post
There really is a reason why people fork out $10k for an AP 130 GT. But aperture does rule and there are rare mythical beasts such as refractors with LZOS optics, or the premium big maks such as my MK91, or the TEC and AP 10" maks - if you can wait 20 years for one. The dinky little Takahashi's are toys in comparison.
Sounds fantastic. Can we expect a link to a veritable test/shootout/comparo where one of these instruments beats an appropriately sized Mewlon by a margin sufficiently big for the latter to be called a toy?
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  #35  
Old 07-12-2018, 11:16 AM
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Quote:
Originally Posted by Wavytone View Post

There really is a reason why people fork out $10k for an AP 130 GT. But aperture does rule and there are rare mythical beasts such as refractors with LZOS optics, or the premium big maks such as my MK91, or the TEC and AP 10" maks - if you can wait 20 years for one. The dinky little Takahashi's are toys in comparison.
And yet, SOOOOOOOOOOOOOOOO many imagers worldwide us those dinky Takahashi toys to extremely good effect (prize winning), as well as those AP's. There is a definite, quantifiable reason WHY Taks and AP's are used.

Don't hear of too many Santel, Intes' or other Maks being used for fantastic imaging

Visual is FAR more forgiving than imaging.
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  #36  
Old 07-12-2018, 11:41 AM
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Even trying combos always surprises me. A SW 72ed with Tak diagonal and Toe 3.3mm and Vixen barlow easily split Eta Orionis 1.7"..very close to its Dawes(CHECK IT OUT)..in average seeing
only 10mins after set up.
I wait 20 mins longer for the 130mm Triplet CPC9,or 150 Mak..So CONVENIENCE TOO comes into it..lovely FAT AIRY disks in these small refractors..something I enjoy seeing..though I know the others will pull ahead later on!
At the end of the day its what YOU ENJOY!
PS: NOT into brands only PERFORMANCE!
bigjoe.
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  #37  
Old 07-12-2018, 12:12 PM
Kunama (Matt)
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I don't always agree with Mental-Alex but I do today, might be time to put the egos back in their cages and drift back onto the topic

I also like long achromats, I previously had a 6" F10 iStar and now have a nice 3.25" F15 that, given a modern eyepiece like a Tak LE, is a wonderful lunar scope.... I look forward to how these two scopes actually fare....
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  #38  
Old 07-12-2018, 12:28 PM
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I don't always agree with Mental-Alex but I do today, might be time to put the egos back in their cages and drift back onto the topic

I also like long achromats, I previously had a 6" F10 iStar and now have a nice 3.25" F15 that, given a modern eyepiece like a Tak LE, is a wonderful lunar scope.... I look forward to how these two scopes actually fare....
100% agree Matt
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  #39  
Old 07-12-2018, 05:56 PM
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h0ughy (David)
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OK I will say to all here on this post either keep it civil or you will have a nice long holiday. The mods have a life too and sometimes can't be every day reading the threads. If you can't be nice to each other then......
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  #40  
Old 08-12-2018, 12:21 AM
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IIS at it's best thanks brother.

For the know it all's , achro or apo ? a hint here what refractor ? touching 150x , dark for a few that know better .

Brian.
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OK I will say to all here on this post either keep it civil or you will have a nice long holiday. The mods have a life too and sometimes can't be every day reading the threads. If you can't be nice to each other then......
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