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Hello! i am seeking the help of those with experience in refractors please!!

I have been an amateur since i was just a wee lad, i have always owned catadioptric and reflectors of many types, unfortunately short of my current Lunt LS60PT and the department store pea shooter i had as a 12 year old and my which spent way more time peering through windows in the apartment complex across the street than gazing at the sky i have NO experience with refractors. 

This is where forums like this come in, ok this is what id like to do, my budget is around US1,200, for this i would be looking at a doublet no doubt, i would like it to be in the F5-F7 range? this would offer some flexibility for both visual and future basic AP dabbling.

I mainly would like this refractor for planetary, lunar and double star observing, i do hear that nothing beats a refractor for these objects and I'm itching to see for myself.

I realize that this budget will not get me an NP101 or any other triplet for that matter, but i would like the best for that price in the 100mm range preferably since id love to stretch its legs on lunar and planetary. i also own a 12" lightbridge but this is definitely not a grab and go scope which is what id love to have now, CA would be an issue not so much for visual but future photo work id like something that performs reasonably well in the CA department. 

if anyone out there has had much experience with refractors id love to hear from you! 

Thank you all!!!

 

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Very nice to see different people have different approaches.

For planetary i am planning to get SCT or reflector no doubt, even a dobsonian will be my choice, i will never chose a refractor for planetary even if it can do the job, and for now i m settling on 11" decision, for planetary regardless about the seeing conditions, all told me it is the long what you need, and i doubt you can have in refractor, even if you do it will be very very expensive refractor, but you may be lucky and get one that will do the job for you.

My talk is about AP, observing is different story, i can't help in that, but i hope you won't get disappointed with something for observing to use in AP, and to my thinking and i could be wrong, if the scope is great for AP then it is great for observing, or should it be the opposite?

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As you mentio the AP side get one of the ES triplets. ED doublests sound good but they are a doublet and therein can show CA which on imaging is certainly what you do not want. They are also a good price.

Baically get a triplet.

If imaging is going to be a factor then I suggest something around the 100-102mm diameter. Not sure if $1200 would make it to one of the FCD-100's.

The 127 above sounds nice but will eventually need a good mount, and size is not necessarily best for imaging, geneally good for visual but visual criteria do not apply to imaging. Hence my suggestion of the 100mm area.

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Can you confirm what sort of imaging you intend to do in future? There is a big difference between lunar and planetary imaging and Deep Sky/long exposure imaging.

For lunar/planetary observing the Skywatcher 100mm f9 scopes are very nice, even the 120ED would be worth considering. Visually a good doublet is great, cools down quickly. Either of these would probably still work well for imaging of the same targets, but if you mean to do Deep Sky imaging then they are likely too slow/long focal length to be optimal. In this case, an 80ED is often suggested as a starter scope.

So, if you confirm what your imaging aspiration are then advice may differ accordingly.

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A rough guide seems to be:- Planetary  = Large and Slow 

                                           Deep Sky   = Small and Fast

I think it is going to be tough to do both well within the budget.  :icon_biggrin:

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I'd suggest looking into an achromatic refractor - not just the much more expensive APO's and ED refractors. The much-maligned Achromatic's were the only type of refractor in existence when refractors got their high marks for planetary work, splitting tight double-stars, and other amazing feats.

Sure - there may be some purple-blue around bright objects, but hey - filters can reduce such if it's a problem. And for AP, it can be removed during processing.

I love my achro's!

Dave

 

5a017b6a38c9d_ST80ClubT-Shirta.jpg.49b28736615203c8a95e1406cb4cf117.jpg

 

Edited by Dave In Vermont
sp.
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I should just point out that considerable controversy reigns over what design of telescope, and what aperture, is best for planetary observing. The subject has been aired previously in these forums.  Some say APOs, some say SCTs. Some say Maks. Others say long-focal ratio Newtonians are good.  

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3 minutes ago, Cosmic Geoff said:

I should just point out that considerable controversy reigns over what design of telescope, and what aperture, is best for planetary observing. The subject has been aired previously in these forums.  Some say APOs, some say SCTs. Some say Maks. Others say long-focal ratio Newtonians are good.  

That is a very good point Geoff.

I have found that a good 4" refractor is capable of showing lovely, stable images of planets which allow you to draw out a surprising amount of detail. At high powers, excellent optics hold up where others go soft, but the small exit pupils needed can cause problems with floater visibility.

Larger aperture scopes certainly can show more detail and colour, the limiting factor is often the atmospheric conditions. SCTs and Maks are very effective if cooling and collimation (particularly for SCTs) is spot on. A good 16" Newt will show wonderful planetary images in good conditions, but if seeing is variable then you have to wait longer for the moments when the image stabilises and the detail shows through. I see more with a large scope but enjoy observing more with a 4" frac. Add that to the portability and it is a highly attractive package, provided you understand it cannot defy the laws of physics :) 

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14 hours ago, Sunshine said:

planetary, lunar and double star observing

 

6 hours ago, Dave In Vermont said:

I'd suggest looking into an achromatic refractor

+1. This one, a 102 f13 has an excellent goto mount and no false colour. They also do a 102 f10 whopping 127 f10 all of which fall into budget. HTH.

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23 hours ago, Sunshine said:

i also own a 12" lightbridge but this is definitely not a grab and go scope which is what id love to have now

Just as a data point, cut a four to five inch off axis mask from card stock for your Dob and tape it to the front of your Dob so that the hole is between vanes.  Voila!  You now have a four to five inch unobstructed apochromatic telescope!  See what planets, the moon, and doubles look like through it.  Then try smaller masks such as a three inch to see what size frac meets your minimum requirements.  It's a lot cheaper than buying multiple APOs to decide what size suits your needs.

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Thanks to everyone for all the amazing info and tips, in the end i decided after a lot of reading and asking around that the best bang for the buck both in aperture and optical performance all around would be 

the Skywatcher 150 Mak cassegrain. I believe it would be the closest ill get to a 4 inch triplet without getting well out of the grab and go range, as for astrophotography I'm aware of its 1800mm focal length and being an F12 yes its slower than

molasses but again, I'm willing to hold off on the AP for a bit. Right now i need something that i can easily keep covered in my garage to maintain temp and run outside with or throw in car (not literally throw) without carrying my 12" Dob downstairs and fiddling with knobs and trusses, my Dob i love for planned dark sky excursions well away from light polluted skies where i happen to live. 

the skywatcher 150 Mak is no slouch optically and inch per inch under light polluted skies i think it will be perfect, my dob swallows a lot of starlight and equal amounts of streetlight lol

now some of you may be saying "ahhh i told him to get the 3 inch triplet" haha i wish i could run down the list of scopes you all replied with and tell my local store to order them all please, i went from asking about refractor help to buying a Maksutov

thats the beauty about our great hobby, the choices are endless and sometimes you want this today and end up walking out of the store with something completely different, sorry if some of you feel i may have wasted your time but yesterday i too was sold on a refractor. thanks to all of you!!

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Unless going to do 8 hour exposures, when AP, then doublet is the way to go

Advantage of a doublet over a triplet, especially where you live in Canada, doublet cools down lot quicker than a triplet

Triplet can also be front heavy depending on the type of mount you are using

Can also get a filter for either to enable solar viewing

Have enclosed pic of my Skywatcher ED80 with solar filter on a EQ5 mount 

Cheers

John

 

Skywatcher ED80.jpg

Edited by cletrac1922
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14 hours ago, Sunshine said:

the Skywatcher 150 Mak cassegrain. I believe it would be the closest ill get to a 4 inch triplet without getting well out of the grab and go range, as for astrophotography I'm aware of its 1800mm focal length and being an F12 yes its slower than

molasses but again, I'm willing to hold off on the AP for a bit. Right now i need something that i can easily keep covered in my garage to maintain temp and run outside with or throw in car (not literally throw) without carrying my 12" Dob downstairs and fiddling with knobs and trusses, my Dob i love for planned dark sky excursions well away from light polluted skies where i happen to live. 

the skywatcher 150 Mak is no slouch optically and inch per inch under light polluted skies i think it will be perfect, my dob swallows a lot of starlight and equal amounts of streetlight lol

now some of you may be saying "ahhh i told him to get the 3 inch triplet" haha i wish i could run down the list of scopes you all replied with and tell my local store to order them all please, i went from asking about refractor help to buying a Maksutov

My grab and go is a DSV-2B alt-az mount with an AT72ED on one side and a 127mm Mak on the other for many of the same reasons you outlined above.  You could add a 3" or so ED doublet refractor for wide field views and later use it with a field flattener on an EQ mount for decent AP.  I don't know what sort of mount you're interested in using to start with, but I almost bought a 127mm Mak on an EQ3 type of mount until I went to pick it up to move it to a better observing location and was shocked at how heavy it was with counterweights.  The legs were aluminum, but those counterweights torpedoed the deal.  My back simply couldn't take it.

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