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Old 28-03-2020, 08:17 AM
TareqPhoto (Tareq)
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Thinking about a scope ... or just to wait???

Hi all,

It is really so bad and difficult in this time with many issues and crisis all around and with very tight budget or so bad financial situations, making all kind of decisions like a "Mission Impossible".

So, i am still thinking and thinking and thinking and came up with those which are maybe not yet the last plan, but at least i narrowed it down to that, so if you have to choose or go with one of the following regardless if you may change later, what will you get really [with reasons if possible please]???



1. 12" F4 Newtonian [for planetary imaging only]

2. Two 150mm [6"] F4 Newtonian [DSO imaging]

3. Two 130mm F5 Newtonian [DSO]

4. Cheap cheap affordable doublet semi APO or ED refractor [DSO]

5. 0.73x reducer for 200mm [8"] F5 Newtonian [DSO imaging]



All above are for imaging only, i have 8" F5 and i have a mono cooled camera [QHY163M] and filters, so it is only about telescopes now, i am still not using my 8" F5, but i know even before i use it that it won't fit all targets in my mind, it will do nice job for small targets anyway, but i feel like i still prefer a wide field more, and i won't get SCT or triplet refractor, so only above are my very soon choices, otherwise i just stop AP and keep waiting to save and go with high end or larger scopes within my maximum saving after 1 year or two, i have a plan to buy a high end expensive refractor so any those affordable triplets are out of my plan and mind, and SCT is so so much expensive than Newtonian or Dobsonian so i won't waste money on that, also i don't want SCT just it can do DSO and planetary because that is requiring extra accessories and also more expensive to be honest, just before going SCT or triplet route discuss why any of above isn't a good idea to think about.

Any further details you need i am willing to answer, and remember, it is not yet confirmed or as a final plan, but i want to think about it as i have to decide on a telescope within April/May to start.
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  #2  
Old 28-03-2020, 08:21 AM
Imme (Jon)
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Save your money and buy a good telescope.
No use wasting savings on something just for the sales off spending money.
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  #3  
Old 28-03-2020, 08:23 AM
TareqPhoto (Tareq)
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Quote:
Originally Posted by Imme View Post
Save your money and buy a good telescope.
No use wasting savings on something just for the sales off spending money.
Waiting is applicable and i am still waiting since 2018, but sounds i may wait much longer this time, so i will miss many imaging opportunities then? Will you miss that in order to save and get a nice scope at the end?
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Old 28-03-2020, 10:21 AM
sunslayr (David)
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It's always a good idea to play to the strengths of a telescope, I would not get the 0.73x reducer you will probably find you end up with an unsatisfactory image on newer cmos cameras that have smaller pixels like the qhy163m. If you have a limited budget and still want a wide field, an ed doublet is a really good choice especially if you are shooting in mono. You are already set with your 200mm F5, that will handle most DSO targets, more if you create mosaics, also planetary with a 2-4x barlow. You might find many scopes arriving on the used market with the economy the way it is.
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Old 28-03-2020, 10:49 AM
glend (Glen)
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Tareq, honestly there is nothing wrong with an 8" f5 Newt for imaging. Learn the craft on that before you go adding to the collection. For DSOs you will need a good coma corrector, like a Baader MPCC mk3, and I assume you have an adequate mount. For planetary you will need to look at a Parracor etc to get you the necessary focal length multiplier.
If your heart is set on a good triplet APO, don't compromise with cheaper colour handiacaped Doublet refractors, ED or not all Doublet are compromised.Your Newt has no colour issues, keep that in mind.
Good luck.
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Old 28-03-2020, 11:03 AM
TareqPhoto (Tareq)
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Originally Posted by sunslayr View Post
It's always a good idea to play to the strengths of a telescope, I would not get the 0.73x reducer you will probably find you end up with an unsatisfactory image on newer cmos cameras that have smaller pixels like the qhy163m. If you have a limited budget and still want a wide field, an ed doublet is a really good choice especially if you are shooting in mono. You are already set with your 200mm F5, that will handle most DSO targets, more if you create mosaics, also planetary with a 2-4x barlow. You might find many scopes arriving on the used market with the economy the way it is.
In fact i also have DSLR lenses, Canon to be specific, including 300mm f2.8IS a prime, and Canon 135mm F2, 85mm f1.8, 70-200 f2.8IS markII and few more, so i also play with those for wide field, but sounds in many posts around in forums or Facebook groups it sounds that a telescope is still superior to a lens, so i was thinking to stay at wide field, somewhere between 400mm or 500mm up to 700mm only, and a reducer will bring my 8" F5 to something like 730mm F3.65, not sure if that is any good or not, but from those FoV calculator sites i find out that something like 500-600mm is enough until i can afford high end for wider, and the only Newt i can think about in this range is 6" F4 itself, but when i gave few choices i found out people only choosing either 130mm F5 or 150mm F5 instead of 150mm F4, is that because all or most of them are scared to collimate F4 or they think it is too wide for their tastes?
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Old 28-03-2020, 11:19 AM
TareqPhoto (Tareq)
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Quote:
Originally Posted by glend View Post
Tareq, honestly there is nothing wrong with an 8" f5 Newt for imaging. Learn the craft on that before you go adding to the collection. For DSOs you will need a good coma corrector, like a Baader MPCC mk3, and I assume you have an adequate mount. For planetary you will need to look at a Parracor etc to get you the necessary focal length multiplier.
If your heart is set on a good triplet APO, don't compromise with cheaper colour handiacaped Doublet refractors, ED or not all Doublet are compromised.Your Newt has no colour issues, keep that in mind.
Good luck.
I have to explain or clarify some points for you to be more clear about it:

1. I do have a corrector, Skywatcher F4 Aplanatic, i can get Paracorr but not now, not yet.

2. I tried 2x and 5x Powermates with my Newt and it didn't work, i couldn't get to the focus at all, either with extensions which is making it worse or without extensions, my focuser isn't a low profile and i didn't buy one, i only replaced the stock focuser single speed to a dual speed Crayford, it works without any Barlow or extender, many told me to move the mirror, this is not gonna happen as i tried moving the primary mirror a bit to maximum and didn't work, so i will never drill it to move the secondary, i will keep it for DSO only then, and i always and forever wanting larger than 8" for planetary no matter what.

3. I got this 8" F5 brand new as cheap last piece, for distant galaxies and some clusters, so i don't need to push it for another targets and then i will be forced to surgery my scope, i am willing to buy another one, not giving this 8" F5 which i didn't use yet, but for some targets mainly those in Cygnus i need to go wider than 1000mm, even wider than 700-800mm, so that i asked about something like 6" F4 which gives ~600mm, nice for QHY163M, i even can buy two because i am still planning to buy another CMOS 16mm mono camera but maybe ASI1600mm this time to accommodate my high quality 1.25" filters better than QHY163M.

4. I included a very cheap doublet only because i don't want to regret it once i buy a Takahashi scope, it is in my plan or wishlist and i will never stop saving for it even for long time, so it means any cheap APO as triplet will be a waste and a lose if i buy a Tak later, some told me buy now and sell later, i have so so many items lying around waiting to be sold and they aren't sold yet, so i will never make this mistake again, if i want a Tak then i better go directly to the Tak even if i save for years, so in this case it is either very cheap doublet less than $500 or none until i buy a Tak, and you know any doublet less than $500 brand new it won't be that great and it will show color issues somehow although many said with NB it is not a big deal, so what about getting three achromatic refractor then and use different NB filter with each or even each has RGB filter individually and each will be focused individually?

I am open to more opinions and suggestions, but i have my own plans that i try not regret later, i have different situations and mind than others, many are willing to buy cheap or used, i try to avoid that except something cheap that can last longer and i don't need to get rid of it if i upgrade, for example i have a 7" Mak, amazing for the moon and not bad for planetary, but i will never use it for planetary forever as i don't like the results while others liked mine a lot, but i will not throw it if i buy a larger scope for planetary, it is still nice for the moon, or if i want a wide view of planets to show moons sometimes, but if i have a Tak FSQ, no APO triplet/doublet will see the light again then.

Not very rush of the above options, but since last 2 yeas i ended up with scopes issues only, i mean it is time for me to update my scopes collection, one for DSO and one for planetary, and i already did research and it sounds my options are very tight due to my current budget mainly and my future plan also.
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  #8  
Old 28-03-2020, 01:13 PM
sunslayr (David)
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If your heart's really set on a Tak, then I'd keep saving. For me I found that my SW Esprit 100 is more than enough. It strikes a balance between price, aperture and portability with comparable performance to a Tak (Comparison). I guess If i were to upgrade I'd go with something like a Tele Vue-NP101 for a flat visual field or maybe something a little bigger. Have a look around on reviews and astro-bin maybe something like a SW 120ED could suit you has a 765mm focal length with the reducer, I'd doubt you would have trouble selling it.
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Old 28-03-2020, 01:56 PM
TareqPhoto (Tareq)
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Quote:
Originally Posted by sunslayr View Post
If your heart's really set on a Tak, then I'd keep saving. For me I found that my SW Esprit 100 is more than enough. It strikes a balance between price, aperture and portability with comparable performance to a Tak (Comparison). I guess If i were to upgrade I'd go with something like a Tele Vue-NP101 for a flat visual field or maybe something a little bigger. Have a look around on reviews and astro-bin maybe something like a SW 120ED could suit you has a 765mm focal length with the reducer, I'd doubt you would have trouble selling it.
Maybe, you are right, but since let's say 2018 i keep reading all around and it all leads to high end such as AP or Takahashi or even TEC140 which is also nice popular high end scope, but i made my mind on one thing so i keep that and try not to change it to save for it, i saw the Esprit examples and i read about people reviews or impressions about it, but i saw few who upgraded from Esprit or Stellarvue or WO for example to Takahashi or TEC, so that was enough for me to know that people are moving from great to superior, why don't i want a superior high class then if i can save and afford later?!!!

For now, i still can use my lenses, and my 8" F5 Newt, and i can buy more Newt as i don't need to get rid of Newt really even if i have high end refractors, a Newt is a different type, but i feel like they are less wanted over another types such as refractor or SCT, so i am still not sure if going with another Newt can be a good idea or not, and i also mentioned about cheap doublet that is maybe semi APO, but sounds even this is not a nice choice by many, it is either a great triplet or SCT or high end Newt or RC, i feel like i have no choice but the least voted ones.
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Old 28-03-2020, 02:07 PM
sunslayr (David)
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If you want a Newt then don't let me stop you, they are a fine choice for AP the only downside with a small fast newtonian is the collimation and the central obstruction.
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Old 28-03-2020, 02:29 PM
TareqPhoto (Tareq)
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Originally Posted by sunslayr View Post
If you want a Newt then don't let me stop you, they are a fine choice for AP the only downside with a small fast newtonian is the collimation and the central obstruction.
1. Collimation, how to solve or deal with that? Collimator? i have 3, is that enough?

2. Central obstruction, what does this do to the final image? spikes? I don't mind spikes, if something else then what else?

I don't have to go with a Newt as a must if it has some issues people don't like, i just added to the list because i saw enough great results out of Newtonian and they are cheap some of them, i mean i can get for example 6"-8" in same price of 4"-5" refractor or even cheaper, and it doesn't have colors issue, but i feel like i am moving in a closed circle, many go with a triplet or APO refr and i try not go with that because of high end saving, and if i go with the Newt i will feel like people will blame or believe that i will only face issues and headache or i won't get nice results, i really feel i am lost or i feel like i don't want to do anything, coming from photography and what i spent in the past really did a bad negative attitude on me, so that i feel like i will never buy anything in astro until i am 1000% sure, not just follow all people whatever they choose and regret later.
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Old 28-03-2020, 03:32 PM
sunslayr (David)
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I can definitely understand where you are coming from, it can quickly become overwhelming with all the different options. Its a bit like asking what car should I buy? Like cars all telescopes have advantages and disadvantages there is no one size fits all 'best telescope'.

I the case of an imaging newtonian Everything must be perfectly in line to achieve the best results, this is can be a little difficult for a beginner which is why people often recommend a refractor (Link to Astrobaby's guide). Not only does something like an F4 Newt require precise collomation but the focuser also has to be stiff enough to handle the precision involved and can often require and upgrade to something like a moonlite focuser which can add to the cost.

The central obstruction in a newtonian is the the secondary mirror that reflects the image from the primary into the camera or eye through the focuser. This 'obstruction' blocks some of the light and makes the image dimmer and reduces contrast.

Now normally a newt is large enough to compensate for this but If you want a wider field you start hitting the limit of what can be achieved by going faster with a reasonable price so you have to go smaller say 150mm F4. However while at 200mm the secondary taking up around 35% of the total aperture, at 150mm it is taking up almost 47%. That is why people avoid small imaging newtonians because a refractor is a more efficient at gathering light at those sizes.

Hopefully that helps a little.
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Old 28-03-2020, 03:39 PM
glend (Glen)
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It sounds to me like your Newt is not an imaging newt, as you cannot focus a camera. The focal point of a camera will be inside the focal point of a typical visual Newt.
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Old 28-03-2020, 04:00 PM
Startrek (Martin)
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Hi Tareq,
I’ve been imaging with a GSO 6” f6 newt and a GSO 8” f5 newt for some time now just using a 9 year old Canon 600D APS-C sensor and can image most objects in the night sky ( excluding wide field Nebula )
I also do planetary imaging with the same scopes using BYEOS and Televue powermates with my DSLR

I don’t know what all the fuss is about
6” f6 newt cost me $299
8” f5 newt cost me $470
Canon 600D was my wife’s old camera which she never used
I use low end Skywatcher HEQ5 and EQ6-R mounts
PHD2 guiding
Collimation is really easy after you have done it a few times ( takes 5 minutes )
Image scale is around 0.80 arc sec per pixel
Here are just some objects I can fit in my FOV with both scopes -
M42 Orion
Lagoon Nebula
Trifold Nebula
60% Carina Nebula
Omega Nebula
Tarantula Nebula
All globular clusters obviously
Rosette Nebula
Jewel box
All galaxies
Most open clusters
And the list goes on and on

Here are some of my images with these newts in both Bortle 8 and Bortle 3 skies
I also have a 12” Goto dob newt for observing
Hope this information helps you in some way
Martin
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  #15  
Old 28-03-2020, 05:00 PM
JA
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Quote:
Originally Posted by TareqPhoto View Post
1. Collimation, how to solve or deal with that? Collimator? i have 3, is that enough?

2. Central obstruction, what does this do to the final image? spikes? I don't mind spikes, if something else then what else?

I don't have to go with a Newt as a must if it has some issues people don't like, i just added to the list because i saw enough great results out of Newtonian and they are cheap some of them, i mean i can get for example 6"-8" in same price of 4"-5" refractor or even cheaper, and it doesn't have colors issue, but i feel like i am moving in a closed circle, many go with a triplet or APO refr and i try not go with that because of high end saving, and if i go with the Newt i will feel like people will blame or believe that i will only face issues and headache or i won't get nice results, i really feel i am lost or i feel like i don't want to do anything, coming from photography and what i spent in the past really did a bad negative attitude on me, so that i feel like i will never buy anything in astro until i am 1000% sure, not just follow all people whatever they choose and regret later.
Any action no matter how poorly conceived, if boldy executed is better than inaction.....

Not my words BTW, but something I try to use in life

Best
JA
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Old 28-03-2020, 09:44 PM
Hemi
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Quote:
Originally Posted by JA View Post
Any action no matter how poorly conceived, if boldy executed is better than inaction.....

Not my words BTW, but something I try to use in life

Best
JA
Nice saying JA, but I’m not sure if I agree with it, or disagree. But a wise Greek physician also said.....FIRST do no harm

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Old 29-03-2020, 02:12 AM
TareqPhoto (Tareq)
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Quote:
Originally Posted by sunslayr View Post
I can definitely understand where you are coming from, it can quickly become overwhelming with all the different options. Its a bit like asking what car should I buy? Like cars all telescopes have advantages and disadvantages there is no one size fits all 'best telescope'.

I the case of an imaging newtonian Everything must be perfectly in line to achieve the best results, this is can be a little difficult for a beginner which is why people often recommend a refractor (Link to Astrobaby's guide). Not only does something like an F4 Newt require precise collomation but the focuser also has to be stiff enough to handle the precision involved and can often require and upgrade to something like a moonlite focuser which can add to the cost.

The central obstruction in a newtonian is the the secondary mirror that reflects the image from the primary into the camera or eye through the focuser. This 'obstruction' blocks some of the light and makes the image dimmer and reduces contrast.

Now normally a newt is large enough to compensate for this but If you want a wider field you start hitting the limit of what can be achieved by going faster with a reasonable price so you have to go smaller say 150mm F4. However while at 200mm the secondary taking up around 35% of the total aperture, at 150mm it is taking up almost 47%. That is why people avoid small imaging newtonians because a refractor is a more efficient at gathering light at those sizes.

Hopefully that helps a little.
I see, that is an excellent answer and explanation, now i know about those small Newtonian, thank you very much
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Old 29-03-2020, 02:15 AM
TareqPhoto (Tareq)
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Originally Posted by glend View Post
It sounds to me like your Newt is not an imaging newt, as you cannot focus a camera. The focal point of a camera will be inside the focal point of a typical visual Newt.
I think maybe that is true, although i tried to image and i could image M42 and the moon with it, but sounds it is not designed to take extensions or Barlow and such, but i have to give it another try to see, for me if it focus without those then that is fine and enough for me, some told me to go with a low profile focuser, i just don't want to buy a focuser that will force me to drill the scope body or have to move the secondary mirror.
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Old 29-03-2020, 02:20 AM
TareqPhoto (Tareq)
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Quote:
Originally Posted by Startrek View Post
Hi Tareq,
I’ve been imaging with a GSO 6” f6 newt and a GSO 8” f5 newt for some time now just using a 9 year old Canon 600D APS-C sensor and can image most objects in the night sky ( excluding wide field Nebula )
I also do planetary imaging with the same scopes using BYEOS and Televue powermates with my DSLR

I don’t know what all the fuss is about
6” f6 newt cost me $299
8” f5 newt cost me $470
Canon 600D was my wife’s old camera which she never used
I use low end Skywatcher HEQ5 and EQ6-R mounts
PHD2 guiding
Collimation is really easy after you have done it a few times ( takes 5 minutes )
Image scale is around 0.80 arc sec per pixel
Here are just some objects I can fit in my FOV with both scopes -
M42 Orion
Lagoon Nebula
Trifold Nebula
60% Carina Nebula
Omega Nebula
Tarantula Nebula
All globular clusters obviously
Rosette Nebula
Jewel box
All galaxies
Most open clusters
And the list goes on and on

Here are some of my images with these newts in both Bortle 8 and Bortle 3 skies
I also have a 12” Goto dob newt for observing
Hope this information helps you in some way
Martin
Very nice images or results, that is why i try not giving up with Newtonian, i can collimate my 8" F5 easy, i tried it several times and it became just fine and not an issue, the only issue if i move to faster Newt or if i buy a reducer to convert my F5 to faster one, so does collimation become more difficult going faster?

How do you rate your 12" Dob? Can you use it for imaging also mainly planetary? I don't like to do planets with scopes less than 10", even 10" i see it less because i already saw results from something like 12" and 14" up to 1 meter, so it printed in my mind that i will never buy any scope less than 12" for planetary, i do have 7" Mak for that and my 8" F5 and i still want much more and longer for planet, so i don't need to stop going larger for that, 2 years is enough for me to know and decide how large, but i can't go with SCT because they are more expensive than Newt for same exact aperture, i mean even 8" SCT is much more expensive than 8" or 10" Newtonian.
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  #20  
Old 29-03-2020, 02:21 AM
TareqPhoto (Tareq)
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Quote:
Originally Posted by JA View Post
Any action no matter how poorly conceived, if boldy executed is better than inaction.....

Not my words BTW, but something I try to use in life

Best
JA
That is tooo risky my friend
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