20 replies to this topic

[jml79]

It's time for a bigger scope. I have 76mm triplet, 102mm doublet and 8" f/4 Newt and I am building a new observatory this summer with enough room for 3-4 rigs (tightly packed in). I have a budget of around $3000 CDN for a larger scope. I know it isn't a huge amount but it's enough to have a few options. I have a QHY294M with filter wheel and an OAG on the shelf waiting for a new scope and an EQ8. So big pixels and big mount, I am not worried about size or portability. Here are what I have found in my price range. I don't have a good OSC camera so Hyperstar isn't a big consideration right now but it is a nice option to have down the road.

 

-Celestron C8, Starizona 0.63 reducer and Hyperstar. This is the lightweight budget option and I should be able to afford all of it at once but I am not that thrilled with the 400mm focal length when in hyperstar mode.

-Celestron Edge 800 and Celestron reducer.

*Celestron C9.25, Starizona 0.63 reducer. This is what I am leaning towards. It's about the same focal length as the Edge 8 with the starizona reducer but a bit faster and the hyperstar is a much nicer 525mm f/l if I go that route.

-TS-Optics UNC 300mm (12") f/4 Newt. This is the big light bucket but it's about the same price as the C9.25 or Edge 8. Slightly wider FOV than either of those with their reducers and no hyperstar but it's a 12" f/4 light bucket. Sampling wise it sits in a very happy place of 0.79 which from experience matches my seeing almost perfectly and I have an IMX571 if I want to sample tighter.

 

Tell me why I am crazy and what your experiences are with any of these combos.

 

Thanks.

[airscottdenning]

I've been imaging with a C8 EdgeHD for about 5 years and I love it. I retrofitted it with a Moonlite CHL focuser on the back because I can't get repeatable autofocus with the moving mirror. I just lock the mirror down and focus with the big CHL.

 

I did buy the Celestron reducer and a Hyperstar but I almost never use them. The stars are not nearly as good with either one compared to the native f/11 and for short focal lengths I just prefer a refractor.

 

DSO images at f/11 (2100 mm) require patience, an OAG, and a good mount. 

 

Lunar and planetary with the C8Edge are surprisingly good. 

 

PN and galaxy images with this rig are wonderful, and about as high resolution as I'm ever likely to get due to my poor seeing in the immediate lee of the Rocky Mountains.

[KGoodwin]

The Starizona LF reducer is, I think, a better solution than an Edge HD with the Edge reducer.  The Edge reducers are just not amazing.  At full focal length the Edge spots are quite decent, but with a reducer they degrade to the point where I think you're better off with the non-edge scope and the Starizona LF reducer.

 

https://starizona.co...-coma-corrector

 

It's only for the 11" and 14" scopes.  A used model would probably be in your budget, at least for the 11".  I think the non-edge 11" model doesn't have mirror locks, whereas the non-edge 14" model I think does.

[happylimpet]

I have an EQ8 in an obsy. It carries either a 16" f4 (£1500) or a 12" f5 (£250) , both with ease. Go large, capture light, smile. I know I do. Im imaging Mars and smiling right now!

Edited by happylimpet, 24 April 2025 - 04:52 PM.

[jmillsbss]

It's time for a bigger scope. I have 76mm triplet, 102mm doublet and 8" f/4 Newt and I am building a new observatory this summer with enough room for 3-4 rigs (tightly packed in). I have a budget of around $3000 CDN for a larger scope. I know it isn't a huge amount but it's enough to have a few options. I have a QHY294M with filter wheel and an OAG on the shelf waiting for a new scope and an EQ8. So big pixels and big mount, I am not worried about size or portability. Here are what I have found in my price range. I don't have a good OSC camera so Hyperstar isn't a big consideration right now but it is a nice option to have down the road.

 

-Celestron C8, Starizona 0.63 reducer and Hyperstar. This is the lightweight budget option and I should be able to afford all of it at once but I am not that thrilled with the 400mm focal length when in hyperstar mode.

-Celestron Edge 800 and Celestron reducer.

*Celestron C9.25, Starizona 0.63 reducer. This is what I am leaning towards. It's about the same focal length as the Edge 8 with the starizona reducer but a bit faster and the hyperstar is a much nicer 525mm f/l if I go that route.

-TS-Optics UNC 300mm (12") f/4 Newt. This is the big light bucket but it's about the same price as the C9.25 or Edge 8. Slightly wider FOV than either of those with their reducers and no hyperstar but it's a 12" f/4 light bucket. Sampling wise it sits in a very happy place of 0.79 which from experience matches my seeing almost perfectly and I have an IMX571 if I want to sample tighter.

 

Tell me why I am crazy and what your experiences are with any of these combos.

 

Thanks.

My home skies are good at best. On top of that, I don't have many nights where all the pieces of weather, skies and life all fall into place and I get to get out under the stars. This was the main reason I built the ROR obsy.  Everything is sitting there, ready to go at a moments notice.  I may get an hour here, an hour there, two hours one night, 4 the next.  This is the main reason, and I also meant to get a capable mount that could manage large aperture and fast scopes.  Enter the G11.  So, I have the C8 Hyperstar as my wide-field nebula buster and for a little longer focal length I have the 10" F4 Newt.  I'm very well pleased with the both of them and if one could build and run an observatory, I wouldn't expect to put a 3" refractor in it as my main scope. Go big and fast.  That's just me right now...

[happylimpet]

My home skies are good at best. On top of that, I don't have many nights where all the pieces of weather, skies and life all fall into place and I get to get out under the stars. This was the main reason I built the ROR obsy.  Everything is sitting there, ready to go at a moments notice.  I may get an hour here, an hour there, two hours one night, 4 the next.  This is the main reason, and I also meant to get a capable mount that could manage large aperture and fast scopes.  Enter the G11.  So, I have the C8 Hyperstar as my wide-field nebula buster and for a little longer focal length I have the 10" F4 Newt.  I'm very well pleased with the both of them and if one could build and run an observatory, I wouldn't expect to put a 3" refractor in it as my main scope. Go big and fast.  That's just me right now...

Thats exactly my situation, except my skies are worse than average at best. Big aperture is amazing for planets and pulling in the faint galaxy light through the light pollution, any chance I get.

[jmillsbss]

Thats exactly my situation, except my skies are worse than average at best. Big aperture is amazing for planets and pulling in the faint galaxy light through the light pollution, any chance I get.

I know, not everyone can do it, but when I look at some of my 10 minute galaxy images I KNOW I couldn't get that SNR with the 3" APO.  I'd love to get a big ol' RC and start imaging galaxy clusters in the nether regions but that ain't happening, just looking through this bright mud puddle of a sky that I'm working with!

[GaryShaw]

Hi Joe

I have an 8” TS UNC and it’s been great for me. I would have gone with the 10/12” TS ONTC if I had not been able to bag the 12.5” Planewave. I don’t know the other options you’re considering but I can speak highly of the TS products that I have. 
Good luck!

Gary

[Spaceman 56]

an EQ8 is similar in size to my CEM-120 iOptron. I notice that you have an 800mm scope (F4 Newtonian) and are considering a larger version.

 

why not move up to a 10 inch RC ?  (second hand it meets your budget) 

 

1. you will get more focal length than a equivalent newtonian. my RC is 1484mm reduced at F5.9 and 2000mm native.

 

2. RCs have a fixed primary mirror, and thats helpful. mine has held collimation for 9 months despite being moved nightly.

 

3. RCs have a flat field native and don't need a COMA corrector.

 

I feel that RC images generally look better than SCT images. some people dispute this, but thats what my eyes tell me.

 

my 10 inch Truss RC runs good on my CEM-120, and the images look good too. just suggesting options here. 

Edited by Spaceman 56, 24 April 2025 - 05:33 PM.

[steveincolo]

The Starizona LF reducer is, I think, a better solution than an Edge HD with the Edge reducer.  The Edge reducers are just not amazing.  At full focal length the Edge spots are quite decent, but with a reducer they degrade to the point where I think you're better off with the non-edge scope and the Starizona LF reducer.

 

https://starizona.co...-coma-corrector

 

It's only for the 11" and 14" scopes.  A used model would probably be in your budget, at least for the 11".  I think the non-edge 11" model doesn't have mirror locks, whereas the non-edge 14" model I think does.

In theory, the non-LF Starizona reducer has a large enough (27mm) image circle for the QHY294M, doesn’t it?  I’m very happy with mine on my C8, but I only run it with 533 sized sensors.  

[jml79]

The regular Starizona SCT V4 will support an APS-C with acceptable vignette according to 2 youtube reviews I could find. The 294 is a 4/3, so it should have no issue. But nice big pixels and huge Ha sensitivity compared to my IMX571.

[jml79]

The Starizona LF reducer is, I think, a better solution than an Edge HD with the Edge reducer. The Edge reducers are just not amazing. At full focal length the Edge spots are quite decent, but with a reducer they degrade to the point where I think you're better off with the non-edge scope and the Starizona LF reducer.

https://starizona.co...-coma-corrector

It's only for the 11" and 14" scopes. A used model would probably be in your budget, at least for the 11". I think the non-edge 11" model doesn't have mirror locks, whereas the non-edge 14" model I think does.

A used C11 might squeak into the budget but it's a big stretch. $3000Cdn translates to about $2100 USD. Another issue is supply. Finding a cheap, used C11 locally is a bit hard. Shipping in Canada is stupid expensive so nothing from out west and cross border is a bit of a mess right now.

[jml79]

an EQ8 is similar in size to my CEM-120 iOptron. I notice that you have an 800mm scope (F4 Newtonian) and are considering a larger version.

why not move up to a 10 inch RC ? (second hand it meets your budget)

1. you will get more focal length than a equivalent newtonian. my RC is 1484mm reduced at F5.9 and 2000mm native.

2. RCs have a fixed primary mirror, and thats helpful. mine has held collimation for 9 months despite being moved nightly.

3. RCs have a flat field native and don't need a COMA corrector.

I feel that RC images generally look better than SCT images. some people dispute this, but thats what my eyes tell me.

my 10 inch Truss RC runs good on my CEM-120, and the images look good too. just suggesting options here.

I did look into a 10" truss RC but they blow way past the budget at $4300 plus tax. Not a single one available on the used market. The 8" is cheap but none of them have the better rear cell that isolates the mirror from the camera. I would be willing to take a risk on the 10" truss RC but I want to avoid frustration that the 6" and 8" cause.

[jml79]

Just to be clear, I have 4 mounts, 3 mono cameras with wheels and filters and an OSC 585. The 3" scope is a little speed demon at f/4.5 and is perfect for my little CEM26. Them CEM might carry a 6" hyperstar but I am not confident of it handling an 8". My Newt will live on my EQ6R and the new scope on the EQ8. The 4" doublet and IMX585 will go on the less than stellar EQM35 to be used for EAA and visual with my kids. My 3" scope is a little work horse. It is just fire and forget. No fiddling, it just works.

Edited by jml79, 24 April 2025 - 08:36 PM.

[Spaceman 56]

I did look into a 10" truss RC but they blow way past the budget at $4300 plus tax. Not a single one available on the used market. The 8" is cheap but none of them have the better rear cell that isolates the mirror from the camera. I would be willing to take a risk on the 10" truss RC but I want to avoid frustration that the 6" and 8" cause.

you could consider an 8 inch RC and add the Nate Man Doo RC adapter plate, that decouples the primary from the focuser.

 

there is a considerable thread about this in the advances section. 

 

I think it makes the 8 inch RC a viable option.  

[jml79]

you could consider an 8 inch RC and add the Nate Man Doo RC adapter plate, that decouples the primary from the focuser.

 

there is a considerable thread about this in the advances section. 

 

I think it makes the 8 inch RC a viable option.  

That thing looks great. Unfortunately commerce between Canada and the USA has become a bit of an issue. I know someone that tried to ship a used telescope to Texas and the process to clear customs became untenable. They wanted either a social security number (we don't have those) or an IRS business registration number as well as the social security number for the recipient and a certificate of place of manufacture. Of course private citizens of a country other than the USA don't have US Social Security numbers and why would you register a business in your home county just so you can register it with the IRS so you can sell the occasional used item and who has a certificate of manufacture for anything you might buy as an end consumer. I understand that this is to prevent tariff leakage through a third party country and that is fine but the second order consequence is small transactions and customer service transactions like warranty and return have become near impossible. So until things hopefully get sorted out, I am unable/unwilling to buy from US based retailers and small businesses.

 

Please note, I am not passing judgement here or trying to be political in any way. Just observing the reality of a situation and adapting.

[bigbangbaby]

I’d go for the maximum aperture that your budget allows. A 12 in. f/4 Newtonian fits that niche. I wouldn’t rule out preowned. All of my scopes, except the 12.5” f/5 Newton that I built, are preowned. I think there is inherently less risk purchasing a used Newtonian than other scope types. They are mechanically and optically simple, and easy to upgrade. Best of luck.

[jml79]

Well, it was one heck of an adventure yesterday. I hunted all the sources for used scopes and found a ton of overpriced C8's with their craptastic Alt/Az mounts a few C9.25's and some C11's. No 12" imaging newts, no RC's at all. I checked Ottawa, Toronto and Montreal. One of the 9.25's came with a Starizon SCT V4, Baader twist lock and a few other essential for a very good price. I contacted the seller and we arranged to meet about an hour and a half from his house. A 2 1/2 hour drive for me in a town called Cornwall. I packed up the whole family and we started out for an adventure day with plans to take the kids to a big park after the sale. The drive was fine with minimal traffic and the seller was cordial and genuine. It turns out that although we had never met, we worked in the same industry and I knew some of his co-workers. He had bought the scope off of a lady who bought it new and quickly found out that a C11 is not a suitable first scope. He had ordered the Starizona reducer and other necessities but while he was waiting for all of the parts a RASA 11 came up for sale and he couldn't resist. Now he needed to sell the C9.25 to recoup his funds. The scope was almost new and looked it except for one small detail upon inspection. The corrector plate had broken somewhere in transit or storage. The look on the sellers face told the whole story. There was no shady dealings, both of us felt our stomach's sink. He offered to sell me all of the accessories including a ZWO EAF and bracket for a very reasonable price to try and recoup what he could and we both went on our way very disappointed.

 

While the kinds were burning off their energy at the park my wonderful wife came up to me to ask if there was any reason a C11 wouldn't work with all of my gear. I told her there was no real reason, it would be a bit oversampled but not to much. She showed me 3 C11's for sale in Ottawa (about another 1 1/2hr drive from where we were but no further from home) and commented how there seemed to be very few well priced C9.25's but people couldn't seem to sell the C11's and they all ended up selling pretty cheap. I explained to her the large size and mount difference between the C9.25 and the C11. The C9.25 can comfortably ride on a mid sized 45lb mount but the C11 really needs a mount in the 60lb plus class to do well and that was a pretty big barrier to entry. I happen to have an EQ8 so no issue there. I contacted the seller of the nicest scope and arranged to drive the circular route home to take a look. I inspected the scope and asked the story. Turns out he had had a C6 years ago and enjoyed it for imaging, left the hobby for a while and then came back and bought an AM3 and 60mm refractor. He bought the C11 as an upgrade for galaxy imaging and then found out the hard way that an AM3 was not the mount for a C11. It seems like a re-occuring story with these scopes. I haggled a little and drove away with a C11, dew shield and dew heater.

 

I pulled out my EQ8 this afternoon, mounted the scope, put on the diagonal and took a look at some very distant trees. Everything checked out. Then I mounted all of the equipment needed for imaging, reducer, EAF, camera, filter wheel etc and I had everything I needed. I have a feeling I will want to eventually get an OAG-L and ASI174 but I will run it either with my small OAG and Ceres-M (ASI120) for now or a 50mm guide scope. But I'm $500 under budget (if I don't count gas and food for the outing) so I should be able to get those soon. Now to build the new Observatory with enough room for all 3 rigs to run at once. Then I can tackle the SCT learning cliff and hopefully be ready for next galaxy season.

 

In the end, I got everything for just a little less than the price of a new C9.25. Someone was watching out for me yesterday. I just don't know why.

Edited by jml79, 27 April 2025 - 09:33 PM.

[KGoodwin]

I'm amazed that you can find so many used scopes readily available relatively locally.  I don't think that would be the case for me here.

[jml79]

I'm amazed that you can find so many used scopes readily available relatively locally.  I don't think that would be the case for me here.

I guess that depends on "relatively". Within 4 hrs of my house is easily 10 million people or about 25% of the total population of Canada. I live about a 1hr 20min from the east edge of Canada's largest city but it is so big that I live 2.5-3hrs from it's west edge. I am about 2.5 hours from the capital, another city over 1 mil and about 4 hours from Canada's second largest city, Montreal. Inside this giant triangle there is only 1 other city over 100,000. So it's always a short drive to decent skies. I live 15 minutes north of one of the minor cities in the region and have B3/4 skies. B2 is only about 30-45 minutes away and there is even B1 skies a couple of hours north of me. But Canada is very East/West laid out. Except for southern Ontario, you are never more than an hour or 2 from B2 anywhere in the country.

[happylimpet]

Then I mounted all of the equipment needed for imaging, reducer, EAF, camera, filter wheel etc and I had everything I needed. I have a feeling I will want to eventually get an OAG-L and ASI174 but I will run it either with my small OAG and Ceres-M (ASI120) for now or a 50mm guide scope. 

Great story! the 120mm is a horribly insensitive noisy old camera for an OAG - I had a terrible time using one. Lots of modern cameras are much better (perhaps the asi220mm/qhy5iii200m) - you dont have to go all the way to a pricey 174.