Help me decide what scope to buy

Robert Žibreg:
What focal length are you aiming for? Right now you are at 840/646, is that fine for you or would you like to go for more/less?

I like the focal length. I think around 800 to 1000mm focal length is very versatile. I could maybe gain more resolution until around 1200mm but any more than that? Doubt it

I would go for something with a longer FL so you've got more tools to chase those smaller objects.

I've been quite pleased with my Orion Optics Ideal 8 newt at 900mm. Holds collimation very well even though I take it in and out every night, and the aluminum tube is lightweight at 15 lbs (lighter than steel tubes at 21lbs or so) and cools quickly. I got some custom carbon fiber rings and Losmandy dovetail from Rouz Astro as well which have been great. Given this is close to your current FL, I have to imagine the OOUK Ideal 10 at 1200mm would perform similarly well (it's also only 25lbs instead of 37 lbs!) or the Ideal 12 or 14 (at 1200mm/30lbs and 1600mm/44lbs, respectively) could be a nice choice for smaller targets. They also have their AG top of the line astrographs that I'd assume perform quite well, though I have no experience with them.

If you did a dual setup, would it be on one mount or two separate mounts? I've seen lots of folks do dual 6" newts, (especially the Sharpstar carbon newts or the Apertura CarbonStar come to mind) but you've already got a scope around that FL, so you might as well get a second Esprit. 

I'm jealous. I'd love a dual setup someday… But today is not that day 😂 Good luck with your decision!

David Foust:
I would go for something with a longer FL so you've got more tools to chase those smaller objects.

I've been quite pleased with my Orion Optics Ideal 8 newt at 900mm. Holds collimation very well even though I take it in and out every night, and the aluminum tube is lightweight at 15 lbs (lighter than steel tubes at 21lbs or so) and cools quickly. I got some custom carbon fiber rings and Losmandy dovetail from Rouz Astro as well which have been great. Given this is close to your current FL, I have to imagine the OOUK Ideal 10 at 1200mm would perform similarly well (it's also only 25lbs instead of 37 lbs!) or the Ideal 12 or 14 (at 1200mm/30lbs and 1600mm/44lbs, respectively) could be a nice choice for smaller targets. They also have their AG top of the line astrographs that I'd assume perform quite well, though I have no experience with them.

If you did a dual setup, would it be on one mount or two separate mounts? I've seen lots of folks do dual 6" newts, (especially the Sharpstar carbon newts or the Apertura CarbonStar come to mind) but you've already got a scope around that FL, so you might as well get a second Esprit. 

I'm jealous. I'd love a dual setup someday... But today is not that day 😂 Good luck with your decision!

I will buy a second mount ;)
ahh, it is just so hard to decide. A 10 or 12 inch newton with a focal length a bit longer would be nice. Maybe i just need 3 setups

Anderl:
Hello fellow astro friends,

there was recently a thread that showed that most of the people here on astrobin own way more than only one scope
i am planing to get a second one for quite some time now but i just can’t decide what instrument would best fit me and my situation. 

rn i am using an esprit 120 at native focal length and with the 0.77 reducer together with an imx571 camera. 

There are really quite a few setups i already thought about. 

1. a second esprit 120. this would double my exposure time and allow me to get deeper pictures with and without the 0.77 reducer

2. either an 10 or 12 inch ontc/lacerta newton for small stuff and my esprit with the 0.77 reducer and a full frame chip to be able to get a big field. 

3. selling the esprit and get 2 8 inch newtonians to get signal fast. 

4. selling the esprit and getting an toa 130 for small stuff and an epsilon 130 for wide field imaging.


My budget is around 15k, i want 2 setups, my sky is around bortle 3 and my seeing is average Bavarian seeing, i am imaging in my backyard without an observatory and as i like being under the stars things should stay that way. 

I know there is no right answer to this but i am interested in what you guys would do. 

cs
andi

With a budget of 15,000, I'd say personally, EdgeHD 11 with hyperstar and an F/7 reducer, and forego the double setup.

It'll do everything you want to do without having to maintain two seperate systems (Plus F/2 in bortle 3 is madness).

Honestly your EQ6R could probably handle the 11, but if you're worried about that, get a CQ350. For guiding, I'd get an 740, 800 or even 850 IR pass filter and a camera sensitive to IR inside an OAG, It'll defeat the seeing, and allow you to guide very well on the big scope.

Plus it means you can take advantage of the EdgeHD sale that's on right now.

It is a big scope, but to be honest they aren't THAT heavy.

Anderl:
My budget is around 15k

Go big, TOA 150,  your telescope of a lifetime. Keep Esprit 120.

At that price point, assuming going for a refractor, I'd rather just get an Askar 203, and a 6200mm setup for it. Takahashi prices reflect quality really well, but I don't see any point in buying a substantially smaller refractor for nearly double the price for performance that is nearly completely negligible in practice.

Honestly after giving it some thought, with this kind of budget, you could in theory get a CQ350, C14HD, and all the fixins and enjoy a huge range of capabilities, albeit it is going to be substantially heavier. 

That's why I suggested C11HD instead initially.

The EdgeHD makes very little use for photography, people use STC's with reducer-corrector anyway.

The 8" Askar is a substantial scope. If any mobility is involved, that and the corresponding mount is definitely going to be a struggleware. On a permanent pier, by all means!

At that price point, assuming going for a refractor, I'd rather just get an Askar 203, and a 6200mm setup for it. Takahashi prices reflect quality really well, but I don't see any point in buying a substantially smaller refractor for nearly double the price for performance that is nearly completely negligible in practice.

Honestly after giving it some thought, with this kind of budget, you could in theory get a CQ350, C14HD, and all the fixins and enjoy a huge range of capabilities, albeit it is going to be substantially heavier. 

That's why I suggested C11HD instead initially.

The EdgeHD makes very little use for photography, people use STC's with reducer-corrector anyway.

The 8" Askar is a substantial scope. If any mobility is involved, that and the corresponding mount is definitely going to be a struggleware. On a permanent pier, by all means!

I respectfully have to disagree with the first half.

EdgeHD is the most popular photographic system on Astrobin by photo and user volume (over 28,000 images total on Astrobin, and over 1900 users- not including the normal XLT and RASA systems).

With the ability to image at or above F/10 (11 on the 14), F/7,  F1.9-2.2 (depending on the type), and soon F/4, EdgeHD is a very good choice for imaging. That's why I use one.

Normal SCT's with the reducer-corrector, while decent for astrophotography use, cannot match the quality of field produced by the EdgeHD consistently.

Now, granted it doesn't come without it's problems, my biggest complaint being that the EdgeHD 8 can't fully illuminate my Full Frame sensor, forcing me into a different design, or a larger EdgeHD. (Not that I could afford either, thank you college.)



Now, I do agree that the 8" Askar can be a pain in the glass if mobility is concerned, but shooting from a backyard is a little less demanding then say, loading up your truck and driving to a dark site, so theres a bit more setup time, and leisure can be taken to make sure you don't obliterate your knees or back when powerlifting the big hunk'o'glass.

The CQ350 I recommend for that payload weight class is a big, bulky mount too, so it's a good thing you pointed that out. I think we need more mounts in that payload class, because theres really only a few to consider, and they all have massive pros, and some pretty gnarly cons too (Get your game on Celestron, make a strain-wave mount already!).

FYI: standard sct-s with the Starizona 0.63x CONSISTENTLY beat the EdgeHD with the Celestron 0.7x.

I'd never let that 120 go if I were you , and I'd only consider a dual setup once you have a more versatile array of scopes. I'd get something long, the SCA260 mm by sharpstar comes to mind at 1300mm and f5.

FYI: standard sct-s with the Starizona 0.63x CONSISTENTLY beat the EdgeHD with the Celestron 0.7x.

I'd need to see spot data, but I do believe it, the 0.7x on the EdgeHD was designed decades ago, and hasnt seen much of an update. Thats why I don't use mine.

It's also a stacked system eventually: the "Edge" optics is simply a corrector group installed inside the baffle tube. Adding a separate reducer behind is not ideal. Just browsing trough astrobin data, the Starizona results seem to be significantly sharper to me, than the Meade or Celestron reducers. Also, if the reducer optics is a good design, you can benefit  from some "MTF compression" effect, meaning that you can almost maintain the same angular resolution as with the long original FL. In daylight photography I got the same from my Metabones 0.64x (this actually might be an option for an EdgeHD + zwo astrocam combo)

No proper official spot diagram for the 0.63x unfortunately, this is the best I got:
https://www.widescreen-centre.co.uk/user/products/large/starizona_sct_corrector_web_01.jpg

Impressive, maybe my next scope should be an XLT with that Starizona reducer instead, my only concern is I don't know if it'll illuminate an IMX410. The LF reducer probably would. Other concern is the lack of mirror locks, on my next scope I don't want to deal with mirror shift at all. Maybe I should keep thinking about a 12" RCT.

Anderl:
how will the sharpness and the vignetting of an 9.25 or 11 sct paired with the reducer be if compared to a quality newtonian f4/f5 with an 2 inch focuser?

I am not sure "sharpness" and edgeHD/xlt are often used in the same sentence ;-) 

If you want sharpness, get a newt (and stop fretting about collimation - it's a non-issue if you buy a decent scope  and not hard once you have done it once or twice).

The edgeHD is more about having an incredibly versatile scope that can go both long and fast, but with compromises to both scenarios. You can use it for both planetary and widefield - there aren't too many scopes that can do this.

It's also big and heavy - which in itself may affect things like which mount you have to use, how often you setup/use etc. 

Again I will mention the Epsilon (I am biased because it's what I use and I love it): light, fast and (relatively) inexpensive. Collimation holds for months/years. The focuser sucks and has to be replaced, but other than that its great.

...and its yellow.