Calling all medium/big newt imagers (the telescope, not the salamander)...

[The Lazy Astronomer]

...your advice is requested please! 

As a purely refactor guy for DSOs, I'm thinking about losing my mind (😁) and buying one of the relatively inexpensive (compared to an apo frac) 10" newts (e.g. SW250PDS) for an attempt at some galaxy imaging in the spring, and maybe, if that turns out to be a bust, turning it to planetary imaging use.

Any advice for me with this journey? 

What are they like to image with? Will I be pulling my hair out trying to get one of these cheaper scopes to perform? 

[Mandy D]

3 hours ago, The Lazy Astronomer said:

...your advice is requested please! 

As a purely refactor guy for DSOs, I'm thinking about losing my mind (😁) and buying one of the relatively inexpensive (compared to an apo frac) 10" newts (e.g. SW250PDS) for an attempt at some galaxy imaging in the spring, and maybe, if that turns out to be a bust, turning it to planetary imaging use.

Any advice for me with this journey? 

What are they like to image with? Will I be pulling my hair out trying to get one of these cheaper scopes to perform? 

I love my two Newts. I have a 200P and a 250PX and I find both easy enough to use. Obviously mine are not astrographs and would have the problems associated with that if you wanted to add a full imaging train to the focuser. With a Newt everything seems to come down to two things: quality of finish of primary mirror and collimation. The focuser can always be upgraded if that were an issue, of course. The central obstruction does cause a small loss of contrast as all the frac enthusiasts keep reminding us, but I find it is easily recovered in processing.

I don't think you will end up pulling your hair out trying to get a good image out of your proposed scope, but you might catch a dose of collimation fever! To be honest, I don't generally bother checking my collimation and still get acceptable results, so unless you are a total perfectionist, it should be good. I do like my RC6, though.

If the scope is not up to expectations, upgrade the focuser, get the primary mirror refigured to 1/10 wave or better if that is your desire, maybe replace the secondary with a better one and you really have not lost a lot. In all events, it will work well for planetary imaging when Barlowed. Personally, I prefer focal extenders, but whatever suits.

With the right mount, they work well.

[tooth_dr]

I currently have a 200p and a 250px and  for a brief stint had a 300pds.

I haven’t imaged with the 200 yet but my 250px is my ‘go to’ galaxy scope from March to May.

Easily collimated by eye, but the Ocal collimator tool makes it objectively accurate, and I would highly recommend it.

The focuser is good with light stuff, and just adequate with heavier stuff.

If you don’t have shelter from wind I wouldn’t recommend a large newt though.  The 250px fits comfortably in a 2.2m pulsar dome, the 300 would be very tight.  I used to use it in a roll off roof obsy and unless it’s dead calm you would lose subs.

[Ouroboros]

Let’s put it this way. I owned and imaged with a 200p for several years before owning my cheap SW refractor. I learnt about imaging using it, and had some reasonable results. However, since getting the refractor several years ago I have never really returned to my reflector for imaging.  I personally find imaging with a refractor a more enjoyable and rewarding process. Admittedly that’s for deep sky only.  I wouldn’t and don’t use it for planetary.  I like the fact I keep the telescope, main camera, guide scope +cam, ASIair permanently together as a unit. I just pick ‘em up whole and put them on the mount. Done. Ready.

 

[pipnina]

My small 130PDS did very nicely (with the exception of its known design flaws, primarily the focuser tube protrusion). But of course this is a fairly small scope compared to what you're thinking of, it still did nicely on small-ish galaxies:

 

I also used a scope more in the realm of your considerations: A TS-PHOTON 200/800. That made nice images... When behaving. It also seemed to suffer more from not producing a flat background, maybe the tube walls were not black enough or somesuch. It also NEVER kept collimation, it required modifications to be usable at all for imaging as the collimation shifted just by changing where the mount was pointing... I also never got it to dial in perfectly, all of my images with the scope have some coma or astigmatism somewhere.

The images I *did* get, I was mostly happy with. It wasn't easy to gather them though!

My advice: If buying a smaller newt, go cheap and do things like put flocking material on the inside of the tube and blacken the secondary edges. If buying a bigger newt (i.e. larger than 150mm) you need a more expensive model to have any ease of use. For some reason the step up from a 5/6" mirror to 8" increases the hassle involved massively unless the scope is better mechanically designed.

Good luck!

[Paul M]

This current thread might be of use too, we'll until it slips off into esoteric territory 🤪🤣

 

[tooth_dr]

Just now, Paul M said:

This current thread might be of use too, we'll until it slips off into esoteric territory 🤪🤣

 

And a great m51 there

[Paul M]

2 hours ago, tooth_dr said:

And a great m51 there

It's definitely ok. But just wait until I get my RC10 in full flow...😎

[The Lazy Astronomer]

3 hours ago, tooth_dr said:

If you don’t have shelter from wind I wouldn’t recommend a large newt though.

Hmm. Yes, this was one of my concerns. No shelter other than a fairly secluded garden.

2 hours ago, Paul M said:

This current thread might be of use too, we'll until it slips off into esoteric territory 🤪🤣

 

I did wonder if this might become another thread on sampling rates, but that one seems to have it covered. 😂

The RC8 was in my consideration as well, and it would probably be the better choice for me in terms of size, but I've read enough comments on collimation difficulties to make me apprehensive about it.

Plus, it's almost twice the cost of the newt.

3 hours ago, Ouroboros said:

I like the fact I keep the telescope, main camera, guide scope +cam, ASIair permanently together as a unit. I just pick ‘em up whole and put them on the mount. Done. Ready.

Yep, one of things l love about my frac is the speed set up and ease of use. Everything just works, no faff. 

Were there any particular frustrations you had with 200p?

3 hours ago, pipnina said:

My small 130PDS did very nicely (with the exception of its known design flaws, primarily the focuser tube protrusion). But of course this is a fairly small scope compared to what you're thinking of, it still did nicely on small-ish galaxies:

 

I also used a scope more in the realm of your considerations: A TS-PHOTON 200/800. That made nice images... When behaving. It also seemed to suffer more from not producing a flat background, maybe the tube walls were not black enough or somesuch. It also NEVER kept collimation, it required modifications to be usable at all for imaging as the collimation shifted just by changing where the mount was pointing... I also never got it to dial in perfectly, all of my images with the scope have some coma or astigmatism somewhere.

The images I *did* get, I was mostly happy with. It wasn't easy to gather them though!

My advice: If buying a smaller newt, go cheap and do things like put flocking material on the inside of the tube and blacken the secondary edges. If buying a bigger newt (i.e. larger than 150mm) you need a more expensive model to have any ease of use. For some reason the step up from a 5/6" mirror to 8" increases the hassle involved massively unless the scope is better mechanically designed.

Good luck!

Love the ghost nebula - one l really want to do soon!

You've basically described all the reservations I have about going down this route, but good to hear them from someone with first hand experience. 

The higher quality newt options would clearly give me a better ease of use experience, but then I think we're up in RC and Edge HD price territory which further muddies the waters with other potential options. I get the feeling I'll be stuck in analysis paralysis for sufficiently long that galaxy season will come and go - problem solved 😂

[Paul M]

27 minutes ago, The Lazy Astronomer said:

I get the feeling I'll be stuck in analysis paralysis for sufficiently long that galaxy season will come and go - problem solved 😂

Yup, that was me for the last 12 months!

One thing I take comfort in is that the more I think about choice the more certain I am to make the wrong one! So no disapointment down the line.

The 250PDS I bought 9 years ago now was for visual. I'd read about how high the eyepiece would be at the zenith but still had to find out for myself! Optically it's been great and in the right hands, as others have shown, is capable of great imagery. 

I just wanted more focal length and decided an SCT would be too much. So the RC won the day. But even if I collect great data with it, my processing will ruin it! 

[Ouroboros]

@The Lazy Astronomer You asked me “Were there any particular frustrations you had with 200p?”.  Yes, there were. Coma was very much a problem with eggy stars away from the central region.  I bought a coma corrector, which I used a few times, but found it produced peculiar  reflections.  As mentioned earlier, a large reflector acts as a huge sail even on a decent mount. Even a slight breeze would result in my having to throw away quite a few subs. Dew was sometimes a problem too despite using a dew shield and a dew strap.  Dew is easier to deal with on a refractor.

I still use my 200p for visual as it’s better for that than the frac. I still occasionally take pictures of the Moon using a DSLR attached to my 200p.

A friend of mine uses a large, long focal length Newtonian mainly for lunar and planetary photography in a very urban environment. He does very well with it.  I suggest that a large reflector offers certain advantages for lunar and planetary photography - not least because there aren’t the constraints of deep sky imaging.

As ever it comes down to what you want to do. 

[Jimbo64]

After deliberating and researching this topic for a while I've just bought a F/5 200PDS, the weather hasn't been great, so I've not used it much at all yet.  

Once I had decided to go down the large(ish) newt route the advice to me (specifically for imaging) was to conncentrate specifically on focal ratio, F4 being faster and 'better' for photography, but more challenging to manage (collimation and more in need of a coma corrector_ - something like: https://www.firstlightoptics.com/stellalyra-telescopes/stellalyra-10-f-4-m-lrn-newtonian-reflector-with-3-focuser.html.  I must admit that I bottled it a bit and opted for the F5 - it seemed to me a good compromise and easier to work with as well as being a good all-rounder for both imaging and visual use - and I settled on Skywatcher as it was bundled with the mount I needed also (HEQ5 pro).

If you can cope with the technicalities, a fast newt seems a good option, and the price (and sail effect) drops considerably if you drop aperture. 

[The Lazy Astronomer]

10 hours ago, Ouroboros said:

@The Lazy Astronomer You asked me “Were there any particular frustrations you had with 200p?”.  Yes, there were. Coma was very much a problem with eggy stars away from the central region.  I bought a coma corrector, which I used a few times, but found it produced peculiar  reflections.  As mentioned earlier, a large reflector acts as a huge sail even on a decent mount. Even a slight breeze would result in my having to throw away quite a few subs. Dew was sometimes a problem too despite using a dew shield and a dew strap.  Dew is easier to deal with on a refractor.

I still use my 200p for visual as it’s better for that than the frac. I still occasionally take pictures of the Moon using a DSLR attached to my 200p.

A friend of mine uses a large, long focal length Newtonian mainly for lunar and planetary photography in a very urban environment. He does very well with it.  I suggest that a large reflector offers certain advantages for lunar and planetary photography - not least because there aren’t the constraints of deep sky imaging.

As ever it comes down to what you want to do. 

The more I look for info, the more I'm seeing a lot of responses that basically say "don't do it!" I found another thread earlier asking a very similar question where literally every response said a big newt on an eq6 class mount with no wind protection would be a nightmare. 

I like to dabble in a bit of planetary imaging, but not enough to buy a scope solely for it, so I think I'm going to have to think a bit more and possibly save the pennies for a little while longer. 

[The Lazy Astronomer]

8 hours ago, Jimbo64 said:

After deliberating and researching this topic for a while I've just bought a F/5 200PDS, the weather hasn't been great, so I've not used it much at all yet.  

Once I had decided to go down the large(ish) newt route the advice to me (specifically for imaging) was to conncentrate specifically on focal ratio, F4 being faster and 'better' for photography, but more challenging to manage (collimation and more in need of a coma corrector_ - something like: https://www.firstlightoptics.com/stellalyra-telescopes/stellalyra-10-f-4-m-lrn-newtonian-reflector-with-3-focuser.html.  I must admit that I bottled it a bit and opted for the F5 - it seemed to me a good compromise and easier to work with as well as being a good all-rounder for both imaging and visual use - and I settled on Skywatcher as it was bundled with the mount I needed also (HEQ5 pro).

If you can cope with the technicalities, a fast newt seems a good option, and the price (and sail effect) drops considerably if you drop aperture. 

Yeah, I'm trying to avoid getting drawn in by the thought of a sub f5 newt, purely because I don't want the extra effort that comes with collimating fast optics!