Decided on a Newt – but which one?

[Nigeyboy]

Hi all,

Another noobie question, so apologies if this has been asked many times before!!

I am slowly getting myself a little set up together. I already have the mount (EQ3-2), and am looking at various OTA’s to put on it. After lots of research and thinking about my long term plans, I have decided to get a Newt. So narrowed that bit down! I have now narrowed down the choice of tube. Please bear in mind this will be for visual only to start with.

SW 130p-ds

SW 150p-ds

SW 150p

My questions are:

Apart from the dual speed focuser on the pds versions, are the 150p and 150p-ds basically the same?

Can the 150p version be used for AP in the future (with a coma corrector of course, but the p-ds needs that too)

The 130p-ds is obviously 20mm smaller than the 150. As I’m planning visual for the time being I am guessing that the extra aperture on the 150 would benefit me more in the long term?

I want to get my choice right. Long term plans are to save for an HEQ5 / EQ6 in about a year or two. Is a 150 Newt OTA manageable for AP on these mounts?

Thanks in advance

Nige

[mikeobrien]

My friend has a sw200pds on an HEQ5pro and gets great images with it. Its a really nice setup.

[faulksy]

sorry to disappoint you but the eq3 will struggle with a 6" newtonian, best and cheapest method especially for visual is a dob, something like this

http://www.firstlightoptics.com/dobsonians/skywatcher-skyliner-150p-dobsonian.html

or the 200

[Nigeyboy]

sorry to disappoint you but the eq3 will struggle with a 6" newtonian, best and cheapest method especially for visual is a dob, something like this

http://www.firstlightoptics.com/dobsonians/skywatcher-skyliner-150p-dobsonian.html

or the 200

Really? I was under the impression that the 150 would be ok on the EQ3-2 for visual? I am planning on filling the legs with old .22 lead pellets to help damp it a bit . . . .

[xtreemchaos]

hi nige i havent got any of the ota your looking at but i do have a 200p witch is the 150p bigger brother,skywatcher are well made and easy to use, i think the difference between the 150p and 150pds is dual speed focuser and baffels and i think 150pds is a bit shorter "but im not sure some one will know on here" i find my 200p is my fav scope and its the one i would never let go" it would have to be rip from my cold dead hands ha ha" i wish you luck with your new scope,all the best charl.

[Andy Mitchell]

Older versions of the 130p/150p couldnt reach focus for photography as the camera sensor (at the back of the camera) needs to be closer to the scope than an eyepiece and there wasn't enough inwards focus range. So you needed the 130p-ds/150p-ds for photography, as they had the the primary mirror closer to the focuser to move the focal plane outwards. They come with an extension tube you pop in when using eyepiece.

I've heard the current non-ds versions no longer have this limitation but I can't swaer thats true! I would still want the ds version as precise focus is very important to get decent AP results and its hard enough with the dual speed focuser

130p-ds + HEQ5 (synscan/syntrek versions) is a very popular combo for astrophotography and people are doing stunning stuff. HEQ5 would handle the 150p-ds fine as well.

EQ3-2 is not a mount I've used but as its the mount they often bundle with this size scope it will probably be slightly wobbly and just about useable for visual.

[Piero]

I want to get my choice right. Long term plans are to save for an HEQ5 / EQ6 in about a year or two. Is a 150 Newt OTA manageable for AP on these mounts?

Hi! 

For visual only I would go for a Dob 200 F6. However, you mentioned that in the long term you would like to do some AP and put it on a HEQ5. I don't do imaging, but I believe a Newton 200 F5 on a HEQ5 is at the very limit. An EQ6 is better of course, but will be very heavy if you want to take it around. 

One way is to separate the two things (visual and AP). In this case, a Dob 200F6 now (an AZ mount is far easier to use) and later in the future if you really decide to do AP, an Equinox 80 mounted on a HEQ5 would be a sensible choice for starting as many users can report.

If you really want just one telescope for visual and AP, you could go for the newton 150, but I feel you need to upgrade your current mount as also suggested by other members. You could also consider an AZ4. In this case you would have an AZ4+N150F5 for visual and HEQ5+N150F5 for AP. The combo AZ4+N150F5 is very easy to mount and strong.

The main differences between P and PDS are the focuser and the secondary size. For AP, it might be worth the PDS version as it has a larger secondary mirror, but many folks don't complain with the P version much. You may want to read a bit more about these two variants. There are many threads about it. 

Also consider that you will need to add a new finder (possibly a RDF Rigel could be a good choice.. up to you) and as the N150 F5 is fast, you will need good eyepieces. Just a reminder.

Piero 

[Chris]

A Newt on an EQ for visual = bad back

[Nigeyboy]

Wow – lots of replies, with lots of good advice, so  thanks for all the feedback so far. There are so many pro’s and con’s for every step you take in this hobby!! I suppose it’s a matter of weighing them up. I haven’t the budget to get a new mount right now, so I will have to make do with the EQ3-2. I will pimp it as best I can to improve the stability.

 

Thought I had this sussed lol!!

 

 

[ronin]

SW 130p-ds

SW 150p-ds

SW 150p

My questions are:

Apart from the dual speed focuser on the pds versions, are the 150p and 150p-ds basically the same?

Can the 150p version be used for AP in the future (with a coma corrector of course, but the p-ds needs that too)

For imaging you really need the pds designated scopes.

They have the 2 speed focuser, and the scope can actually get an image on a DSLR. You can move the 150P mirror up the scope if you wanted to - this pushes the image plane out and so the image can get at the DSLR sensor. Just more problems.

So the 150P can be used by it is a bit more involved.

Mount, for imaging the EQ3-2 is really too unstable, so you are looking a at the EQ5 as a realistic minimum.

It is probably too light weight for visual as well, thisngs will shake a lot, especially when you touch it or look through it.

Unfortunately the supplied mount in a package tends to be the minimal that they can get away with.

Budget may not allow it but there is a serious case for a visual set up and an imaging set up.

[Piero]

A Newt on an EQ for visual = bad back

Also a Dob 200 without a chair ! 

[Chris]

If it's the newer black 150p it reaches focus with a dlsr just fine, I've taken some of my best pics with a 150p. The older blue tube 150p doesn't reach focus, but these are getting to be quite old scopes now.

[xtreemchaos]

can i just add i get good focus with my 200p EQ5 its the black one and the mount is very steddy with the s/steel legs.

[swamp thing]

After having used a 6" newt on an EQ3-2 visually. I would have to say it was a less than successful pairing. The mount wobbled like crazy every time one touched it.  A very frustrating experience to say the least.

Not a combo I would recommend. 

[laser_jock99]

The EQ3-2 will handle a 150PDS for visual and basic AP and they are frequently sold together .

I have the above combo- but must admit to never having used it yet (due to availability of other mounts). 

Of the three scopes you mention the 150's (preferably the DPS) would be best for visual, but the shorter focal length of the 130PDS might be more forgiving on that mount for AP.

[hgjevans]

A Newt on an EQ for visual = bad back

I'm always a bit perplexed when I see people say that, because that's not my experience at all. Quite the reverse, in fact, because no matter where in the sky I'm observing I can always turn the scope in the rings to place the eyepiece so as to be able to view in a (reasonably) comfortable standing position. It's actually one of the various issues that decided me against a Dobsonian of similar aperture - because I really couldn't see how I would be able to achieve the same with a dob mount. My back is fairly susceptible to aches and pains, but a Newt on an EQ works for me.

[Nigeyboy]

Maybe I should save my pennies for a Paramount ME lol!!!

I’ve seen a 150p OTA on ABS for £159 – the same cost as a new 130p-ds . . .

Given that many of you think the EQ3-2 is insufficient for a 150, how about the 130? Smaller profile so less of a sail, and lighter I assume? Or should I go back to my original plan of a small 80 or 100 frac?

[Chris]

I'm always a bit perplexed when I see people say that, because that's not my experience at all. Quite the reverse, in fact, because no matter where in the sky I'm observing I can always turn the scope in the rings to place the eyepiece so as to be able to view in a (reasonably) comfortable standing position. It's actually one of the various issues that decided me against a Dobsonian of similar aperture - because I really couldn't see how I would be able to achieve the same with a dob mount. My back is fairly susceptible to aches and pains, but a Newt on an EQ works for me.

Yes agreed, if you undo the rings and move the ota around and re-tighten the rings for every object then you can observe comfortably. Maybe it's just me not wanting to do that for every object? I don't think you have to do this for any other type of setup,?

I'll personally stick to my observing chair!  

[triton1]

The 130 would be ok on that mount but for visual only but then saying that people have managed to get cracking pictures with that setup.I have the 200p on a cg5 with 2 inch tripod and that still vibrates slightly when there,s a breeze about so I would stick to visual only and save up for the heq5 which seems to be the minimum requirement.Also buy the book "every photon counts" and read it several time.Going to the dark side can cost the same as a new car so reading this book may save you a fortune or not or keep you a visual astronomer who actually uses an eyepiece.

[Nigeyboy]

Thanks John. As I said in my opening post, this will be a purely visual set up. I am under no illusions that the EQ3 isn’t the best for AP, especially with a 150 atop it! My long term plan will be a new mount in 12-18 months, or however long it takes me to scrape the money together!!

That being said, my research on the t’interweb has shown that with some effort the EQ3 can be used for DSLR AP. That is something I will perhaps have a go with. I only have the one DSLR lens – a Canon 17-55mm f2.8, so with a RA motor on the mount I may get some passable results!!

[triton1]

Yes Chris I do agree in part with that.I use a couple of hoops clamped to the ota to keep balance when rotating the tube but then concentrate on a certain part of the sky most I,ve ever changed is twice but the joy of sitting down at the ep is so very tempting I can taste it and my legs are already telling me to buy an sct.

[triton1]

There is a thread on here somewhere on the lines of images taken with the 130.maybe worth trying to find it and check out their setups.

[Nigeyboy]

I found that link a while ago John – some stunning work being done by the peeps on SGL!! That’s what got me thinking about Newts in the first place lol!!

[triton1]

I too was blown away with what can be done with the 130 I guess it's because of the weight of the ota that's made it so popular.

[Alien 13]

The 130pds with the EQ3-2 will be ok for visual and some limited AP but you would be restricted to subs of around 45s but with the fast optics that would be enough to get a real taste.

If you go for the enhanced motor kit you can add guiding at a very reasonable price and even after a mount upgrade still have the EQ3-2 as a lightweight portable camera/lens setup for those dark sites.

Alan