Autoguiding - in which way

[jm_rim]

I'm going to upgrade my EQ5 mount, either with the dual axis engine kit or the SynScan GOTO Kit, to be able to auto-guide. My primary imaging scope is the Skywatcher Explorer-150PDS using a Nikon. My goal at this time is to get subs of 300sec (of course higher if possible), as cheap as possible, as i’m still learn :-) At some point I want to upgrade the mount, scope, and ccd but need a lot of more money and experience first.
I have read a lot about autoguiding and can see that there can be some difficulties. From what I've been able to read, the biggest problem with auto-guiding a reflector is flexsure, and the best way to avoid this is at OAG. However, that this can be difficult (eg. requires more sensitive guide camera - increasing the prices a lot).

So my question is, with a goal of subs of 300 sec - and preferably keeping it under 350£ - should I go for:

1. OAG and QHY5-II-M guide camera - and is it sensitive enough?
2. Guide Scope Bundle - Suitable for Piggy Backing (https://www.firstlightoptics.com/guide-cameras/guide-scope-bundle-suitable-for-piggy-backing.html) - or would I risk too many issues with flex sour?
3. Finder-Guider Scope (like https://www.teleskop-express.de/shop/product_info.php/info/p7073_TS-Optics-Deluxe-60-mm-Guiding-Finder-scope-with-microfocusing. html) and a sensibly priced guide camera - like ToupTek or Zwo

Jesper
 

[freiform]

Hi Jesper,

I use a ZWO ASI120mm with a 9x50 standard (skywatcher?) finderscope. This setup is sufficiently sensitive and works quite well. The finderscope you posted sure is the deluxe edition, although you probably will not use the microfocuser in conjunction with a cam? Unless you use a 1.25" nosepiece, of course. I would probably go for a more permanent connection with the T2 thread.

 

Sven

 

/edit

I can also recommend the SynScan upgrade kit. Very handy and so many possibilities and comfort. I have one for my Vixen GP.

[Gerry Casa Christiana]

Yes you can get the ZWO 120mm (make sure it's mono) and the miniguidescope 

http://www.modernastronomy.com/shop/accessories/qhy-accessories/qhy-miniguidescope-kit/

fits right where the finderscope goes on the Skywatcher 150pds it's also my scope and guide setup. 

Easy!

 

[spillage]

+1 @freiform This would be the lightest and cheapest option. Check out the second hand market first. You should end up with enough left for a coma corrector or even a second hand 130pds which would help with weight on the eq5 giving you a better fighting chance.

[John78]

3 hours ago, jm_rim said:

I'm going to upgrade my EQ5 mount, either with the dual axis engine kit or the SynScan GOTO Kit, to be able to auto-guide. My primary imaging scope is the Skywatcher Explorer-150PDS using a Nikon. My goal at this time is to get subs of 300sec (of course higher if possible), as cheap as possible, as i’m still learn :-) At some point I want to upgrade the mount, scope, and ccd but need a lot of more money and experience first.
I have read a lot about autoguiding and can see that there can be some difficulties. From what I've been able to read, the biggest problem with auto-guiding a reflector is flexsure, and the best way to avoid this is at OAG. However, that this can be difficult (eg. requires more sensitive guide camera - increasing the prices a lot).

So my question is, with a goal of subs of 300 sec - and preferably keeping it under 350£ - should I go for:

1. OAG and QHY5-II-M guide camera - and is it sensitive enough?
2. Guide Scope Bundle - Suitable for Piggy Backing (https://www.firstlightoptics.com/guide-cameras/guide-scope-bundle-suitable-for-piggy-backing.html) - or would I risk too many issues with flex sour?
3. Finder-Guider Scope (like https://www.teleskop-express.de/shop/product_info.php/info/p7073_TS-Optics-Deluxe-60-mm-Guiding-Finder-scope-with-microfocusing. html) and a sensibly priced guide camera - like ToupTek or Zwo

Jesper
 

So first - check out https://www.astroeq.co.uk/tutorials.php depending on your bodgery skill level you can buy one ready to go and make some brackets or you can build one from a mega2650 - that should get you dual axis belt driven mount with eqmod for £150 absolute worst case, then an ASI120MM or QHY5-II or clone and a 9x50 finder, another £150.  Although your 150PDS probably came with a 9x50 so you can save £40 there, you don't need a finder scope when you can plate solve.

The Synscan upgrade for an EQ5 is like £309, then you still need to get guiding.

 

edit : to agree with @spillage with the money you're going to save I'd be buying a 130PDS, its well within an EQ5's limits.

[wimvb]

I have the 150PDS with ST80 guider bundle from flo. But I swapped the toucam for an ASI120. Weight should be your first concern. Also with a piggy backed guidescope, you move the center of gravity further away from the mount. For a stable mount (such as my az eq6) that is not at its limit, that's not a problem, but if you get close to the maximum load, it may be.

A finder guider is lighter, but somewhat less sensitive because of smaller aperture. If you plan to upgrade, consider a finder guider with a small camera, like the new asi or the qhy 5. You can later reuse the camera with an oag, or with a larger guidescope on a more stable mount. With a finder guider on an eq5, 5 min subs should be possible, even if you have to discard some. And it will be a good learning opportunity. Smaller investment now and upgradable, is the way I would go.

With a finder guider and some diy, you can also use the guider with your camera and an ordinary lens. Something you won't be able to do with an oag.

[jm_rim]

Thanks for the feedback,

It’s good to know that it is possible with a finder guider especially to save weight, which is my biggest concern - considering my current setup ... I'm not sure if I got it clarified good enough, but I’m thinking of Spending max £ 700 in total, for both mount upgrade and auto guidance.

Do you think I'm too close to weight limitation with my current scope?

[wimvb]

The 150PDS is sold as a kit with the smaller eq3 mount. The eq5 should be ok, if you don't add too much gear, balance it properly, and keep the mount in good shape. The most common problem with cheaper mounts is backlash, which is quite straight forward to reduce.

If you can afford it, you should consider the goto upgrade. With goto it's easier to get targets in the fov, and you have the possibility to use computer control (ascom or indi).

[spillage]

You could get a heq5 second hand for 4-5 hundred pounds, guide cam for 100ish maybe a st80 for 60 second hand, so lowest cost would be about 560 and enough left for a second hand 130pds. But I guess you need to really think were to spend the money.

I would prefer to spend it on the mount and build it from the ground up. You will always need to buy that bit of kit to sort out issues or make things better so I do not think you could spend your budget and say "that's it all done, no more kit to buy". I do not know you age but buy well even if you have to save for a while to get there.

[Stu Wilson]

Ive over the last year upgraded to neq6pro mount for my sw200p it carries my canon 650d dslr and just got orion starshoot guidescope finder outfit. So far working well. :-)

[jm_rim]

One thing is decided, upgrade to GOTO, but I'm not entirely sure about auto guiding yet.
I've found QHY5-II on sale (http://www.365astronomy.com/QHY-5-II-MONOCHROME-Planetary-and-Guide-CMOS-Camera.html) and combining it with a Guidescope (http: // www. 365astronomy.com/365Astronomy-60mm-Compact-Delux-Finder-and-Guidescope-Kit-with-1.25-Non-Rotating-Helical-Focuser.html) will be the cheapest solution, but will a piggy back solution with Startravel 80 bolted to a dovetail be a better solution??

[wimvb]

Even if you go with a finder guider, bolt it to the main scope. Don't rely on the finder holder, it isn't intended to hold a guider. The st80 has larger aperture (= more faint stars in fov), but also smaller fov. The st80 is heavier, so more stress on the mount. The longer focal length matches the scope's focal length better, so guiding accuracy on the imaging camera is closer to that of the guide camera. All these are pros and cons.

Personally, I would make my first concern to stay within the load capacity of the mount, and probably go with a finder guider for a smaller mount. If that proves not up to the job, I would take it from there.

 

[carastro]

I use a finderguider with my set up and even though I have the mini guide rings for mounting it, I find the finderscope bracket works just fine, so since this enables quicker and easier set up, especially with my dual mount, I just use the finderscope bracket.   I have an assortment of scopes, and in the past owned a SW 150P and the guider worked fine with that, I even used it on the larger 200PDS at one time.

HTH

Carole

[Stu Wilson]

The Neq6pro once you've polar aligned and done a 3 star alignment works very well on its own. However longer subs do require that little extra push over the cliff. Guiding is a must.

[jm_rim]

12 hours ago, carastro said:

I use a finderguider with my set up and even though I have the mini guide rings for mounting it, I find the finderscope bracket works just fine, so since this enables quicker and easier set up, especially with my dual mount, I just use the finderscope bracket.   I have an assortment of scopes, and in the past owned a SW 150P and the guider worked fine with that, I even used it on the larger 200PDS at one time.

HTH

Carole

That's nice to know :-) which finderguider do you use? 

[jm_rim]

11 hours ago, Stu Wilson said:

The Neq6pro once you've polar aligned and done a 3 star alignment works very well on its own. However longer subs do require that little extra push over the cliff. Guiding is a must.

If I had the money I would love a EQ6. With my current setup, EQ5 and a RA moter, and good polar alignment I have been able to get 120-150 sec subs. But sadly not enough keepers..

[jm_rim]

13 hours ago, wimvb said:

Personally, I would make my first concern to stay within the load capacity of the mount, and probably go with a finder guider for a smaller mount.

I will try to find a light weight solution. The load capacity is my main concern, and I hope to upgrade the mount as soon as I can afford it. But that just adds a lot of new questions, eg EQ6 or wait and buy one of the big ones, but that is for another time ;-)

[Guest Tuomo]

I have belt driven AstroEQ modded Eq5. I use 130pds with canon 500d. I guide with finder guider. I can easily make over 5min subs. 

[jm_rim]

56 minutes ago, Tuomo said:

I have belt driven AstroEQ modded Eq5. I use 130pds with canon 500d. I guide with finder guider. I can easily make over 5min subs. 

That sounds very interesting. How is it set up? 

• Belt drive to AstroEQ
• AstroEQ to computer 

but what about the guide camera? Is it connected to AstroEQ or computer and do you control it all through Stellarium or similar?

[Guest Tuomo]

14 minutes ago, jm_rim said:

That sounds very interesting. How is it set up? 

• Belt drive to AstroEQ
• AstroEQ to computer 

but what about the guide camera? Is it connected to AstroEQ or computer and do you control it all through Stellarium or similar?

 

AstroEQ is small box sided with my laptop. Those 2 are connected with usb. There are nema17 stepper motors in eq5. Motors are connected to AstroEQ box as well. Laptop gives commands to AstroEQ, which routes commands to stepper motors. 

[carastro]

Quote

That's nice to know :-) which finderguider do you use? 

I use the Skywatcher 9 x 50 finder that comes with the ED80 and ED120.  I also have a SW130PDS but I can't remember what finder came with that.  Hopefully you have the 9 x 50 with the 150PDS which will do just fine. 

Carole   

[TareqPhoto]

I asked about guiding too but couldn't find a clear answer myself, so i went with things slowly and i am still going.

First, i bought a finder scope, which is ZWO 60mm, then i ordered QHY5L-II-M, luckily i found it cheap price but with free shipping, so the only thing is left or lack is to buy an OAG just in case, not sure which but maybe one day i get something proper to use, and i am not in rush, i tried to take 300sec subs before without guiding and it wasn't good but close to be good, not sure if it was due to polar alignment, but being close to be good means if i can go guiding and check out PA accuracy then i can go even longer than 300sec, but very recently some told me to stay with something like 30-60 seconds only, if longer than 2 minutes maximum, if that is so then i don't need a big guiding tools, QHY5 is a nice camera really, and this ZWO 60mm finder is a reliable one even i didn't use it for guiding yet.

Take your time,, i keep reading everywhere and taking like 1-2 months or even more for one item or more, because i try to buy things once, even with not top or high end i try to have something that are quality-like equipment as possible, i skipped AVX and EQ5 and went with EQ6 from beginning, i can't go to Paramount or Astro-physics mounts due to price, also i can't buy Takahashi scope but it doesn't mean i will buy a $400-800 scope as will, i bought ST80 for practice and i can ne ready for a scope that is about $1500-2000, so i try to be in the middle for equipment if possible.