Imaging with the 130pds

[JoshHopk]

11 minutes ago, alacant said:

Hi

Not sure what ISO you used but the 100d works best at 400. Maybe keep the exposures the same but at ISO400?

To see an improvement, keep taking frames until you just can't bear it any longer!

Cheers

Ah, I was shooting at 1600. Thanks for the info, I’ll use 400 next time. 

Thanks, Josh

[rotatux]

Only my 2nd attempt at Perseus Double Cluster with that tube.
I had this in stock since last year but didn't put online. Now the more time passes the more I like it, and no good night since, so here it is.

Gear: Olympus E-PL6 with Skywatcher 130PDS and SWCC at 600mm/4.62 and dydimium filter on Omegon EQ-300 tracking RA
Capture: 22 lights × 20s × 2000 ISO, master bias, at 1.28"/px
Site: deep country 26km from Limoges, France
Processing: Regim 3.4, Fotoxx 12.01+

[JohnSadlerAstro]

Hi everyone 🙂

My first attempt at processing with PixInsight, I have been quite relaxed with most of the processes there's probably still some room for improvement. 

M51, 4.5h of 120-180 sec subs @ ISO800. 

Eos 1000d, NEQ6 mount, autoguiding with asi120mm mini. 

I'm amazed by how many small galaxies are lurking in the background, there's a huge cluster underneath the bright star at the lower left. 

John 

Edited June 30, 2020 by JohnSadlerAstro

[Aramcheck]

8 minutes ago, JohnSadlerAstro said:

I'm amazed by how many small galaxies are lurking in the background, there's a huge cluster underneath the bright star at the lower left.

Nice pic!

Try having a go with the ImageSolver (Script->ImageAnalysis) + CopyCoordinates (Script->Utilities) + AnnotateImage (Script->Render)... Enable the PGC catalog -  you'll be amazed at how many faint fuzzies show up.

(If you want you can also then go to Simbad: http://simbad.u-strasbg.fr/simbad/sim-fid enter the PGC ref & often you'll find the radial velocity listed. Divide that by the Hubble Constant (68 - 70) to give the approx distance in MPc. Multiply the result by 3.26x10^6 to get the distance in light years)

Cheers
Ivor

[teoria_del_big_bang]

On 02/04/2020 at 16:41, mAnKiNd said:

For anyone interested in fixing their star shapes (subject is Vega) from this to this:

I designed a 3D print on tinkercad (.sti file attached)Skywatcher 130PDS Newtonian Primary Mirror Aperture Mask.stl, found a local 3D print shop to make it for me and applied to the mirror clips as such:

Inner diameter is 125mm, which is sufficient to cover the mirror edge and mirror clips. The idea is that the mask blocks the stray light from the edges, which causes the flares you see on bright stars and the ghost flares from the mirror clips blocking the edge flare.

Hope this helps

Minos 

Sorry to bother you @mAnKiNd but I want to print this.

The only question I have is that I have downloaded the STL file and checked the inside diameter and it is actually 121.5 mm not 125 mm as you mentioned. Can you just confirm is this correct at 121.5 mm ?

Steve

 

[g-rex]

Morning people. With this being all about the 130 PDS I thought this may be the best place to ask this question.

 

I'm using a 130pds on a belt modded exos 2 (eq5).

I'm thinking of starting to acquire the bits for guiding and wondered what length guide scope would suit best?

Am on a tight budget too so any links to cheap items would be greatly appreciated 😊.

[alacant]

12 minutes ago, g-rex said:

a tight budget too so any links

Hi

A works-for-me suggestion.

Fit a second dovetail plate along the top of the rings and bolt this to it: Guide telescope + guide camera

HTH

[g-rex]

Brillant. 

That's a 50mm guide so I know what size i need.

Thanks for the links, had seen the T7 recently and wondered about that. 

 

 

 

Thanks.

Edited July 2, 2020 by g-rex

[mAnKiNd]

On 30/06/2020 at 16:55, teoria_del_big_bang said:

Sorry to bother you @mAnKiNd but I want to print this.

The only question I have is that I have downloaded the STL file and checked the inside diameter and it is actually 121.5 mm not 125 mm as you mentioned. Can you just confirm is this correct at 121.5 mm ?

Steve

 

Hi Steve, sorry I just saw your message and also for any confusion. I just measured the spare one I had (I printed two at the same tine and don’t want to disassemble the installed one) with digital calipers and the inside diameter is 121.5mm - so I stand corrected, not sure where I got 125mm, maybe I made a typo and missed the number one and decimal, or maybe I’ve been abducted by aliens one too many times lol

In any case, at 121.5mm it completely mitigates flares, but feel free to experiment with larger inner diameters if you want to squeeze out as much aperture as possible 

Thanks for pointing that out and clear skies everyone. 
 
Minos

[Jamgood]

Finally joined the club. Excited to get started.

 

[Spaced Out]

On 25/05/2020 at 10:31, TheCounter said:

I'll post a detailed report as soon as it's getting clear again here.

Spacing isnt a big deal thought. Not like with the MPCC.

Just wondering if you're still happy with this CC v the Baader ? Do you have any comparisons ?

I'm considering maybe moving from MPCC to this CC if it performs better.  

Edited July 11, 2020 by Spaced Out

[TheCounter]

16 hours ago, Spaced Out said:

Just wondering if you're still happy with this CC v the Baader ? Do you have any comparisons ?

I'm considering maybe moving from MPCC to this CC if it performs better.  

Yes I'm really happy with the GPU, its way better than the MPCC. Let alone the fact, it's just too long to tilt, so no problem with that.

I'm not yet ready to post a in-depth review of it, as the weather is kinda "freaky" here in germany and it's not getting 100% dark thanks to summer. Should have it ready in a few weeks though.

But if you want a good CC, go straight for the GPU. I would never ever go back to the MPCC.

Btw. I'm really happy I bought a 3D printer. I always had to hook up my MiniPC (to control my whole setup, running on Windows 10) in a kind of strange way to my telescope. I now printed a case for it, that sits ontop of the telescope holding my guidescope

Old:



New:

Edited July 12, 2020 by TheCounter

[Spaced Out]

2 hours ago, TheCounter said:

Yes I'm really happy with the GPU, its way better than the MPCC. Let alone the fact, it's just too long to tilt, so no problem with that.
 

Thanks for this. In what way do you think it is better apart from the length/tilt thing ? Better looking stars ? Pinpoint stars ? Easier to space ?

Does it need a full length tube and do you have to wind it out quite a long way for focus ? I've got a heavy camera and FW on a stock SW focuser, I'm guessing the further it is wound out the less stable it might become.

[TheCounter]

2 hours ago, Spaced Out said:

Thanks for this. In what way do you think it is better apart from the length/tilt thing ? Better looking stars ? Pinpoint stars ? Easier to space ?

Does it need a full length tube and do you have to wind it out quite a long way for focus ? I've got a heavy camera and FW on a stock SW focuser, I'm guessing the further it is wound out the less stable it might become.

The stars in the corners look much better. With the MPCC, I always had a "softening" effect on them (coma and blur in direction of the corners), thats gone with the GPU.

Spacing is easy, I went with the recommendation of 53mm for my QHY294c.

And I need around 35mm backfocus, so you'll need to wind it out a bit more compared to the MPCC. But as it's so long, tilting shouldn't be a problem.

I did replace my focuser though, because the stock focuser was rubbish on my PDS. The new one is strong as hell, another league compaired to the SW focuser.

But to really be sure there won't be any tilt, I designed and printed a anti-tilt and rotation adapter. Thats 4 pieces, 2 hold onto the focuser itself, the other one pushes down the GPU and the third is for displaying camera rotation:

[Spaced Out]

23 minutes ago, TheCounter said:

The stars in the corners look much better. With the MPCC, I always had a "softening" effect on them (coma and blur in direction of the corners), thats gone with the GPU.

Spacing is easy, I went with the recommendation of 53mm for my QHY294c.

And I need around 35mm backfocus, so you'll need to wind it out a bit more compared to the MPCC. But as it's so long, tilting shouldn't be a problem.

I did replace my focuser though, because the stock focuser was rubbish on my PDS. The new one is strong as hell, another league compaired to the SW focuser.

But to really be sure there won't be any tilt, I designed and printed a anti-tilt and rotation adapter. Thats 4 pieces, 2 hold onto the focuser itself, the other one pushes down the GPU and the third is for displaying camera rotation:

That's impressive ! 👍

I wanted to replace my flaky SW focuser for a UNC V-power or Monorail focuser but I couldn't get an adaptor plate/base to fit it to the small OTA. All I could get off the shelf to fit was a Moonlite which was $$$$$. 

The stock SW focuser seems to be the weak point when you have a heavy mono camera, filter wheel and OAG attached.

[JoshHopk]

Hope I'm not interrupting anything! Really loving this little gem of a scope.

Imaging - SW130PDS, Canon EOS 100D. 28x 3mins @IOS800
Guiding - SW 9x50 Finder, ASI224MC
Mount - HEQ5 Pro (Rowan Mod)
Other - SW 0.9x CC
Stacked in DSS and processed in Photoshop 2020

Comments and criticism welcome!

Edited July 13, 2020 by JoshHopk
Pressed enter by accident!

[matt_baker]

This scope has served me very well but ever since I've acquired my 1600MM + filter wheel, it's been causing me a lot of trouble regarding tilt and bad stars. 

I tried to get around this by purchasing this item which claims to reduce the tilt, which it does, only very marginally compared to just three thumb screws. In the description of the item, it stated that it can be rotated with a counter ring. Although this does work, it doesn't hold it tightly enough and causes even more tilt than there already was, and again, probably something to do with the weight as I was very easily able to move the camera up and down.

I have three options to amend my situation.

1. I can try to think of something else to completely reduce the tilt enough for it to be acceptable. I was thinking of a baader clicklock but I've heard it doesn't work on the stock SW focuser

2. I buy a Moonlite CR2 focuser. Only issue I'm not sure about is the added weight of the focuser + the camera and filter wheel means that I won't be able to balance properly due to the focuser hitting the tube rings of the scope

3. I upgrade and buy something like an Esprit 80ED.

Saying this, I really do like the 130PDS. It's fast, has wide aperture and a decent focal length for a dirt cheap price. I also appreciate the challenges that comes with a newtonian and the rewards it reaps if everything goes right.

The item I tried: https://www.teleskop-express.de/shop/product_info.php/info/p5417_Lacerta-Thread-Adapter-for-using--Baader-MPCC-with-Skywatcher-Newtonians.html

[Stub Mandrel]

Have

19 minutes ago, matt_baker said:

This scope has served me very well but ever since I've acquired my 1600MM + filter wheel, it's been causing me a lot of trouble regarding tilt and bad stars. 

I tried to get around this by purchasing this item which claims to reduce the tilt, which it does, only very marginally compared to just three thumb screws. In the description of the item, it stated that it can be rotated with a counter ring. Although this does work, it doesn't hold it tightly enough and causes even more tilt than there already was, and again, probably something to do with the weight as I was very easily able to move the camera up and down.

I have three options to amend my situation.

1. I can try to think of something else to completely reduce the tilt enough for it to be acceptable. I was thinking of a baader clicklock but I've heard it doesn't work on the stock SW focuser

2. I buy a Moonlite CR2 focuser. Only issue I'm not sure about is the added weight of the focuser + the camera and filter wheel means that I won't be able to balance properly due to the focuser hitting the tube rings of the scope

3. I upgrade and buy something like an Esprit 80ED.

Saying this, I really do like the 130PDS. It's fast, has wide aperture and a decent focal length for a dirt cheap price. I also appreciate the challenges that comes with a newtonian and the rewards it reaps if everything goes right.

The item I tried: https://www.teleskop-express.de/shop/product_info.php/info/p5417_Lacerta-Thread-Adapter-for-using--Baader-MPCC-with-Skywatcher-Newtonians.html

Have you tried adjusting the focuser tilt?

[AstroMuni]

On 24/03/2014 at 00:24, Uranium235 said:

And another:

Amazing pics. Could you post the details of how you got the pictures as well pls.

[spillage]

3 hours ago, matt_baker said:

This scope has served me very well

 

Sounds like you need to make adjustments to the focuser as @Stub Mandrel has mentioned.

Shame it has not performed that well. I have been meaning to buy one for months now.

Edited July 21, 2020 by spillage

[cuivenion]

3 hours ago, Stub Mandrel said:

Have

Have you tried adjusting the focuser tilt?

Is there a guide to adjusting tilt in the 130pds focuser?

[Stub Mandrel]

1 hour ago, cuivenion said:

Is there a guide to adjusting tilt in the 130pds focuser?

 

There are three pairs of screws around the base of the focuser. Loosen the larger locking screw and tighten or loosen the small adjuster and re-tighten the locking screw.

If you do this with cheshire eyepiece you have eliminated tilt when it maintains collimation throughout the movement of the focuser. Tilt should show as the mirror centre spot drifting away from the middle of the view as you move the focuser over its whole range.

[cuivenion]

Thanks for that. I knew about the screws but I wasn't sure how you would measure the tilt.

[Jack Jack]

My first real attempt at astrophotography. Bought the 130PDS a few weeks ago but still have issues with collimation. After reading some of the above i'm now wondering if i too have a tilt issue. At first i thought it was just the coma so bought a MPCC Mk3 which helped but not across the whole field. Ill have to investigate a possible tilt issue using the advice above. Anyway, this is the first go i had with it, this image has no CC and was taken with a A7III all mounted on a HEQ5 Pro. Image consists of 36x 120 second lights, 30x flats and 50x Bias processed with SIRIL and finished in PS.

 

IG:https://www.instagram.com/astro_jack6

 

 

/

[Stub Mandrel]

On 21/07/2020 at 21:24, cuivenion said:

 measure the tilt.

You could use a depth micrometer or the tail end of digital calipers to measure how high the lip is compared to the surround. Obviously the paint finish will limit the accuracy.