Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_android_vs_ios_winners.thumb.jpg.803608cf7eedd5cfb31eedc3e3f357e9.jpg

Russe

Imaging with the 130pds

Recommended Posts

Looks more like you need a little more spacing on the corrector to me. Maybe try 56mm back focus.

Share this post


Link to post
Share on other sites

Update: Luckily enough, the sky was clear tonight, although the seeing was horrible, I managed to test out the star field. All I can say is thank you to Matt, problem is resolved ūüôā.

Share this post


Link to post
Share on other sites
1 minute ago, JamesAstro2002 said:

Update: Luckily enough, the sky was clear tonight, although the seeing was horrible, I managed to test out the star field. All I can say is thank you to Matt, problem is resolved ūüôā.

No problem, happy to help :)

Share this post


Link to post
Share on other sites

Hi everyone

First image from the new observatory and replacement telescope setup.

Still a little work needed in regards to equipment spacing etc... but was really good to get everything up and working.
looking at the image I think I need to reduce the spacing between the mpcc and ccd if anyone can help confirming this that would be great

M33 - Triangulum Galaxy

Total imaging time = 48 minutes

Skywatcher HEQ5, Skywatcher 130PDS, QHY8L, OVL OAG+QHY5II-M.

1506892513_M33TriangulumGalaxy.thumb.jpg.5729a8ca56cb4dcd76517f9adb55d47a.jpg

  • Like 5

Share this post


Link to post
Share on other sites

How much spacing have you got between the sensor and the mpcc? It should need about 34.8mm

Share this post


Link to post
Share on other sites
1 hour ago, matt_baker said:

How much spacing have you got between the sensor and the mpcc? It should need about 34.8mm

The OAG is around 15mm, the sensor flange distance is 20.2 which leaves around 22.3 to make up the 57.5mm spacing requirement for using the M48 threads from what I understand.
This I have set to a close as possible (within .5mm I would say) I am going to have to double check again however

Share this post


Link to post
Share on other sites
1 minute ago, matt_baker said:

Is it not supposed to be 55mm spacing for the MPCC?

I always thought it was however looking at other diagrams show it as 55mm using the T2 threads and 57.5mm using the M48 threads.
If it is indeed 55mm that will make life a lot easier trying to get the OAG par-focal as well, currently the guide camera is stripped down to the bare sensor to allow enough adjustment.

Share this post


Link to post
Share on other sites

Its been a very long time.... perhaps too long..lol.

20x450 Ha on the Veil, starting off on something easy. No calibration either. I'll probably process it again later on when I remember what it is I used to do :D

Veil_final_100.thumb.jpg.a60bdc12133ff45d9e20de421cb6a713.jpg

  • Like 5

Share this post


Link to post
Share on other sites

Last Tuesday, I managed to go out and image M13 just fine, with only a couple of stars in one corner being elongated due to my focuser tilt.

Last night however, I was trying to image the Iris nebula and the stars looked awful.

I made sure to collimate and make sure the focuser screws were tightened nicely. Although I did push the mirror up slightly with the collimation screws to try and minimize the drawtube obstruction.

Collimation was done with a cheshire eyepiece and collimation cap.

My focus was also good from my bhatinov mask.

I think I know it's not caused by differential flexure, since the stars look awful even from a 5 second exposure which I've uploaded for all to see.

Could anyone help me out?

Single__0296_ISO800_5s__NA.jpg

Share this post


Link to post
Share on other sites
On 26/08/2019 at 20:11, matt_baker said:

Last Tuesday, I managed to go out and image M13 just fine, with only a couple of stars in one corner being elongated due to my focuser tilt.

Last night however, I was trying to image the Iris nebula and the stars looked awful.

I made sure to collimate and make sure the focuser screws were tightened nicely. Although I did push the mirror up slightly with the collimation screws to try and minimize the drawtube obstruction.

Collimation was done with a cheshire eyepiece and collimation cap.

My focus was also good from my bhatinov mask.

I think I know it's not caused by differential flexure, since the stars look awful even from a 5 second exposure which I've uploaded for all to see.

Could anyone help me out?

Single__0296_ISO800_5s__NA.jpg

If you look closely at the corners, it will tell a story. The left side has normal coma (I assume youre using a corrector?), while the right  is a different type of distortion (radial).

That would indicate some tilt, either in the focuser, the way the corrector sits in the drawtube, or whether you have any loose connections. You might need to take time to square your focuser, simply tightening up all the screws doesnt quite mean that its pointing at the right spot on the tube wall.  You have to remove the secondary and put in a marker for where the focuser tube should be pointing. There is stuff on youtube how how to do this, but I wouldnt attempt it until you have the bits required (digital calipers etc..)

The stars in the middle are a bit so-so, but you didnt state whether you were guiding or not.

Share this post


Link to post
Share on other sites
Posted (edited)
2 hours ago, Uranium235 said:

If you look closely at the corners, it will tell a story. The left side has normal coma (I assume youre using a corrector?), while the right  is a different type of distortion (radial).

That would indicate some tilt, either in the focuser, the way the corrector sits in the drawtube, or whether you have any loose connections. You might need to take time to square your focuser, simply tightening up all the screws doesnt quite mean that its pointing at the right spot on the tube wall.  You have to remove the secondary and put in a marker for where the focuser tube should be pointing. There is stuff on youtube how how to do this, but I wouldnt attempt it until you have the bits required (digital calipers etc..)

The stars in the middle are a bit so-so, but you didnt state whether you were guiding or not.

Yes, I'm using a Badder corrector and yes, I was guiding but this was a 5 second sub, and I doubt guiding would affect the stars at this time frame surely.

I'll go see how to amend this

I remember I did adjust my spider vanes my quite a bit the first time I collimated with a cheshire and never checked to see if they were centered properly or not. Maybe this could be a cause?

Edit: Also, what kind of tap would I need for a third thumbscrew and how would I go about doing it, if you don't mind me asking?

Edited by matt_baker

Share this post


Link to post
Share on other sites
On 26/08/2019 at 10:27, Uranium235 said:

Its been a very long time.... perhaps too long..lol.

20x450 Ha on the Veil, starting off on something easy. No calibration either. I'll probably process it again later on when I remember what it is I used to do :D

Rob... you really get all your amazing pictures with the ASI178MM cool?

Share this post


Link to post
Share on other sites
1 hour ago, Stub Mandrel said:

Rob... you really get all your amazing pictures with the ASI178MM cool?

FOV looks too big for it to be the ASI178mm cool but I may be proved wrong when Rob replies. 

Share this post


Link to post
Share on other sites
Posted (edited)

Went back for another reprocess at M13.

Deconvoluted the stars this time, changed colours and cropped it down slightly

Some of the noise still bothers me but that's what you get when you image with a DSLR uncooled. Might aim for some more time on it when I can.

What does everyone think?

 

Matt

 

Image03.jpg

 

More upclose look at the core:

Image030.thumb.jpg.43fd3ffaa1d81891670c331755fa8abe.jpg

Edited by matt_baker
  • Like 2

Share this post


Link to post
Share on other sites
7 hours ago, matt_baker said:

what you get when you image with a DSLR uncooled

Hi

Great image.

I don't think it's a limitation. Maybe it just needs denoising? There's not a lot to work with on the .jpg but with the .tif, you should be able to flatten the background completely. I had a go...

Cheers and HTH. 

 

 

13.jpg

Share this post


Link to post
Share on other sites

Lovely globular cluster

My first stack with my 130pds on my heq5 of M27. 

A bit noisy because of iso 1600. Also bad shaped stars because of the sw coma corrector. Need to chomp the draw tube off a bit. 

Dumbell1FIN.jpg

  • Like 1

Share this post


Link to post
Share on other sites
Posted (edited)
6 hours ago, alacant said:

Hi

Great image.

I don't think it's a limitation. Maybe it just needs denoising? There's not a lot to work with on the .jpg but with the .tif, you should be able to flatten the background completely. I had a go...

Cheers and HTH. 

 

 

13.jpg

I think it also depends what kind of monitor you're viewing it from.

I have a crappy TN panel on one of my monitors that's bad at reproducing especially blacks, however on my IPS, it looks flawless so I'm not sure

What did you use to reduce the noise?

Edit: I think I've fixed it by lowering the background with curves

 

Image033.thumb.jpg.d2debc760b424c2786f3ef535d31475f.jpg

Edited by matt_baker
  • Like 1

Share this post


Link to post
Share on other sites
5 hours ago, matt_baker said:

I've fixed it

That's good. You could try wavelet denoise: GIMP.

Cheers

Share this post


Link to post
Share on other sites
37 minutes ago, Shaun_Astro said:

Bit over stretched, but a hour and a bit on m31. Dew ruined half my subs! 

Looks good, maybe a touch green on my monitor? Hope you don't object, I hit a grab of your image with HLVG (Hasta La Vista Green plugin) in Photoshop:

image.png.2cd03deacdd1523a2b019bc61d2dbd4f.png

Edited by Stub Mandrel
  • Thanks 1

Share this post


Link to post
Share on other sites
1 hour ago, Stub Mandrel said:

Looks good, maybe a touch green on my monitor? Hope you don't object, I hit a grab of your image with HLVG (Hasta La Vista Green plugin) in Photoshop:

image.png.2cd03deacdd1523a2b019bc61d2dbd4f.png

Much better thank you! 

  • Like 1

Share this post


Link to post
Share on other sites
3 hours ago, Shaun_Astro said:

hour and a bit on m31

Andromeda2.thumb.jpg.1f58f2f3cd2882919b6addc16d014b56.jpg

 

Excellent shot. I had a go at the stars...

  • Like 1

Share this post


Link to post
Share on other sites

AndromedaGalaxyFinalHDRCrop.thumb.jpg.3fd2d47c82b589dbc002511c02bc038a.jpg

3 Hours of data on Andromeda with the 600D from last night.

I noticed that I seem to have them oddly shaped stars again. Last time, I fixed this by undoing the primary mirror retention clips a bit as they were tight up against the mirror. Now that i've been able to get back out for a night of imaging, they're back again! Any ideas as to why this could be ? I double checked the clips again and they're still loose, although they are still touching the mirror, are they supposed to touch it or not? I also made sure that the primary collimation locking screws aren't overly tightened. Also, through my cheshire, collimation looks to be spot on.

  • Like 4

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By jadcx
      Skywatcher 80 ED DS-Pro outfit including matched flattener and motor focus £550
      This kit gives you a great introduction to astronomy and imaging, which is why it's so popular.  You can see details over at FLO but there is:
      80 ED Ds-Pro OTA (Objective Lens Diameter: 80mm, Telescope Focal Length: 600mm,  f/7.5)
      SW Eyepiece (2"): 28mm
      2‚ÄĚ/50.8mm Di-Electric Star Diagonal
      9x50 Finderscope
      Dual-Speed 11:1 2‚ÄĚ Crayford Focuser (Backlash-Free)
      Supplied with Tube Rings & Mounting Plate - please note there is a longer black vixen type dovetail fitted, not the fancy new green short one you will see on the FLO site
      SW motor focus and fitting kit - I've never used this, hence it's not fitted (more details over on FLO)
      Dedicated SW 0.85x reducer/flattener (see FLO for more details)
      Aluminium Carrying / Shipping Case
       
      The RRP is over £720, so grab a bargain while you can.
      Collection from Nottingham, or DHL for £20 (within UK)



    • By GiovanniF
      Hi to everyone, I used to do some astrophotography in the past with a Celestron AVX and DSLR but after few month had to give up for several reasons, including light pollution (I'm living in zone 3 east London), and also working shifts. Now I want to start again, and this time more serious. I've been searching around for a couple of months to choose all the gear and I'm quite happy with the list so far although it's a bit over the price I planned at first.
       I will get an William optics Z73 with his 50mm guide scope, a flattener/reducer 0.8, light pollution filter IDAS D2 and as camera I will use a Canon 600D modded and I will buy a ZWO 183MC Pro, after so much research, I'm very happy with the scale and framing I will get with this combo, but I'm starting to get confused with the mount.
      My first idea was to go for an HEQ5 Pro, as my previous experience with the AVX has been awful, then I realized that the FLO, sells that mount with belt modification and also some cleaning and tuning if required, I heard that it's a big improvement over the stock one and the price it's ok, but another important factor for me it's portability. Unfortunately, my garden doesn't allow me to do much so I will need to carry around on trolley, for a km walk, I'm a strong person and been doing plenty of time with the AVX, so my confusion came recently when the iOptron mounts entered my radar. I start comparing the heq5 pro with belt, with the iOptron cem25EC and the CEM40 without encoders, and I'm so unsure of which to buy, the cem25 seem to be the equivalent of heq5 at least speaking of payload, but in some threads I read people saying it's a bit fragile so kind of remove it from the equation although the weight it's interesting for my situation, then the cem40, seem to be quite similar on weight to the heq5 but with higher payload and that's interesting too as I will buy a C11 at some point.
      Now it will all come down to the accuracy of tracking I guess, how the heq5 and cem40 would compare on tracking and guiding? If the cem40 it's better, I would probably go with that since it holds more and would last longer as I don't plan to get anything bigger than a C11, but if the skywatcher it's better, I could decide to go for that, and when I move to a place with better garden then get a second mount with higher payload.
      Apologise for the long post and my english.
      Kind Regards,
      Giovanni. 
    • By Andy Cole
      Hi all
      I'm a newbie here but not totally new to astronomy. I've had a telescope since I was a teenager (over 30 years!) and only ever had 1 telescope - a Tasco 40x40mm reflector. I expect members my age are familiar with it - thin and white with a thin metal tripod and a push and pull focuser.  It's still functional at more than 30 years old although the thread on the eyepiece is worn so the eyepiece falls off regularly! I've only ever used it to look at the moon, Jupiter and Saturn and that's always been good enough for me.  Now I have been thinking of getting a new scope. I have a very limited budget and so I am wondering whether I will get any significant improvements on what I can see.
      My earliest memories of the Tasco from childhood were that I could see the rings of Saturn as a line across the circle of the planet.  Having rekindled my interest in the last few years, I have started to use it again, and nowadays, when Saturn is visible, I can clearly see the rings 'as a ring' and the gap between the planet and the rings, which I don't remember seeing as a kid. 
      Vieing Jupiter I can usually see about 4 moons.
      I've heard that the Skywatcher Heritage 130P Dobsonian is a good 'budget' telescope, and great for casual use, which is what appeals to me most.  I don't want a telescope with complicated setup or one that takes up a lot of space.  TheSkywatcher seems to fit the bill, and it also fits my very limited budget.
      What I am most interested to find out is whill I get an improved view of the things I have already experienced?  I have read some reviews that describe what you can see with this scope and it sounds like it's pretty much what I can already see. And it's maximum 65x magnification doesn't seem like much better than the Tasco's 40x. But will the wider aperture make a bigger difference than the magnification?
      I'm also interested to know if I could use this scope for basic astrophotography - I have numerous cameras - phone cameras, compacts and DSLR's (photohraphy is my main hobby).  I'm not talking about hour long exposures of dark sky objects, just what can be seen easily through this scope.
      I'd love to know what people's opinions are, especially if you own or have used this scope.  I'm also interested to hear recommendations for other scopes, but please remember I have limited budget and space.  I know that an 8" or more is better and I would love one but they are just too expensive and too large for me.
      Cheers
      Andy
    • By Mark Daniels
      Been looking for neat solution to taking small scope abroad using my stuff and not paying out for a dedicated set up. 
      Have a skywatcher finder which with a barlow and 90 * gives good results. I was looking at an Orion mini eq tabletop tripod but hard to get hold of. 
      Play a bit of music in a band and have a few microphone stands so got to work with a hack saw. 
      I used a mic holder as in photo they are about £3 and cut the holder part off and filed flat. Drilled hole through to accept large camera thread (£3 screw bolt)
      this allows shortened micstand to fit to the alt az mount. (Mic stand 15 of ebay. )
      the dovetail was expensive as i wanted green and got from germany £30 with couier the white finder bracket from tring harrisons £6
      so thats £60 but if i went for black dovetail less than £40  seeing i had mic stand already quite a cheap solition
      the stand is very stable and provided the telescope is moved clockwise when rotating freehand the threads stay tight  with the fine controls either direction works well
      overall wiegt is bit over 3 kg and will fit in a standard aluminium camera case 
      hope this if useful 
      MarkūüĎć
       







    • By Lachlan
      Hi everyone, 
      as the title suggests, I've noticed that the RA axis of my HEQ5 pro mount has some give. I don't notice it while the clutch is unlocked, but it's very obvious with a locked RA clutch. Any suggestions on what could be causing it/what adjustments need to be made? 
      Thanks 
√ó
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.