Imaging with the 130pds

[Jamgood]

37 minutes ago, Andyy said:

130PDS came in today and looking good! Collimation is slighty off, but the collimation screws on the secondary are extremely tight (all three)!

Any tips to loosen them? Thanks!

Mine was the same when I got it. One of them will just need a bit more force to get it to shift. Once that one is done, the others will no longer be tight. 

[Andyy]

30 minutes ago, Jamgood said:

Mine was the same when I got it. One of them will just need a bit more force to get it to shift. Once that one is done, the others will no longer be tight. 

Is it necessary to loosen the center screw? What tool did you use for the collimation bolts?

I’m afraid to twist the spider vanes…

[Jamgood]

44 minutes ago, Andyy said:

Is it necessary to loosen the center screw? What tool did you use for the collimation bolts?

I’m afraid to twist the spider vanes…

I just used an Allen Key. I got my hand on the secondary as much as possible and held it while giving one of the bolts a twist. 

If you're confident enough to collimate the scope, you could try loosening the centre screw a little first.

[Andyy]

2 hours ago, Jamgood said:

I just used an Allen Key. I got my hand on the secondary as much as possible and held it while giving one of the bolts a twist. 

If you're confident enough to collimate the scope, you could try loosening the centre screw a little first.

Managed to get them out and replace them with Bobs knobs. Inital collimation done, now wait for clear skies for star test! Thanks @Jamgood

[Jamgood]

31 minutes ago, Andyy said:

Managed to get them out and replace them with Bobs knobs. Inital collimation done, now wait for clear skies for star test! Thanks @Jamgood

No problem. Bob's Knobs are a great addition to the scope.  I have them on mine also. Makes collimation of the secondary a much easier task. 

Edited October 5, 2021 by Jamgood

[alacant]

Hi everyone

After having had only a dim 72ed for the past weeks, it was nice to get something bright and lively once more.

Here are some clusters: ngc884 and ngc869 in Perseus. ngc1907 and m38 in Auriga.

Thanks for looking.

 

eos700d @ ISO800

l to r: ngc884 ngc869

 

top down: m38, ngc1907

[Bibabutzemann]

@alacant

Really beautiful pictures you got there. How do you get those stars so shiny and punchy 😮

Here is a result from last weekend: 

130PDS + EQ3 Pro + EOS 1200D (full spectrum mod + L2 Filter)

91x150s= 3h47.5min @ISO800

[Pitch Black Skies]

On 25/09/2021 at 21:58, D33P said:

My first image since picking up a 130pds. No a scratch on some of the images here, but I'm so happy with my new little photon collector. Looking forward to the next few months

 

Great picture!

I've noticed 6 diffraction spikes in your stars. Have you upgraded the spider?

[Skyline]

On 11/10/2021 at 10:20, alacant said:

Hi everyone

After having had only a dim 72ed for the past weeks, it was nice to get something bright and lively once more.

Here are some clusters: ngc884 and ngc869 in Perseus. ngc1907 and m38 in Auriga.

Thanks for looking.

 

eos700d @ ISO800

l to r: ngc884 ngc869

 

top down: m38, ngc1907

Nice processing, when zoomed in the brighter star shapes look triangle.

[alacant]

Hi everyone

UHC filter for this one. An attempt at HOO with blue in ST's NBAccents. The filter passes very little: we needed 10 minute frames to get anywhere near.

Thanks for looking and do post if you've any 130/dslr/uhc stuff.

eos700d: 15x10min @ ISO800

[Bibabutzemann]

Pleiades, 4 hours integration 

Equipment:

130PDS + EQ3 Pro + EOS 1200D (full spectrum mod + L2 Filter)

It is really challenging to process.

Normally i use Starnet++ to remove Stars, process the nebula and add stars later. This was literally impossible for me with this target

[Mycro]

My comma corrector arrived today. At this time of the year with this scope and a canon 2000d unmoded and without filters,  what would be your favourite targets to try out?

[Tan Zhi Qi]

On 14/10/2021 at 21:44, Bibabutzemann said:

Pleiades, 4 hours integration 

Equipment:

130PDS + EQ3 Pro + EOS 1200D (full spectrum mod + L2 Filter)

It is really challenging to process.

Normally i use Starnet++ to remove Stars, process the nebula and add stars later. This was literally impossible for me with this target

Awesome picture! What software did you use to process this image? Is it Photoshop or PixInsight? 

[Bibabutzemann]

1 hour ago, Tan Zhi Qi said:

Awesome picture! What software did you use to process this image? Is it Photoshop or PixInsight? 

Thank you! I use DSS+Siril+Photoshop

DSS for stacking

Siril for Background extraction, color calibration and some stretching

Photoshop for the rest

[alacant]

Hi everyone

This season's attempt at m45 whilst we still had use of the little 130. The aim was to try for a bit of that brownish coloured dust/fog you see all over Taurus. It's beginning to appear, but it's gonna need more frames to clean it and lose the noise. Just couldn't persuade myself to hit the denoise button. Yet...

eos700d en 130pds. Calibración y apilado: Siril. Procesado: StarTools 1.8.516

 

EDIT: added an further 10 x 300s frames. Looks like that's the limit. Can't see much improvement...

Edited October 17, 2021 by alacant

[Stuf1978]

Finally got round to giving the 130PDS a run out and have decided reflectors are a bit of a faff aren't they. I was intending to shoot the Wizard Nebula and thought I'd just set up as as normal and away I would go without issue, the scope had other ideas. I initially set up with an L-eXtreme filter but as I had no way of knowing where the focus point was I couldn't even find a star never mind focus. So I changed the filter for a UV/IR cut and changed tactics 😂

1. Balancing - this is a bit of a nightmare, I couldn't seem to get it nailed in declination. I thought I had it close at one point but the when slewing the mount (HEQ5 Pro) I'd hear the familiar sound of the gears grinding so the balance was obviously way off. I think I need to add more weight to the rear and get this sorted during the day before giving it another go. 

2. Star Shapes - These weren't great. I'm not sure if it's spacing or tilt.  I managed to grab 6x3 minute subs on M33 (ignore the lack of flats) to see what my stars looked like after I collimated the scope after it was delivered.  I suspect it's tilt (please correct me if I'm wrong) as the stars at the bottom of the frame were worse than at the top. I've included the image below with crops of each corner to show this. Would this compression ring help out in this case?:

https://www.firstlightoptics.com/adapters/astro-essentials-2-inch-compression-ring-adapter-for-sky-watcher-newtonians-and-72ed-refractor-m54.html

3. Diffraction/reflection pattern - This seems to be biased toward one side of the star (see centre crop). What's the cause of this? Although this doesn't look completely horrendous it will bother me so I would like to get it sorted if possible. I'm using the Baader CC for what it's worth. 

If I can get these issues sorted then I think it will be a great little scope as it seems to be a bit of a light bucket, so any help in getting these fixed would be appreciated.

Oh and I did manage to at least get an image of the moon out of the session so it wasn't completely wasted

200x0.001 second exposures stacked in Autostakkert and processed in Photoshop (ZWO ASI294C Pro)

Cheers,

Stu

[Jim Smith]

11 minutes ago, Stuf1978 said:

2. Star Shapes - These weren't great. I'm not sure if it's spacing or tilt.  I managed to grab 6x3 minute subs on M33 (ignore the lack of flats) to see what my stars looked like after I collimated the scope after it was delivered.  I suspect it's tilt (please correct me if I'm wrong) as the stars at the bottom of the frame were worse than at the top. I've included the image below with crops of each corner to show this. Would this compression ring help out in this case?:

I like your M33. It's a natural looking image, rather like what you might see through a biggish telescope. Did you use a coma corrector?

[Stuf1978]

7 minutes ago, Jim Smith said:

I like your M33. It's a natural looking image, rather like what you might see through a biggish telescope. Did you use a coma corrector?

Thanks, was more of a test rather than an attempt at a complete image. Yeah I used the Baader Mk III MPCC

[alacant]

1 hour ago, Stuf1978 said:

I'm using the Baader CC

Hi

Nice shot.

Here's the/our pragmatic approach to the Baader cc:

• There is tilt: tap a third hole on the focuser collar at 120º to the two existing screws. The flo adapter may help but still has only two screws, so still needs tapping. Push the camera-cc assembly hard up against the focuser collar whilst tightening each screw a tiny bit at a time until you're tight.
• The Baader cc has to be within 1mm of 58mm between the shoulder of the cc and the camera sensor. Yours looks a touch too close. It also has to be totally perpendicular to the optical axis. One good method to achieve this is to use a 4mm spacer e.g. the ring from a low profile 2" filter, having firstly of course, removed Baader's own attempt at spacing;) Other ccs are far more tolerant to both spacing and tilt.
• Or don't bother, stay as you are and just correct the stars in software;)

** If you're still in the grace period, it maybe worth considering exchanging the cc for the sw, gso or -best of all- the gpu. Discussion here. 

Cheers and HTH

Edited October 22, 2021 by alacant

[Stuf1978]

51 minutes ago, alacant said:

Hi

Nice shot.

Here's the/our pragmatic approach to the Baader cc:

• There is tilt: tap a third hole on the focuser collar at 120º to the two existing screws. The flo adapter may help but still has only two screws, so still needs tapping. Push the camera-cc assembly hard up against the focuser collar whilst tightening each screw a tiny bit at a time until you're tight.
• The Baader cc has to be within 1mm of 58mm between the shoulder of the cc and the camera sensor. Yours looks a touch too close. It also has to be totally perpendicular to the optical axis. One good method to achieve this is to use a 4mm spacer e.g. the ring from a low profile 2" filter, having firstly of course, removed Baader's own attempt at spacing;) Other ccs are far more tolerant to both spacing and tilt.
• Or don't bother, stay as you are and just correct the stars in software;)

** If you're still in the grace period, it maybe worth considering exchanging the cc for the sw, gso or -best of all- the gpu. Discussion here. 

Cheers and HTH

Thanks that's great info. I'll have a play about with the spacing some more and try and get an additional hole tapped and take it from there. 

I purposely avoided the SW CC as I wanted to retain the focal length but I wasn't aware there were other options. If I cant get it sorted I'll probably just sell the baader one and try one of the others. Ideally, I want stars like the ones in your M45 above..... just lovely 😍 

[Bibabutzemann]

12 hours ago, Stuf1978 said:

Finally got round to giving the 130PDS a run out and have decided reflectors are a bit of a faff aren't they. I was intending to shoot the Wizard Nebula and thought I'd just set up as as normal and away I would go without issue, the scope had other ideas. I initially set up with an L-eXtreme filter but as I had no way of knowing where the focus point was I couldn't even find a star never mind focus. So I changed the filter for a UV/IR cut and changed tactics 😂

1. Balancing - this is a bit of a nightmare, I couldn't seem to get it nailed in declination. I thought I had it close at one point but the when slewing the mount (HEQ5 Pro) I'd hear the familiar sound of the gears grinding so the balance was obviously way off. I think I need to add more weight to the rear and get this sorted during the day before giving it another go. 

2. Star Shapes - These weren't great. I'm not sure if it's spacing or tilt.  I managed to grab 6x3 minute subs on M33 (ignore the lack of flats) to see what my stars looked like after I collimated the scope after it was delivered.  I suspect it's tilt (please correct me if I'm wrong) as the stars at the bottom of the frame were worse than at the top. I've included the image below with crops of each corner to show this. Would this compression ring help out in this case?:

https://www.firstlightoptics.com/adapters/astro-essentials-2-inch-compression-ring-adapter-for-sky-watcher-newtonians-and-72ed-refractor-m54.html

3. Diffraction/reflection pattern - This seems to be biased toward one side of the star (see centre crop). What's the cause of this? Although this doesn't look completely horrendous it will bother me so I would like to get it sorted if possible. I'm using the Baader CC for what it's worth. 

If I can get these issues sorted then I think it will be a great little scope as it seems to be a bit of a light bucket, so any help in getting these fixed would be appreciated.

Oh and I did manage to at least get an image of the moon out of the session so it wasn't completely wasted

200x0.001 second exposures stacked in Autostakkert and processed in Photoshop (ZWO ASI294C Pro)

Cheers,

Stu

Nice images! I also struggle with elongated stars with the MPCC. 

I think you should first rule out the source of the tilting. 

Go to a star rich area with a bright star in the centre. (For example Deneb)

Make sure to tighten the screws while pressing the cam against the focuser.

Now use the bright star and a Bahtinov mask to achieve perfect focus. Take an image .

Now rotate the camera by 180° and make sure to focus again. Take an image.

Now compare those images (with same orientation, to avoid confusion)

 

Case A : The same stars are stretched -> The tilting happens inside your telescope (Either focuser, secondary mirror or primary mirror).

This probably means you have to "just" collimate your scope. (I say probably because it could still be tilt due to a poor attachment between focuser and CC and its just coincidence, that you get this result. To be sure, just rotate again by 180° and see if still the same stars are misshapen.)

Assuming your 2nd mirror is descently collimated, you could first try to adjust the primary mirror while still having the bright star in the centre of your image in live view. Turn the screws so that the stars wanders in the direction, where you have more elongated stars. 

Then focus again and take a picture. Repeat those steps until the elongated stars are similar on all corners (or perfect in all corners  ). 

Now you can worry about perfect spacing. Try with different spacing rings on a similar target with a bright star in the middle many stars around.

I cant stress enough how important it is, to refocus everytime you touch your focuser. Otherwise it will mess up with your findings (Speaking from experience..)

 

Case B : The elongated stars are now in the opposite side -> This means the tilting happens at the CC or in the camera.

This could mean its due to poor attachment. 

If you still get the elongated stars on the opposite site, no matter how carefully you attach it, the tilting is inside of your CC, inside of your camera or at the attachment between camera and CC.

First thing i would do now is to lend a DSLR from someone and see how the CC works there.

 

Case C : Stars are now somewhere completely else elongated -> tilting is probably caused by poor attachment. (Those two screws are not very reliable as @alacant already pointed out.)

If you still have assymmetrical elongated stars after you ruled that out, you could now test if its Case A or B

 

 

I hope this helps. 

Good luck and CS, Patrick

 

PS: i know in my pictures above its not perfect, but its good enough for me to dont care. 

Altough, right after if went through this procedure (Mix of Case A and C) i got the following result

Edited October 22, 2021 by Bibabutzemann

[Bibabutzemann]

My latest Andromeda, had to throw away 1.5hours of integration due to windy conditions. My smol EQ3 doesnt like that at all

Now its only 2.6 hours, but im still happy with it.

Equipment: 130PDS + EQ3 Pro + EOS 1200D (full spectrum mod + L2 Filter)

Integration time: 63x150s @ISO 800

 

Edited October 22, 2021 by Bibabutzemann

[Stuf1978]

24 minutes ago, Bibabutzemann said:

Nice images! I also struggle with elongated stars with the MPCC. 

I think you should first rule out the source of the tilting. 

Go to a star rich area with a bright star in the centre. (For example Deneb)

Make sure to tighten the screws while pressing the cam against the focuser.

Now use the bright star and a Bahtinov mask to achieve perfect focus. Take an image .

Now rotate the camera by 180° and make sure to focus again. Take an image.

Now compare those images (with same orientation, to avoid confusion)

 

Case A : The same stars are stretched -> The tilting happens inside your telescope (Either focuser, secondary mirror or primary mirror).

This probably means you have to "just" collimate your scope. (I say probably because it could still be tilt due to a poor attachment between focuser and CC and its just coincidence, that you get this result. To be sure, just rotate again by 180° and see if still the same stars are misshapen.)

Assuming your 2nd mirror is descently collimated, you could first try to adjust the primary mirror while still having the bright star in the centre of your image in live view. Turn the screws so that the stars wanders in the direction, where you have more elongated stars. 

Then focus again and take a picture. Repeat those steps until the elongated stars are similar on all corners (or perfect in all corners  ). 

Now you can worry about perfect spacing. Try with different spacing rings on a similar target with a bright star in the middle many stars around.

I cant stress enough how important it is, to refocus everytime you touch your focuser. Otherwise it will mess up with your findings (Speaking from experience..)

 

Case B : The elongated stars are now in the opposite side -> This means the tilting happens at the CC or in the camera.

This could mean its due to poor attachment. 

If you still get the elongated stars on the opposite site, no matter how carefully you attach it, the tilting is inside of your CC, inside of your camera or at the attachment between camera and CC.

First thing i would do now is to lend a DSLR from someone and see how the CC works there.

 

Case C : Stars are now somewhere completely else elongated -> tilting is probably caused by poor attachment. (Those two screws are not very reliable as @alacant already pointed out.)

If you still have assymmetrical elongated stars after you ruled that out, you could now test if its Case A or B

 

 

I hope this helps. 

Good luck and CS, Patrick

 

PS: i know in my pictures above its not perfect, but its good enough for me to dont care. 

Altough, right after if went through this procedure (Mix of Case A and C) i got the following result

Thanks, that's a great set of instructions, very clear. I'll try it on the next cloudless night and report back. If I can get stars like yours I'd be very happy.

I've got a couple of dslrs so can try it with different cameras as well and hopefully pinpoint where the problem lies. 

On a side note, I've drilled and tapped the locking ring and added another thumbscrew which can only help 😁

Thanks

Stu

[Stuf1978]

29 minutes ago, Bibabutzemann said:

Nice images! I also struggle with elongated stars with the MPCC. 

I think you should first rule out the source of the tilting. 

Go to a star rich area with a bright star in the centre. (For example Deneb)

Make sure to tighten the screws while pressing the cam against the focuser.

Now use the bright star and a Bahtinov mask to achieve perfect focus. Take an image .

Now rotate the camera by 180° and make sure to focus again. Take an image.

Now compare those images (with same orientation, to avoid confusion)

 

Case A : The same stars are stretched -> The tilting happens inside your telescope (Either focuser, secondary mirror or primary mirror).

This probably means you have to "just" collimate your scope. (I say probably because it could still be tilt due to a poor attachment between focuser and CC and its just coincidence, that you get this result. To be sure, just rotate again by 180° and see if still the same stars are misshapen.)

Assuming your 2nd mirror is descently collimated, you could first try to adjust the primary mirror while still having the bright star in the centre of your image in live view. Turn the screws so that the stars wanders in the direction, where you have more elongated stars. 

Then focus again and take a picture. Repeat those steps until the elongated stars are similar on all corners (or perfect in all corners  ). 

Now you can worry about perfect spacing. Try with different spacing rings on a similar target with a bright star in the middle many stars around.

I cant stress enough how important it is, to refocus everytime you touch your focuser. Otherwise it will mess up with your findings (Speaking from experience..)

 

Case B : The elongated stars are now in the opposite side -> This means the tilting happens at the CC or in the camera.

This could mean its due to poor attachment. 

If you still get the elongated stars on the opposite site, no matter how carefully you attach it, the tilting is inside of your CC, inside of your camera or at the attachment between camera and CC.

First thing i would do now is to lend a DSLR from someone and see how the CC works there.

 

Case C : Stars are now somewhere completely else elongated -> tilting is probably caused by poor attachment. (Those two screws are not very reliable as @alacant already pointed out.)

If you still have assymmetrical elongated stars after you ruled that out, you could now test if its Case A or B

 

 

I hope this helps. 

Good luck and CS, Patrick

 

PS: i know in my pictures above its not perfect, but its good enough for me to dont care. 

Altough, right after if went through this procedure (Mix of Case A and C) i got the following result

Great M31 😎

[BrendanC]

Hi all,

Thought I'd add this - an unusual target - 30 Cyg and 31 Cyg A & B.

30 Cyg, to the right of the image, is a white giant star with a blue tint.

31 Cyg A is a bright orange giant, with a smaller blue companion called 31 Cyg B (alternatively HD 192579). They are a binary system which orbits at a distance of a mere 11 astronomical units. As they are viewed side-on, every 10.32 years they are are in eclipse for 63 days.

Image details:
* 1:10 hours of integration at ISO800 from 70x60s subs
* Bortle 4, Moon 100% phase, 47° height
* 25 flats, 25 dark flats, 50 darks
* Sky-Watcher 130PDS with primary baffle, NEQ6 with Rowan belt, EOS1000D minus IR filter, 0.9x coma corrector, APT, PHD2, DSS, StarTools, Topaz DeNoise AI

 

Cheers, Brendan

 

 

Edited October 25, 2021 by BrendanC