Imaging with the 130pds

[Susaron]

Dear 130PDS addicts, herewith my first attempt in narrowband with an Optolong H Alpha 12nm coupled to the QHY168C. Taken yesterday with the Moon an a lot of jet stream with clouds from time to time, just a rough processing of 6 subs x 120s with bias at Gain 5 Offset 45 no guiding as EQMod did not want to work again.

Even for being 12 min I am quite happy with the camera sensitivity.

Cheers

[carastro]

Thought I'd post up on this thread the circumcision of my 130PDS

This is my focusser - in focus BEFORE 

I have been wanting to cut off some of the focusser for some time, but have neither the skills or tools to do it, and was nervous of making a pigs ear of it.  Recently I have got to know RolandKol (member on here) who has the same scope and has circumcised his own scope, and as he lives not too far from me kindly offered to come and do mine for me which he did last weekend.  Thanks Roland.

This is the defocussed star before and after, (very little clear sky last night, so after managing to get IN FOCUS, I wasn't able to take an actual image). 

the star shapes on bright stars I didn't like:

The new view down the OTA (I blackened the raw edge with black ink in case of reflections):

Just need some clear skies to test it out for real.  Also need to check point of focus with my other Atik camera and my DSLR.  Hopefully they won't be too different. 

The bit cut off:

Carole 

Edited April 15, 2018 by carastro
extra photo

[Susaron]

Dear 130PDS friends,

Herewith a reprocessing of the Rosette nebula, this time while learning PixInsight I did the correct process for Halpha subs, thus I extracted the Red channel only to follow the dedicated process recommended in Warren Keller´s book to process this kind of subs. It is a little bit forced, I still need to soft the background.

[Adam J]

On 15/04/2018 at 11:41, carastro said:

Thought I'd post up on this thread the circumcision of my 130PDS

This is my focusser - in focus BEFORE 

I have been wanting to cut off some of the focusser for some time, but have neither the skills or tools to do it, and was nervous of making a pigs ear of it.  Recently I have got to know RolandKol (member on here) who has the same scope and has circumcised his own scope, and as he lives not too far from me kindly offered to come and do mine for me which he did last weekend.  Thanks Roland.

This is the defocussed star before and after, (very little clear sky last night, so after managing to get IN FOCUS, I wasn't able to take an actual image). 

the star shapes on bright stars I didn't like:

The new view down the OTA (I blackened the raw edge with black ink in case of reflections):

Just need some clear skies to test it out for real.  Also need to check point of focus with my other Atik camera and my DSLR.  Hopefully they won't be too different. 

The bit cut off:

Carole 

Did you do anything to make sure that the draw tube can't be racked too far out of the tube and off the rear bearings? 

[Stub Mandrel]

Last night's Martkarian's Chain.

90% of 3 hours 30 minutes of 5-minute subs.

[vernmid]

Last nights Leo triplet

24 x 240s subs

130PDS + EQ5 + Unmodified 350d

PHD2 guided with ASI120MC

Pleased with this one :-)

 

Edited April 20, 2018 by vernmid

[Galen Gilmore]

15 minutes ago, vernmid said:

Last nights Leo triplet

24 x 240s subs

130PDS + EQ5 + Unmodified 350d

Pleased with this one :-)

 

is this guided? Just curious.

Great image BTW.

[vernmid]

Hi Galen, Yes guided with PHD2 and a ASI120MC :-)

Edited April 20, 2018 by vernmid

[carastro]

Quote

Did you do anything to make sure that the draw tube can't be racked too far out of the tube and off the rear bearings? 

No, Roland showed me that this could happen and showed me how to push the focusser back again if it does rack out too far.

I have just been to a local Astro camp for the last few evenings and got a chance to try out the 130PDS with both my atik cameras, and it does seem to be a marked improvement, I will post up the results when i have processed them.  I will just have to be careful not to rack the focusser out so it slips off the rollers.

It was also the first time I dared take the 130PDS to astro camp as I have always been worried about dew, but took the chance this time.  I did take the precaution of using an observatory tent and putting a couple of long dew heaters around the tube near the secondary.  I am not sure if either of these measures helped, but it seemed to be fine even without the dew shield I had made.

Carole 

 

 

Edited April 20, 2018 by carastro

[Stub Mandrel]

Last night: I accidentally did M95 and M96 instead of the triplet... lots of duff subs due to losing the faint guide star.

I have changed my workflow a lot, and combined with temperature matched flats I seem to be getting much less noise and much better star colour, although I could do with finding a nice colourful target and darker skies.

 

[Stub Mandrel]

53 minutes ago, carastro said:

No, Roland showed me that this could happen and showed me how to push the focusser back again if it does rack out too far

I glued a tiny square of printed circuit board material on as a stop.

[carastro]

Further to my post a few back about circumcising my 130PDS focusser.  This is the resulting star shape.

I am also pleased to report that this is the first time I have risked taking it to an Astro camp, as I had always been worried about dew.  I bought an observatory tent so the rig was inside that, and I took the precaution of wrapping a couple of long dew heaters around the tube by the 2ndry in case it helped (no idea if it made any difference), and I am pleased to report no problems with dew, I didn't even bother to use the dew shield I had made. 

Like the original poster of this thread, I am really starting to love my 130PDS.

Carole

[carastro]

Quote

I glued a tiny square of printed circuit board material on as a stop.

I did wonder about doing something like that, but had visions of it getting knocked off/falling off and falling down and hitting the secondary, so will just try to be careful about not racking it out too far. 

Carole 

[Susaron]

Last version of M81 M82 pair, after learning some tricks with Pixinsight, take a carefull look to the picture, as there are other 3 PGC type galaxies in the background, all Mag 15, it is amazing what this little imaging gem can do with only 2min subs.

 

[Uranium235]

Ummm guess what?

The 130 is sitting outside and collecting photons.... currently testing to see what happens when you push this telescope to its rayleigh limit

[Uranium235]

M81 - 36x120s (L) - shot with the ZWO ASI178MM (test camera)

Rough process only - and no flats applied.... brace yourself

Full frame:

Crop:

[RolandKol]

Fresh M51! Straight from DSS!
  Did it during this night and rapidly stretched a bit before leaving to office
Not a final job, as I still have some data from the night before.

Canon 1300D, 130PDS, SW CC, LP Filter and NEQ6.

ISO400-300sec, 4hours 6min in Total (simply left the scope shooting and went to sleep after Meridian adjustment)

APT with Dithering Enabled.
 

Initially, I wanted to try x2 Barlow on it, - a complete failure... I managed to get focus but had a very nasty coma... with and without SW CC...
any ideas how to fix it?

Edited April 23, 2018 by RolandKol

[Uranium235]

Now properly calibrated:

Still a bit noisy, but what do you expect for just over 1 hr exposure! Its alright, but its not a miracle worker...lol

BTW: This was shot at just beyond the Rayleigh limit of the telescope (0.85" p/p)

[Susaron]

10 hours ago, Uranium235 said:

Now properly calibrated:

Still a bit noisy, but what do you expect for just over 1 hr exposure! Its alright, but its not a miracle worker...lol

BTW: This was shot at just beyond the Rayleigh limit of the telescope (0.85" p/p)

New Benchmark for the 130PDS gents.

[Stub Mandrel]

10 hours ago, Uranium235 said:

Now properly calibrated:

Keep trying and you'll soon get the hang of it

 

Bodes well for the future...

Edited April 24, 2018 by Stub Mandrel

[alexbb]

I've one finished image too while others are in progress. I will replace this weekend the secondary mirror with a larger one and, perhaps, cut a bit off from from one side of the focuser.

Meanwhile, the finished image, in another thread and original.

https://stargazerslounge.com/topic/311677-m13-lrgb-with-130pds/

Clear skies!

[Gerry Casa Christiana]

11 hours ago, Uranium235 said:

Now properly calibrated:

Still a bit noisy, but what do you expect for just over 1 hr exposure! Its alright, but its not a miracle worker...lol

BTW: This was shot at just beyond the Rayleigh limit of the telescope (0.85" p/p)

Great shot. Can I ask how do you work out the Rayleigh limit for a given telescope. Go on tell me to get on my bike  Thanks Gerry

[alexbb]

5 minutes ago, Gerry Casa Christiana said:

Great shot. Can I ask how do you work out the Rayleigh limit for a given telescope. Go on tell me to get on my bike  Thanks Gerry

https://www.cloudynights.com/topic/1429-rayleigh-limit-dawes-limit/

[Uranium235]

27 minutes ago, Gerry Casa Christiana said:

Great shot. Can I ask how do you work out the Rayleigh limit for a given telescope. Go on tell me to get on my bike  Thanks Gerry

Use the telescope capability calculator found here:

https://astronomy.tools/

All you need to do is punch in the aperture size and it will tell you the limits for your telescope.

[Gerry Casa Christiana]

1 hour ago, Uranium235 said:

Use the telescope capability calculator found here:

https://astronomy.tools/

All you need to do is punch in the aperture size and it will tell you the limits for your telescope.

Ah that. The pixel resolution of camera and scope. Just lost me with the Rayleigh didn't realise that was the tee for resolution of the telescope.