sagramore

15 hours ago, Whistlin Bob said:

Always a bit tricky imaging under a bright moon, but even more so when you’re in clumsy mode. Last night I managed to disconnect the power from my mount whilst aligning. Twice! Then I dropped an eyepiece by slewing the scope without having it fixed properly (fortunately it landed on the rubber eye cup). Finally I spent ages trying to work out why I couldn’t focus my guide-scope until the penny finally dropped that I was twiddling with the locking ring and not the focuser. So I’m taking this picture as a victory of the scope over its owner!

15x 10 min subs – Canon 600d – 130 pd-s- 7nm Ha filter.

 

*IMAGE*

I wish my nights of "getting things a bit wrong" still ended in such a lovely image! Usually I just have cold hands and frustration to take to bed with me....

On 09/12/2018 at 21:08, jjosefsen said:

I often have very high relative humidity 90+.. with my frac and a dew band it's not an issue, but it worries me with the open design of a newt.

I must admit I was hoping I didn't have to cut the draw tube with the cc I'm looking at.

Can anyone tell me the diameter of the stalk the secondary mirror is mounted on?

I would add that you can avoid cutting the draw tube if you are willing to modify the scope to move the primary mirror up the tube a little. There are a couple of us in this thread that did it - it's a reversible modification and works perfectly to bring the focal plane out so the draw tube doesn't protrude into the aperture too much. Sorry I can't find the exact posts but if you are able to search (or scroll through!?!) this thread then at least 2 of us have photos and descriptions of how we did it.

Just a thought!

On 03/12/2018 at 13:08, rotatux said:

Hello fellow 130PDS imagers

I've processed these subs of Pleiades taken during last country holidays.
It turns out much better than my previous successful try at it, more smooth, still good colors and much more structure.

My problem is I've developped two versions of it:
* One with moderate stretching, which IMO preserves colors better (especially that Pleiades' electric blue I like so much), and still shows structure on good monitors
* Another where I pushed streching more, to ease showing on less good monitors, but it find it faded colors a bit and eventually I have mixed feeling about it.
I'm looking for others' opinion/preference/advice about which one to keep, or is more generally acceptable, as myself having good monitors at home I prefer the first one.

 

 

Thanks for looking.

I very much like the right-hand image (harder stretch) as the extra detail for me is worth a lot more than the slight changes in colour. They are both lovely though!

So I hope this kind of post is allowed and I'm not seen to be spamming!

I have recently done a lot of re-processing of old data using the advice of people in here. The main difference is having obtained Astronomy Tools v1.6 for Photoshop and matt_baker's advice to touch up in Lightroom as a final step. I think it shows quite a leap in the quality of the images and also made me realise just how much skill there is involved in the post-processing of the data (even more so when the data is as dodgy as mine often is... haha).

Anyway, these are all taken using the 130PDS and an unmodified Canon 550D DSLR. They are all using 300 s guided subs (with dithering) via APT and PHD. I hope you like them. I'm quietly pleased with myself

M31 Before:

M31 After (also with a bit more data added, so not perhaps a 100% direct processing comparison):

M42 Before:

M42 After:

M51 Before:

M51 After:

EDIT TO ADD: I also have some old data of M1 and of M81/M82 however the new processing hasn't been quite as successful yet. I still need some more attempts at those before I share again! 

9 hours ago, Susaron said:

I will be very gratefull if you could post a picture or screenshot with the parameters you use in APT to control dithering.

Here you go! I am not an expert at all but once everything's guiding with PHD2 I have these settings in APT and set it to dither every 2 images. It seems to work for me at least. I also use a 60 second gap between exposures in APT because I used to have some problems with the dither step taking a while, but I'm not sure if that's overkill or not. It usually doesn't make too much difference when I'm on 300 second subs though so I've left it that way.

4 hours ago, Susaron said:

I will be very gratefull if you could post a picture or screenshot with the parameters you use in APT to control dithering.

Hi Susaron - I'm at work at the moment but I'll try and get the settings from my laptop when I get home tonight. 

So, I added some more time and had about 5 different attempts at stacking & processing various combinations of my data. I also got hold of Astronomy Tools v1.6 for Photoshop and took matt_baker's advice on final tweaks in Lightroom.

All in all I'm quite pleased with this considering my inexperience and the (I think) quite poor raw data I had (lots of LP, high cloud, etc.).

Thanks for the encouragement and help on this forum guys!

Messier 31 (Andromeda Galaxy) with Messiers 32 and 110
2018-10-30 & 2018-11-02, Didcot, England
 

Gear:
Skywatcher 130-PDS with 0.9x coma corrector (585 mm, f/4.5)
Skywatcher NEQ6-Pro Synscan
Canon EOS 550D (unmodified) and Skywatcher 2" LP filter
ZWO ASI120-MC guide camera
Skywatcher Startravel 80 guide scope

Acquisition & Processing:
- AstrophotographyTools (APT) and PHD2 guiding with dithering
- 34 x 300s = total 170 minutes @ ISO 800
- 2x20 flats, 16 library darks, library bias
- Stacked in DeepSkyStacker and post-processed in Photoshop CC 2018 (with Gradient Xterminator + Astronomy Tools v1.6)

Well, I had another try.

It seems that my poor framing and high level clouds caused me problems when processing again. I will have to keep persevering.

What I will say is that I have at least improved upon the first try! This is now a total of 120 minutes (30 from previously, and 90 from tonight) and the tutorial & tools helped a lot. I think I might've overdone it a bit to try and get more dust though....

I also tried with just 90 minutes from tonight and I think I really overprocessed this one but there is more detail in the extremities.

These are both stacked without darks, so I might try again with the darks sometime this weekend and see if it helps or not.

Amazing results!

Also, I just watched that tutorial/walkthrough and have immediately bought Noel Carboni's PS actions (can't believe I didn't have them before!) and once I have (hopefully) more data from tonight, I will be giving my data a full reprocessing using the help there.

Thanks again!

Just now, matt_baker said:

For 60 minutes that seems like a great result. If it helps I used this tutorial to process mine

http://www.myastronomyjournal.com/DSLR-AIP/C002-M31-Walkthrough/

Thanks, I will take a look!

I did a test with this data actually - one stack with darks from my darks library, and one without darks. I actually found little to no difference, and possibly even lower noise (very slightly) in the stack without darks. I do dither quite hard after every second sub though, so that's probably why. I am starting to lean away from worrying much about darks at ISO800, although perhaps they're more important at higher ISOs?

4 minutes ago, matt_baker said:

I did actually waste about 30-40 minutes after realising the guiding was failing and trails were everywhere near the time of the meridian flip. Once I had sent a slew command on EQMod, I then had to take time re-centering as best as I could in the frame before continuing. I guess we can't have everything. I would've spent the extra time gathering a few more darks to lower the noise further

Yeah, I basically did similar. Everything was set up and working perfectly and the clouds finally went away. I left it to do it's thing thinking it would auto-meridian flip, I came back after 1hr to find it was just stuck at the maximum of the meridian and hadn't flipped, so I lost bout 1 hr of acquisition!

I sorted it out, did like you said - reframed as best I could without taking ages over it (I am still awful at framing, something to improve on) - and then after another few subs my secondary fogged up.....

I would say I don't know why we put ourselves through it, but I was still quite happy with what I got out of 60 mins of data.... I will share it actually, but hopefully so I can show the improvements later tonight!

EDIT TO ADD: I think my colour balance is totally off, and I think this comes from my stacking settings. So that's something I need to work out. I either end up with something that's got a strong hue across the whole image, or I get something with a lack of any colour at all (like this one above). More practice I guess!

3 minutes ago, matt_baker said:

Took this last night and processed it this afternoon.

130PDS

HEQ5 Pro

Nikon D3200

120MC with 50mm Guide Scope

Badder mk.iii coma corrector

24x300s Lights with 7x120s and 5x60s for the core

5 Darks for each

25 Bias and 25 Flats

PHD 2 and EQMod for controlling and guiding

Stacked in DSS

Processed in Photoshop CC 2015

This is the first time I've ever attempted Andromeda and I'm very pleased with the result

I might possibly grab a couple hours of more data in the future due to the noise which I tried my best to minimize in PS using Astronomy tools action set

 

*ANDROMEDA*

Very nice!! A really nice shot that one, I think you've done it justice.

I just saw your post from Wednesday and I was about to post my attempts from the same evening but I was plagued by clouds, a failed meridian flip, and then dew so I only managed 1 hr of exposures. I also think my processing is bad so I will hold off posting my poor attempt for now as it is way worse than yours  We have really similar equipment by the looks of it.

I am hoping to grab a couple more hours on it tonight if the weather holds out though, so watch this space!

EDIT: Can I ask what your stacking parameters in DSS are for this? I am shooting the same length subs with a Canon 550D (T2i) and I think my stacking isn't optimal either. Any advice is appreciated.

I've not needed one for the 130-PDS yet! I am sure it'll happen one day though and I will be unprepared....

On 27/12/2017 at 16:40, Galen Gilmore said:

I guess that is possible, but would it really take such a huge bite out of the star?

I'm afraid it can do, yes! That's why so many in here have modified their scopes to fix it. There's destructive ways (sawing, etc.) and non-destructive ways (extension screws to bring the mirror up the tube) and none of them are too difficult. Lots of guides/advice/photos on earlier pages in this thread if they bother you.

On 19/12/2017 at 13:14, Galen Gilmore said:

Anybody know what is causing these pacman shaped stars in my images? They always go the same direction, not increasing towards the outside.

Have you made any modifications to your 130PDS at all? If not, this might be the classic "focuser drawtube" problem that we have all faced  There is endless discussion regarding it and ways to "fix" it in this thread.

Is everyone having the same awful awful weather as me - given all the processing of old data going on?

I haven't had my scope out in anger much this year AT ALL so far....

4 hours ago, tony8690 said:

If I had a 130 psd and a eq5 with synscan would I be ab.e to do long exposures? 300 seconds +

 

thanks

t

I have an NEQ6 and with really good polar alignment I could push up to 120-180 s without guiding. I don't think you'll get much better than that without guiding, but with guiding the sky is the limit!

On 25/09/2017 at 17:49, lnlarxg said:

Quick question on this thread regarding the 130pds, with a canon 550d DSLR, are there any focusing issues in achieving prime focus?

I already have a canon t-ring adaptor (baader super low profile one) and a 2" eyepiece to t-thread adapter. 

Reason I ask is having researched SGL and found lots of threads regarding prime focus with Newtonian telescopes not having enough inward (towards the scope) travel on the focuser for DSLRs to achieve prime focus.  I am certainly having this trouble with my 200p dob.

thanks 

This is my setup and you definitely don't have any focus issues. One issue you can face though is that the focus draw tube protrudes a long way into the aperture, which can give your stars a slightly funny shape with a "bite" taken out of them. I performed a relatively simple and reversible (non-destructive) mod to move the primary a little way up the tube and this fixed it for me. This wasn't my idea though, so I take no credit for it - there is a guide on how to do it by one of the other users in this thread a (large) number of pages back. 

TL;DR - Focus will be fine, but it can be improved even further with a small mod!

Had the 130-PDS out last night for my first ever attempt at imaging one target over multiple sessions!!

M45 - it's a classic, and everyone's done it to death, but you've got to try yourself haven't you??

Full details (and a bit more back story) found in the main thread here:

I also managed a quick 1hr on the Double Cluster. Full thread with more details at:

Thanks for looking! Damn, I love this little scope

32 minutes ago, richyrich_one said:

Nice!

As you are dithering you might want to try without darks...some say they can ADD noise.

Oh, and Pixinsight isn't all it's cracked up to be, it's better!

 

14 minutes ago, Adam J said:

I would agree with this. I just dither to remove dust and hot pixels from the image and even out the color noise takes about 16 frames to be effective. I do use a chunk of Bias frames normally about 24, but as I cooled my DSLR to -10c in my M45 at 300s bias is actually the bigger noise component not thermal. 

Thanks for this advice! I dither on literally every frame so I will try a stack without darks and see how it goes..... 

Hey all, two quick images from last night - approx. 1 hour on each. They aren't very good really, need more data, but they could be worse!  Quite pleased with how well the M1 image turned out, given the short focal length of the 130-PDS and the fact I'm using a DSLR. I overcooked M45 a bit but it's not enough data really. Also, just purchased Gradient Xterminator, and I cannot believe it took me so long to fork out for it. It's brilliant when you don't have Pixinsight!

Thanks for looking.

Messier 45 (Pleiades) - Flickr Link

2016-11-07, near Swindon, England

Gear:
* Skywatcher 130-PDS with 0.9x coma corrector (585 mm, f/4.5)
* Skywatcher NEQ6-Pro Synscan
* Canon EOS 550D (unmodified) and Skywatcher 2" LP filter
* ZWO ASI120-MC guide camera
* Skywatcher Startravel 80 guide scope

Acquisition & Processing:
- AstrophotographyTools (APT) and PHD2 guiding with dithering
- 15 x 300s = total 75 minutes @ ISO 800
- 14 flats, library darks (12-14 C), library bias
- Stacked in DeepSkyStacker and post-processed in Photoshop CC 2015 with Gradient Xterminator

Messier 1 (Crab Nebula) - Flickr Link
2016-11-07, near Swindon, England

Gear:
Skywatcher 130-PDS with 0.9x coma corrector (585 mm, f/4.5)
Skywatcher NEQ6-Pro Synscan
Canon EOS 550D (unmodified) and Skywatcher 2" LP filter
ZWO ASI120-MC guide camera
Skywatcher Startravel 80 guide scope

Acquisition & Processing:
- AstrophotographyTools (APT) and PHD2 guiding with dithering
- 11 x 300s = total 55 minutes @ ISO 800
- 14 flats, library darks (12-14 C), library bias
- Stacked in DeepSkyStacker and post-processed in Photoshop CC 2015 with Gradient Xterminator

Hi Carole. Congrats on the fight image, it's nice to have something to look at after all the stress of getting things just right isn't it?

I have seen similar things to the "cloud" when I'm shooting close to a full moon - I think they're stray internal reflections that you would normally never see but the full moon is bright enough to really push them through. I have similar problems with a local street light that stops me being able to image in one direction at all. Perhaps it's time I bit the bullet and tried flocking?

I certainly wouldn't let that worry me until I tried a shot away from the brightness of the moon though. If it's still present in dark sky then further investigation might be necessary!

On 09/10/2016 at 09:31, Squiddy said:

I've read the first and last 10 pages of this thread and must say I'm impressed with this inexpensive little tube. One thing that strike me is that some of you have a camera and mount worth thousends of euro and still choose to use a €200 tube.

I've used a megrez 90 for a while now, but I'd like to try a newtonian tube with a greater aperture and I've been thinking of getting a 150PDS for some time now. So my question to you all are, is the 130PDS better  than the 150PDS, or should I expect pretty much the same result?
The increased weight is no issue as I'm far below the limit of my mount (a Celstron CGE).

Best regards, Kent

One other thing I'd add to this is this: obviously the scope, the camera, and the mount are all important when you are imaging. However you may sometimes hear old imagers say that a good scope on a bad mount will give you bad images but a good mount with a bad scope will still give you reasonable pictures. The mount and the camera are much more expensive to get "right" whereas this little scope is really punching above its weight class. This means if you couple it with some better quality mounts/cameras you can achieve the amazing things the guys in this thread are doing without spending another ££££/€€€€ on optics.

EDIT: Wow, apparently I hit "reply" not realising there were two more pages of discussion! Sorry for the completely out of place comment

EDIT2: Congrats on the new scope, Carole. All this chat about collimation has got me worried mine is off and wanting to get a Cheshire.....

22 minutes ago, Dbswales said:

That's very nice. I can't get to image this favourite of mine due to trees and a 3 storey house that someone rudely decided to build a few years ago. Chainsaw and a couple of gallons of petrol might come in handy. ?

Lovely image and I also appreciate your sub information. Thanks for sharing.

 

Thank you! Yeah, I have three houses that surround my back garden so I had 3 hours to get as much data as I could! There's a street light I have to hide with an umbrella as well because it is about 5 metres from my scope when I'm out there. Far from ideal, but with some perseverance you can get something

My first M31 with the 130-PDS . Well, technically my second, but the first try was plagued with horrors such as dew, clouds, lack of flats, etc. etc.

This is my first image using Gradient Xterminator and I can't believe I have waited this long to try it. With the light pollution near me I have horrid orange gradients across all my images even when I use the LP filter and this has made quite a difference. I will certainly be buying it when the free trial runs out! Thanks for looking

Messier 31 (Andromeda Galaxy) with Messiers 32 and 110
2016-09-11, near Swindon, England

Gear:
Skywatcher 130-PDS with 0.9x coma corrector (585 mm, f/4.5)
Skywatcher NEQ6-Pro Synscan
Canon EOS 550D (unmodified) and Skywatcher 2" LP filter
ZWO ASI120-MC guide camera
Skywatcher Startravel 80 guide scope

Acquisition & Processing:
- AstrophotographyTools (APT) and PHD2 guiding with dithering
- 24 x 300s = total 120 minutes @ ISO 800
- 19 flats, 7 library darks, library bias
- Stacked in DeepSkyStacker and post-processed in Photoshop CC 2015 with Gradient Xterminator

Are any of you 130-PDS imagers going to be at the star party in October? I've not been to one before or met anybody so I'm quite looking forward to it!