#1  
Old 17-10-2020, 01:06 PM
PKay's Avatar
PKay (Peter)
Registered User

PKay is offline
 
Join Date: May 2017
Location: DEPOT BEACH
Posts: 911
M33-First LRGB

Actually quite a few firsts for me.

1: First attempt at M33
2: Dithering between images (I was told that it helps).
3: 2X2 binning on LRGB channels (got to try these things).
4: Processing LRGB in Pixinsight (tedious).
5: Used itelescope (special introductory offer).

Scope used was a Planewave 12.5 CDK located in Spain (no clouds).

Using the remote scope was no different to having it outside the bedroom window :-)

Details are:
20 X 300s Lum
10 X 300s each RBG channel
Total integration 4 hours.

No idea why some of the stars look like doughnuts.

A lot of stuffing around but it was all fun!

PM me if you want some data to play with.


Thanks for looking.
Attached Thumbnails
Click for full-size image (M33_LRGB_PS_red.jpg)
187.3 KB85 views
Reply With Quote
  #2  
Old 17-10-2020, 01:38 PM
Robert_T's Avatar
Robert_T
Registered User

Robert_T is offline
 
Join Date: Oct 2005
Location: Australia
Posts: 2,678
amazing. I've been wondering what those remote access observatories were like. I have no north horizon as it is so anything past single digit positive declination is off limits... why not image then from Spain :-)

and what an image... I started counting the individual emmission nebula here and gave up. Inspiring!
Reply With Quote
  #3  
Old 18-10-2020, 01:01 PM
PKay's Avatar
PKay (Peter)
Registered User

PKay is offline
 
Join Date: May 2017
Location: DEPOT BEACH
Posts: 911
Thanks Robert.

I have just spent 2 days studying PI tutorials regarding LRGB processing.
A big learning curve.

Have found out how dougnuts are 'made'...
Reply With Quote
  #4  
Old 19-10-2020, 02:39 PM
Startrek (Martin)
Registered User

Startrek is offline
 
Join Date: Dec 2017
Location: Sydney
Posts: 2,752
Peter,
Interesting concept , processing a remote image

Good for Cloudy nights

I just saw your comment regarding "Dithering" and was quite surprised you may not have used this procedure in AP before ?
There's an old saying in AP "Dither or Die" but I don't really subscribe to that saying as many folk don't dither and still produce great images. However I can say that my dithered images are much cleaner than un dithered.Its more apparent with noisy images

Your probably aware of the reasons for dithering -
Removes Hot Pixels
Removes Fixed Pattern Noise
Reduces Dark Current ( Noise )
Helps eliminate Satellite trails and other anomalies when you Stack
And so on..........
Dithering just moves your whole frame after each sub anywhere from 0.05 to 2.0 pixels depending on your image scale, guiding program and settings in your capture software.



I started dithering after about 6 months into AP with my Canon 600D and BYEOS capture software and have dithered ever since. Some folk mention it adds to much time to your imaging session but for me it just a part of your capture and you dont really take much notice how long it adds
Now using APT with the new 2600MC camera , the dithering command after each sub seems to take less time than the old DSLR and BYEOS , maybe the dither sequence is more sophisticated in APT or my settings are lower but when you scroll through the frames for post analysis , the frame sure do move in al directions


So for me Dithering is a great benefit , costs you nothing but a little bit more time and the results show for themselves


Most capture software programs have a dithering commands which is automatically integrated with your Guiding program , mine being PHD2


Cheers
Martin
Reply With Quote
  #5  
Old 19-10-2020, 04:15 PM
LostInSp_ce's Avatar
LostInSp_ce
Unregistered User

LostInSp_ce is offline
 
Join Date: Mar 2017
Posts: 754
Beautiful work Peter!
Reply With Quote
  #6  
Old 19-10-2020, 07:05 PM
Jackstar
Registered User

Jackstar is offline
 
Join Date: Dec 2017
Location: Huonville Tas
Posts: 67
That's an excellent image Peter.
I must say i have considered the itelescope for myself. I like the idea of imaging some of the Northern hemisphere options without having to go there.

great start.


Jack
Reply With Quote
  #7  
Old 20-10-2020, 06:44 AM
PKay's Avatar
PKay (Peter)
Registered User

PKay is offline
 
Join Date: May 2017
Location: DEPOT BEACH
Posts: 911
Thanks Martin

Constant learning in this game.
I have seen the little check box in SGP to enable dithering, and up to this point ignored it.
Now it will stay ticked.

Thanks LIS

I love making progress, but at times it is painfully slow...

Thanks Jack

Initially, I used itelescope to try out a new scope.
In itself, remote imaging is quite a learning curve.
It can get expensive (after the intro offers), so I will use it frugally.

I have spent a few days re processing the image.

https://www.astrobin.com/full/9q1jiz/0/
Reply With Quote
  #8  
Old 20-10-2020, 10:26 AM
jahnpahwa (JP)
Registered User

jahnpahwa is offline
 
Join Date: Apr 2020
Location: Canberra, AUS
Posts: 417
Peter, thats really nice! The rework on astrobin is looking really lovely, the extra work you're putting into it is no doubt having an impact.

Can you share what made the donuts appear in pixinsight?
Reply With Quote
  #9  
Old 20-10-2020, 11:10 AM
PKay's Avatar
PKay (Peter)
Registered User

PKay is offline
 
Join Date: May 2017
Location: DEPOT BEACH
Posts: 911
Thanks JP

It pays to take note of each process and save a copy after each so you can 'retreat'.

I had to backtrack all the way to step 2 which was noise reduction.

Step 1: DBE Dynamic Background Extraction. All good.

Step 2: MLT Multi Linear Transform (noise reduction).
The artefact (doughnut) was introduced here and was very subtle (I didn't notice).

Step 3: HT Histogram Transform (now non linear).
Stretching the image made the artefact worse.

Then you go onto curves, deconvolution etc etc and the artefact gets worse again.

To find suitable settings for the MLT process (and there are hundreds), I used a small preview and zoomed in.
I could make big donuts, small donuts, donuts with rings, chocolate donuts...

And then SAVE THE PROCESS that works!
Reply With Quote
  #10  
Old 20-10-2020, 11:11 AM
LostInSp_ce's Avatar
LostInSp_ce
Unregistered User

LostInSp_ce is offline
 
Join Date: Mar 2017
Posts: 754
Quote:
Originally Posted by PKay View Post
I have spent a few days re processing the image.
https://www.astrobin.com/full/9q1jiz/0/
And it shows. You've revealed more dust around the core, which really brings it to life. Time to go shopping for a nice frame to put it in. Well done again!
Reply With Quote
  #11  
Old 20-10-2020, 04:48 PM
etill (Elliot)
Registered User

etill is offline
 
Join Date: Oct 2019
Location: Melbourne
Posts: 82
I was looking at some of the remote observatory options too, not so much because i dont want to sit in my own backyard getting annoyed with my own setup, but they do offer views of the northern hemisphere. Also some offer sample data you can download to try out, which was pretty fun to process.

That's a nice set of data so far, and it definately seems like its worth it to get a view of other parts of the sky, and avoid the weather / clouds down here.
Reply With Quote
  #12  
Old 21-10-2020, 08:28 AM
PKay's Avatar
PKay (Peter)
Registered User

PKay is offline
 
Join Date: May 2017
Location: DEPOT BEACH
Posts: 911
Thanks LIS

Encouragement always well received!

Hi Elliot

itelescope have an introductory offer that you get about 4 hrs of imaging time for $20 AUS.
They give you a 'promo code' that gives you triple points.
Also if a big cloud happens to sit over the observatory, or you stuff up the program, you get a refund.
Not to mention rubbing shoulders with professional astronomers :-)
Reply With Quote
  #13  
Old 23-10-2020, 07:23 PM
Hotpies (Brad)
Registered User

Hotpies is offline
 
Join Date: Jan 2020
Location: Melbourne
Posts: 2
Quote:
Originally Posted by PKay View Post
Thanks LIS

Encouragement always well received!

Hi Elliot

itelescope have an introductory offer that you get about 4 hrs of imaging time for $20 AUS.
They give you a 'promo code' that gives you triple points.
Also if a big cloud happens to sit over the observatory, or you stuff up the program, you get a refund.
Not to mention rubbing shoulders with professional astronomers :-)

Hi Peter,


This image is STUNNING!! Well done.


This remote imaging has got me intrigued. I was looking at the website, so when you sign up, you get 40 "Free" points you can access once you buy a subscription. The the starter pack is 20 points. With the triple points, you would have a total of 100 points.


Is this enough for a 4 hour image? It looks like most the scopes are like 80 or 100 points for an hour?



Certainly looks like something that could be super fun, especially to image targets which are not available to us.


Again, well done on the beautiful image especially the updated one on Astrobin!



All the best,
Brad.
Reply With Quote
  #14  
Old 24-10-2020, 08:51 AM
PKay's Avatar
PKay (Peter)
Registered User

PKay is offline
 
Join Date: May 2017
Location: DEPOT BEACH
Posts: 911
Hi Brad

Welcome to the forum and thanks for the praise!

With regards to itelescope, it is a bit confusing.
The 'starter plan' will give you 4 hours for 100 points.
Well, at least it did for me :-)
Reply With Quote
  #15  
Old 24-10-2020, 12:14 PM
Hotpies (Brad)
Registered User

Hotpies is offline
 
Join Date: Jan 2020
Location: Melbourne
Posts: 2
Your welcome.



Been a long time lurker of the forum, that's for sure. The content on here is mind blowing. Would love to try and get a little more involved once I know what I'm doing


Ill give the site a try for a bit of fun and experimentation and see how we go.


Look forward to seeing more amazing pictures from you
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 09:50 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
Limpet Controller
Advertisement
NexDome Observatories
Advertisement
Testar
Advertisement
Astronomy and Electronics Centre
Advertisement