#1  
Old 09-03-2013, 08:31 AM
Lee's Avatar
Lee
Colour is over-rated

Lee is offline
 
Join Date: Sep 2005
Location: Newcastle, Australia
Posts: 2,414
Plate solving for dummies??

After a fruitless search for a faint fuzzie, I realise I'm in need of a plate solving application....

From a lot of searching online, there seems to be a bunch of options, all seeming quite confusing as to exactly what is needed, and how it works....

What I'd like is to be able to take an image of sky, and have the application tell me the centre of the image (which from what I can tell is the minimum of a plate solve?)....
Of course a bonus would be a link to my G-11 Gemini (L1).....

Can anyone suggest a solution to my needs?
I don't mind paying, but don't feel I need the all singing all dancing MaximDL?? I've asked to join the Elbrus Yahoo Group, but haven't heard back yet....

Is MaxPoint what I'm after??
I use nebulosity for imaging at present, with a Meade DSI Pro II (an Atik 420 on the way..), from what I've read, the Atik Capture software can link to MaximDL +/- MaxPoint??
Reply With Quote
  #2  
Old 09-03-2013, 11:17 AM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,481
The application that you are after is Elbrus which is free and used within sequence generator pro which you can get a 45 day free trial. It does exactly what you want and much much more. See this site for more information and videos. http://www.mainsequencesoftware.com/
Hope this helps
Reply With Quote
  #3  
Old 09-03-2013, 12:24 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 18,140
Another freebee is UNIMAP.
Reply With Quote
  #4  
Old 09-03-2013, 01:31 PM
Octane's Avatar
Octane (Humayun)
IIS Member #671

Octane is offline
 
Join Date: Dec 2005
Location: Canberra
Posts: 11,158
MaximDL with PinPoint LE has been a great success for me.

H
Reply With Quote
  #5  
Old 09-03-2013, 02:28 PM
Terry B's Avatar
Terry B
Country living & viewing

Terry B is offline
 
Join Date: Mar 2006
Location: Armidale
Posts: 2,759
I use elbrus as well. It talks to ascom very easily. Not sura about G11 but I'm sure someone will know.
The database files are here
http://atlante.org.es/catalogos/elbrus/
You need to download all of it and extract it into a folder..

more info here
http://astrosurf.com/pulgar/elbrus/elbrusin.htm

I'm not sure why the elbrus group hasn't contacted you yet but there hasn't been any activity for over a week.
I can send you the latest exe files if you like. The zip file is only 512k but this makes it slightly too big for me to attach here. Send me your email and I can send it to you.
Cheers

Terry
Reply With Quote
  #6  
Old 09-03-2013, 04:11 PM
swannies1983 (Dan)
Registered User

swannies1983 is offline
 
Join Date: May 2006
Location: Adelaide
Posts: 781
Lee, I was in the exact same position as you. I have been imaging with a RC8 on an EQ6. The problem is that my mount isn't GoTo compatible. I currently use settings circles but I wanted a more accurate way to find faint fuzzies. Plate solving was the way to go.

After doing some reading, I downloaded Astrotortilla http://sourceforge.net/p/astrotortilla/home/Home/ and it does exactly what I need.

You need to download star catalogues, which is what AstroTortilla will look through to match star patterns when it comes to plate solving. The amount of catalogues you need will depend on your image scale. The smaller the scale, the more catalogues (larger download required). See the manual on the home page to guide you.

When you install AstroTortilla, it will ask you which index files (star maps) to download. It's generally pretty slow but you can download index files directly from here. For my image scale, I had to download 4004, 4005, 4006, 4007, 4008 and 4009 series. Each series covers the entire sky. However, 4008-4019 has only one file to download and each covers the full sky. 4005-4007 are made up of 12 tiles (see the hp.png in this directory to show you what regions of the sky each tile covers). Series 4000-4004 are made up of 48 tiles (see the hp2.png in this directory to show you what regions of the sky each tile covers). So, you can reduce your download by only getting the tiles that cover what is visible in your sky. Let me know if this is confusing!

So once it's all installed, this is my workflow:

  1. Polar align
  2. "Sync" my setting circles to a star
  3. Look up object of interest
  4. Move scope and match setting circles RA and DEC based on RA and DEC of object
  5. Connect camera
  6. Take a 5 sec shot at ISO1600 (only need a 5 sec shot). I use jpeg files.
  7. Go into AstroTortilla and connect to my mount via ASCOM*
  8. Click Tools and then GoTo Image. This allows me to load my 5 sec image.
  9. It should start to plate solve. It generally takes 30-60secs but can take up to 2 mins depending on how many index files it needs to solve. Once solved, I move the mount in RA and DEC and plate solve again until I'm happy the object of interest is centred.
A few things that will affect solving time:


  1. Scale Minimum and Scale Maximum. I generally set this to +/- 10% of my maximum image scale (based on the longest dimension of my sensor)
  2. Sigma. This is how many objects it detects. When it starts plate solving, it should give a number of how many objects it detects. Aim for about 20-200. Anymore, and it will take a long time to plate solve. Any less, and it may not solve at all. Increasing the sigma, reduces the number of objects identified.
*You can use AstroTortilla to move you mount after plate solving to the correct RA and DEC. My ASCOM driver is old (no updates since 2006) and it doesn't really work so I just manually move the mount, plate solve, move the mount, plate solve etc until I'm happy.


I hope this helps!


Dan
Reply With Quote
  #7  
Old 10-03-2013, 08:27 AM
Lee's Avatar
Lee
Colour is over-rated

Lee is offline
 
Join Date: Sep 2005
Location: Newcastle, Australia
Posts: 2,414
Thanks everyone for your detailed replies.... Will give these options a try....
as a test last night I slewed to M83, and took a frame, uploaded to http://nova.astrometry.net/ .... to my delight, it reported M83 was actually near frame centre.... the old Gemini is pointing better than I thought!

M83 -- RA 13h 37m 00.9s; DEC -29deg 51' 57"

centre of my frame reported as - 13h 48.711s; DEC -29deg 56' 23"

only missed by several minutes.....



Reply With Quote
  #8  
Old 10-03-2013, 08:36 AM
swannies1983 (Dan)
Registered User

swannies1983 is offline
 
Join Date: May 2006
Location: Adelaide
Posts: 781
Astrotortilla uses the Astrometry.net engine. But you don't have to wait for someone to solve it for you . How long did it take for your image to get solved?
Reply With Quote
  #9  
Old 10-03-2013, 10:35 AM
Lee's Avatar
Lee
Colour is over-rated

Lee is offline
 
Join Date: Sep 2005
Location: Newcastle, Australia
Posts: 2,414
Took about 30s to solve I'd say.... that was just uploading a fit file, anf giving it no further info....

Seems faster if you give it some limits, like a RA/Dec radius, or approx image scale....
I experimented by cropping little squares of random star fields from some jpg images I'd done, and just tell the engine the field is say 0.01 deg to 1 deg, seems to take 10s or so for a solution....

I'm still going to get a self-contained solution going, but astrometry.net is very cool.... I'm continually amazed by what we have free access to, and the high prices we need to pay for other stuff!

If anything - it seems an easy way to get a precise arcsec/pixel measurement, just upload an image you've taken with whatever OTA/CCD, and it will tell you....
Reply With Quote
  #10  
Old 10-03-2013, 10:38 AM
alistairsam's Avatar
alistairsam
Registered User

alistairsam is offline
 
Join Date: Nov 2009
Location: Box Hill North, Vic
Posts: 1,815
Maxim and pinpoint works great from me, the useful bit is when your object is slightly off centre, you right click and choose centre here it slews and centers the object.
Else Elbrus should work on its own, or its great with SGP.

I think it'll be more useful if you use it with a scope control software as then it can auto correct and centre after the plate solve. Saves so much of effort with manual centering if you just had plate solve.
Reply With Quote
  #11  
Old 10-03-2013, 10:54 AM
Octane's Avatar
Octane (Humayun)
IIS Member #671

Octane is offline
 
Join Date: Dec 2005
Location: Canberra
Posts: 11,158
The other advantage of MaximDL with Pinpoint is that it solves the image after you take it, and stores the RA/DEC coordinates in the FITS header.

Why is this important? Because when it come to stacking, you can use the astrometric method of stacking which is the most precise of all the methods.

H
Reply With Quote
  #12  
Old 10-03-2013, 05:23 PM
Terry B's Avatar
Terry B
Country living & viewing

Terry B is offline
 
Join Date: Mar 2006
Location: Armidale
Posts: 2,759
Quote:
Originally Posted by Octane View Post
The other advantage of MaximDL with Pinpoint is that it solves the image after you take it, and stores the RA/DEC coordinates in the FITS header.

Why is this important? Because when it come to stacking, you can use the astrometric method of stacking which is the most precise of all the methods.

H
Elbrus also does this.
Reply With Quote
  #13  
Old 11-03-2013, 12:55 PM
Octane's Avatar
Octane (Humayun)
IIS Member #671

Octane is offline
 
Join Date: Dec 2005
Location: Canberra
Posts: 11,158
Good to know. Thanks, Terry!

H
Reply With Quote
  #14  
Old 13-03-2013, 08:30 AM
Lee's Avatar
Lee
Colour is over-rated

Lee is offline
 
Join Date: Sep 2005
Location: Newcastle, Australia
Posts: 2,414
Quote:
Originally Posted by allan gould View Post
The application that you are after is Elbrus which is free and used within sequence generator pro which you can get a 45 day free trial. It does exactly what you want and much much more. See this site for more information and videos. http://www.mainsequencesoftware.com/
Hope this helps
Have had a look, asked a few questions - SG Pro/Elbrus looks like what I'm after for sure, thanks..... $100 seems cheap at twice the price!
Reply With Quote
  #15  
Old 13-03-2013, 05:57 PM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,481
Quote:
Originally Posted by Lee View Post
Have had a look, asked a few questions - SG Pro/Elbrus looks like what I'm after for sure, thanks..... $100 seems cheap at twice the price!

Lee, you will not regret it. The main thing to get right is the arc sec per pixel for your camera and scope. Ccdcalc gives an accurate guide to this. Once an image is solved just use 2x2 any angle and the Arcseconds per pixel that you have determined and it will always work as long as your RA and dec are reasonably close to your target.
The yahoo group will respond almost immediately to any queries. There is so much more to the program but I'm sure you realize this as there are quite a few of us now using this program exclusively.
Allan
Reply With Quote
  #16  
Old 13-03-2013, 06:49 PM
Lee's Avatar
Lee
Colour is over-rated

Lee is offline
 
Join Date: Sep 2005
Location: Newcastle, Australia
Posts: 2,414
Even easier I think - I just take a frame, and get nova.astrometry.net to plate solve it, they tell you your exact arcsec/pixel and angle..... I won't be able to play with it yet, am waiting for my Atik 420 to arrive, SG Pro won't drive the old Meade DSI I'm using.....
Reply With Quote
  #17  
Old 13-03-2013, 06:56 PM
Octane's Avatar
Octane (Humayun)
IIS Member #671

Octane is offline
 
Join Date: Dec 2005
Location: Canberra
Posts: 11,158
Can SequenceGenerator Pro handle the STL with its built-in guide camera?

H
Reply With Quote
  #18  
Old 13-03-2013, 07:23 PM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,481
H to be honest I don't fully know but if it's ASCOM controlled then I assume both can. Send a question to yahoo groups at http://tech.groups.yahoo.com/group/m...uencesoftware/
In the home page it says it supports sbig cameras. There is a 45 day free trial with no restrictions, so have a go.
Allan
Reply With Quote
  #19  
Old 21-03-2013, 09:18 AM
Lee's Avatar
Lee
Colour is over-rated

Lee is offline
 
Join Date: Sep 2005
Location: Newcastle, Australia
Posts: 2,414
Thumbs up Sequence generator Pro rules

I'm impressed - fired up sequence generator Pro/elbrus last night....

Turned on the Gemini, cold started, no model.
Typed in the RA/Dec for M83, automatically slewed, plate solved, correction slew, solved - bang, on target.... did this for several other fuzzies just for laughs....
No more craning my head into eyepieces dangling off my GEM trying to build a reasonable pointing model! Now I just need more aperture....
Reply With Quote
  #20  
Old 21-03-2013, 09:33 AM
Terry B's Avatar
Terry B
Country living & viewing

Terry B is offline
 
Join Date: Mar 2006
Location: Armidale
Posts: 2,759
Quote:
Originally Posted by Lee View Post
I'm impressed - fired up sequence generator Pro/elbrus last night....

Turned on the Gemini, cold started, no model.
Typed in the RA/Dec for M83, automatically slewed, plate solved, correction slew, solved - bang, on target.... did this for several other fuzzies just for laughs....
No more craning my head into eyepieces dangling off my GEM trying to build a reasonable pointing model! Now I just need more aperture....
Well done.
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 03:41 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Advertisement
NexDome Observatories
Advertisement
OzScopes Authorised Dealer
Advertisement
Lunatico Astronomical
Advertisement
SkyWatcher Australia
Advertisement
Bintel
Advertisement
Celestron Australia
Advertisement
Meade Australia
Advertisement
Astronomy and Electronics Centre
Advertisement