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JeanB
Pooh-Bah


Reged: 07/11/11

Loc: Montreal, Canada
Flats and solar mosaic: what a difference! new
      #6046906 - 08/26/13 12:21 PM

Hi everyone,

assembling a whole disk mosaic had been a headache. Daniel Borcard from Astro Quebec suggested to use flats in Registax to overcome the problem associated with the smaller prism B600 in my Lunt LS60. It made quite an improvement!

I know, this 15 august solar disk is outdated but I did not want to post it before, due to its complete lack of quality.

Here it is now thanks to flats.

https://dl.dropboxusercontent.com/u/78493639/MozaicColor.jpg

Jean


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Peter Z
super member


Reged: 05/03/10

Loc: Winnipeg, MB, Canada
Re: Flats and solar mosaic: what a difference! [Re: JeanB]
      #6047062 - 08/26/13 02:07 PM

Hi Jean.


That's a beauty! Do you have a "Before" shot to compare with this fine "After" shot?

Cheers.
Peter.


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JeanB
Pooh-Bah


Reged: 07/11/11

Loc: Montreal, Canada
Re: Flats and solar mosaic: what a difference! new [Re: Peter Z]
      #6047098 - 08/26/13 02:24 PM

Here is the «before»...

https://dl.dropboxusercontent.com/u/78493639/MOZ2ab%20copy.jpg

the transition between the four panels was almost impossible to get rid of...

Regards

Jean


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R Botero
Pooh-Bah


Reged: 01/02/09

Loc: Kent, England
Re: Flats and solar mosaic: what a difference! new [Re: JeanB]
      #6047155 - 08/26/13 02:54 PM

Great result Jean! Well done.

Roberto


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Andy Devey
Carpal Tunnel


Reged: 05/06/11

Re: Flats and solar mosaic: what a difference! new [Re: R Botero]
      #6047251 - 08/26/13 03:56 PM

Excellent work Jran and a great comparison, I am going to have to try those flats

Regards

Andy


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ASTROTRUCK
sage


Reged: 01/02/10

Re: Flats and solar mosaic: what a difference! new [Re: Andy Devey]
      #6047528 - 08/26/13 06:54 PM

how were the flats used - what were the stages ?
some use the program imerge with settings (from posts by members) 256,25,0 with no merge lines - without flats.

thanks


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Paul Hyndman
sage


Reged: 07/13/04

Loc: Connecticut Shoreline USA
Re: Flats and solar mosaic: what a difference! new [Re: ASTROTRUCK]
      #6047543 - 08/26/13 07:13 PM

Wow Jean, that's gorgeous!!!

Thanks for sharing.

Paul


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BKMaynard
super member
*****

Reged: 02/21/13

Loc: Cahokia, Il. (st.louis area)
Re: Flats and solar mosaic: what a difference! new [Re: Paul Hyndman]
      #6048077 - 08/27/13 01:08 AM

I never had any good results,with flats using Registax What's the trick?

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steveward53
Pooh-Bah


Reged: 05/14/12

Loc: Newmarket,UK
Re: Flats and solar mosaic: what a difference! new [Re: BKMaynard]
      #6048133 - 08/27/13 02:18 AM

Certainly irons out the wrinkles ...

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LarryAlvarez
Post Laureate
*****

Reged: 08/12/05

Loc: Texas
Re: Flats and solar mosaic: what a difference! new [Re: steveward53]
      #6048205 - 08/27/13 04:43 AM

Remarkably better than the before.

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JeanB
Pooh-Bah


Reged: 07/11/11

Loc: Montreal, Canada
Re: Flats and solar mosaic: what a difference! new [Re: BKMaynard]
      #6048479 - 08/27/13 09:50 AM

Quote:

I never had any good results,with flats using Registax What's the trick?




I choose a section of the sun with a minimum of features. I adjust the focus and do not touch it during the process.

I attach a white plastic bag in front on the telescope.

https://dl.dropboxusercontent.com/u/78493639/Flats.jpg

Using IC Capture I and the DMK camera I make sure the field is filled with the sun.

I then adjust the histogram of IC capture to have it in the middle (average grey).

https://dl.dropboxusercontent.com/u/78493639/IC%20Capture.jpg

I then shoot approx 500 AVI frames (named flats)

I continue my shooting session of the sun (without the bag of course).

In registax you have to open first the AVI flats and process as usual. No wavelettes. Save as bmp file (Flats)

You then load the bmp file as a flat in Registax. All your AVI files will then be automatically processed with this flat.

https://dl.dropboxusercontent.com/u/78493639/RegistaxF.jpg

Et voilą! The rest is assembling the panels in PS which I do manually.

Hope this will help.

Jean


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astrovale
Carpal Tunnel
*****

Reged: 02/19/06

Loc: Rimini, Italy
Re: Flats and solar mosaic: what a difference! new [Re: JeanB]
      #6048525 - 08/27/13 10:17 AM

Wow Jean! What a great improvement! I think you should be very happy with this mosaic and of your newly acquired technique!

Well done!

Luca


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JeanB
Pooh-Bah


Reged: 07/11/11

Loc: Montreal, Canada
Re: Flats and solar mosaic: what a difference! new [Re: ASTROTRUCK]
      #6048652 - 08/27/13 11:41 AM

Quote:

how were the flats used - what were the stages ?
some use the program imerge with settings (from posts by members) 256,25,0 with no merge lines - without flats.

thanks




Just tried the imerge program with the settings you mentioned. Terrific program indeed! But when used on my files without flats it won't perform very well. However, with my flat-processed files it seems superior to photoshop CS2 for merging.

So thank for the imerge tip!

Jean


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rigel123
Postmaster
*****

Reged: 06/29/09

Loc: SW Ohio
Re: Flats and solar mosaic: what a difference! new [Re: JeanB]
      #6048804 - 08/27/13 01:07 PM

That is quite an improvement Jean! I haven't tried flats before, I may have to check that out!

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BYoesle
Post Laureate
*****

Reged: 06/12/04

Loc: Goldendale, Washington USA
Re: Flats and solar mosaic: what a difference! new [Re: rigel123]
      #6048887 - 08/27/13 01:46 PM

Fantastic mosaic Jean!

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JeanB
Pooh-Bah


Reged: 07/11/11

Loc: Montreal, Canada
Re: Flats and solar mosaic: what a difference! new [Re: BYoesle]
      #6049167 - 08/27/13 04:08 PM

Thanks you very much everyone!

Jean


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BKMaynard
super member
*****

Reged: 02/21/13

Loc: Cahokia, Il. (st.louis area)
Re: Flats and solar mosaic: what a difference! new [Re: JeanB]
      #6049767 - 08/27/13 10:05 PM

most helpful indeed!

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ASTROTRUCK
sage


Reged: 01/02/10

Re: Flats and solar mosaic: what a difference! new [Re: JeanB]
      #6053378 - 08/29/13 09:17 PM

LONG POST - A FEW QUESTIONS

1)focus issue - out of focus to give a full field corner to corner of the disk out of focus to ensure no features ?? therefore making a flat @ 900mm giving a narrower field filling corner to corner with a flat bright even brightness corner to corner.

2)my scope is 100mm f9 - will use it as 900 but also 450 with reducer - do i then use the same flat in regi for an image @ 900 & full disk also at 500 ?? - read elsewhere cant change orientation of scope unless take new flat for processing with flats for each orientation.
apparently the corners need to line up when processing ?

3)in regi - the flat - is it after also converting it to a single image or as an avi flat ?

4)can i use a white garbage bag or must the plastic be partially transparent - is white bag too opaque ?

5) can i save the 1 flat to use in regi for all images both close up or full disk for all future sessions ?
again they seem to state need flat for every orientation of scope for different focal lengths & even if i only move tube if i close down then reopen for additional imaging.

no-one around here uses flats so cant see it in actual usage.
some of my images are not even across the field due to coronado sweet spot resulting from front etelon - edge darkening is ok but central brightening is not.

thanks for responses anyone .


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raylal
Carpal Tunnel


Reged: 04/19/10

Loc: Cornwall, Ont., Canada
Re: Flats and solar mosaic: what a difference! new [Re: ASTROTRUCK]
      #6053916 - 08/30/13 07:35 AM

Wonderful and very helpful presentation Jean, well documented. Congratulations on the gorgeous results.
Well done !!!! and thank you.

Ray


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JeanB
Pooh-Bah


Reged: 07/11/11

Loc: Montreal, Canada
Re: Flats and solar mosaic: what a difference! new [Re: raylal]
      #6054096 - 08/30/13 10:07 AM

Hello ASTROTRUCK,

I am sure no expert on this but I will try to answer your question as best as I can, leaving other to correct me;

1)focus issue - out of focus to give a full field corner to corner of the disk out of focus to ensure no features ?? therefore making a flat @ 900mm giving a narrower field filling corner to corner with a flat bright even brightness corner to corner.

A: The focus has to be the same for the flats and for imaging. My understanding is that if you are out of focus for flats it will also displace the area you want to correct even in the corners.

2)my scope is 100mm f9 - will use it as 900 but also 450 with reducer - do i then use the same flat in regi for an image @ 900 & full disk also at 500 ?? - read elsewhere cant change orientation of scope unless take new flat for processing with flats for each orientation.
apparently the corners need to line up when processing ?

A: I haven't try flats yet for a different magnification.

3)in regi - the flat - is it after also converting it to a single image or as an avi flat ?

A: you first process avi flat in REgistax and convert the result as a bmp file. It is this file that you have to load before processing your solar avi. Registax will automatically use it.

4)can i use a white garbage bag or must the plastic be partially transparent - is white bag too opaque ?

A: I used a white garbage bag. It has to let sufficient light go through for your capture software to «see» it.

5) can i save the 1 flat to use in regi for all images both close up or full disk for all future sessions ?
again they seem to state need flat for every orientation of scope for different focal lengths & even if i only move tube if i close down then reopen for additional imaging.

A: I used the same flat for two different sessions but only for full disk. I worked nicely but it may have been a coincidence.

Hope this will help.

Jean


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