From: albe albo <richter1956@yahoo.com>
Date: December 19, 2008 2:44:06 AM MST
To: Astro_IIDC@yahoogroups.com
Subject: Re: [Astro_IIDC] New file uploaded to Astro_IIDC-Puzzling Problem
I suspect something about air "blades" flowing almost parallels each other, making a kind of regular shifting (like the refractions caused by a pile of different moving glasses ).
Now that i understood them i'm very happy that i could recover many of the affected images.
Milton would you send to me for an experiment a sample of your double image? (with no deconvolution is better)?
I'd like to try the treatment in order to check if it is the same kind of problem and if they may be recovered too.
Who knows...you could add a new function to AIIDC (LOL) setting directly the doubling correction in a transparent way for the final user (he/she won't know what the software is doing so he/she won't use photoshop).
TTYL
Alberto
From: Milton Aupperle <milton@outcastsoft.com>
To: Astro_IIDC@yahoogroups.com
Sent: Friday, December 19, 2008 4:28:07 AM
Subject: Re: [Astro_IIDC] New file uploaded to Astro_IIDC-Puzzling Problem
Hi Alberto;
I've seen this before. In my neck of the woods living under the jet stream, I have many movies where I have frames with seemingly two (or more) sharp images offset in any direction up to 30 pixels / arc seconds , depending on the predominant turbulence flow direction.
I don't know how to explain it from a meteorological perspective, but it's not uncommon here in Western Canada.
HTH..
Milton Aupperle
On 18-Dec-08, at 5:40 PM, albe albo wrote:
Thank you Milton and Alan.
You both know that i'm trying and trying to find alternate or complementary way for aligning/processing .
I applied de-warping to those mosaic images but when I did the first version of Copernicus something was strangely wrong and i didn't understand WHAT.
My eyes were puzzled by something unusual.
Since i'm pushing the focal to high values i'm noticing a strange blurring that it is not possible to improve with normal convolutions.
After exhamining carefully the images i noticed that the more contrasted features seemd to be doubled approx 5-6 pixels far from their originals.
I guessed that there was a "ghost" image that "directionally" messed up the overall sharpness even if the image itself is not clearly visible.
So i did an attempt duplicating the layer and subtracting a properly shifted layer (properly means experimenting the best position) set to 20% transparency on a black background layer et ..voilà i had the confirmation of the 2nd image exhistance!
Please check the attached images (zip file).
I suggest to select the images and open them at once in preview so you may perform a quick toggle between them.
The image numbered 1 is the original one the images numbered 2 are NOT sharpened or processed but the only process i did was the ghost subtraction, nothing else.
This mean that there was a single precise ghost messing up the sharpness.
The white arrows shows (on the images N.1) the whiter rims external to the craters that puzzled me.
I have this problem both with C8 and LX10 OTAS.
It is NOT due to processing (alignment, stacking or deconvolution) .
The ghost is present in the movies too and appears as a quick shift of the feature due to the seeing but i'm wondering: why that quick shift moves straight and directionally?
Usually the seeing should move random generating a circle of confusion... not a ghost shifted image.
Maybe a partial deflection due to the red /ir filter into a not perfectly aligned optical path?
The OTA is pretty well collimated (the resolution of the details confirms that)
Now i will check again all my mosaics including The 4 rimae.
The improvement is very noticeable and i'm happy that i can recover some images that i considered as lost.
Someone knows why the ghosts do exist?
Maybe they are poltergeist craters?
Cheers!
Alberto
From: Alan Friedman <alan@greatarrow. com>
To: Astro_IIDC@yahoogro ups.com
Sent: Thursday, December 18, 2008 10:52:10 PM
Subject: Re: [Astro_IIDC] New file uploaded to Astro_IIDC
Thanks for pointing out Alberto's post - I missed it first time around. That is an excellent image and the wide field adds much interest beyond the famous Copernicus. Great work!
best,
Alan
On Dec 18, 2008, at 4:43 PM, Milton Aupperle wrote:
Very stunning Copernicus and area, Alberto. Even though I'm on dial-
up at 2600 baud, it was well worth the 40+ second download time.
I really like the view around the "Domezilla" area to the west and
north. The ash deposits around it are really nicely defined (striped
area).
Thanks for sharing..
Milton Aupperle
(PS - it was -32° centigrade here last night and unlikely to get
above -25°C at night for the rest of the week).
On 18-Dec-08, at 10:24 AM, Astro_IIDC@yahoogro ups.com wrote:
>
> Hello,
>
> This email message is a notification to let you know that
> a file has been uploaded to the Files area of the Astro_IIDC
> group.
>
> File : /Lunar/081208- Copernicus- Region-V4. jpg
> Uploaded by : richter1956 <richter1956@ yahoo.com>
> Description : Copernicus, Eratosthenes & Friends...
>
> You can access this file at the URL:
> http://groups. yahoo.com/ group/Astro_ IIDC/files/ Lunar/081208-
> Copernicus-Region- V4.jpg
>
>
<comparison.zip>