From: Milton Aupperle <milton@outcastsoft.com>

Date: May 8, 2009 3:46:38 PM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] definition of images..MAP & otherwise... [3 Attachments]

Mark;

Your using an earlier version of Astro IIDC 4.x too (likely 4.02?), and 4.04.00 is the current version I'd recommend.

The stacking log tells most of the story:

Why do you have

"Adjust pixel area brightness if frame brightness changes."

turned on? See page 33 of the manual for a complete explanation of when to use it, as it primarily for DSO's. If your tracking is poor, that will cause all sorts of issues with Lunar images for this setting (it's explained why in the manual).

Thirdly, did your movie only have 108 frames? All your stacking it is 12 frames (in the first case), which frankly is very very few. I shoot usually 800 to  2500 frames and then have it stack 70 to 300 (depending on the target, seeing conditions and gain levels).

Your selection areas are not really good and you tend to pick just big white areas, which have no information to lock onto (white is white). High contrast edges (shadows ) where  there are black / white areas with multiple features are much better choices. Always try and pick areas with multiple things going on, as I'll illustrate below.

Using the same image, here are selection Areas I could have chosen (assuming turbulence isn't too bad). Note that I avoided in most cases just picking white blobby areas or black areas as neither black nor white contain any information:

http://groups.yahoo.com/group/Astro_IIDC/files/Other/MJA_Image_Selection_Area_Picks.jpg

I won't explain each one, but several have good common features:

Area 1 has a good dark edge and there are small craters with white edges in the shadows to make it unique.

Area 2 has a white and black crater edge, but also is on a gray ridge line too.

Area 4 has a very good hard diagonal white / gray edge, and the 4 dark craters make it unique along that edge. Usually I avoid long straight edges unless I am selection one of the end points of it or have other unique features with it too.

Areas 5, 7, 12, 16 and 17 has multiple Black and White crater edges.

Area 9 has multiple white, black and gray tonal features that are unique.

Area 10 is at junction of two craters termini (looks like a anchor), which gives us a good unique feature to lock onto.

Area 11 has a gray "notch" through the big white crater rim and also has those small craters on the gray area. Note that I kept the amount of pure white to minimum.

Area 21 is what I would pick if I was desperate, but it has the white edge and then some white patches surrounded by gray. As long as turbulence is not too excessive, it should be able to match that up fairly well.

HTH..

Milton Aupperle

On 8-May-09, at 10:56 AM, Mark Gaffney wrote:

Hi Milton, I`m getting this for the snapshotted image preview window

after stacking & aligning;