From: Ray Byrne <ray@in4media.co.uk>
Date: February 6, 2009 3:18:00 PM MST
To: Astro_IIDC@yahoogroups.com
Subject: Re: [Astro_IIDC] First Lunar Image with Grasshopper Mono Camera
Hi Milton,
That is one fine image of a waxing Moon. I'd like to see the full-size version.
On 6 Feb 2009, at 20:56, Milton Aupperle wrote:
Hi Folks;
I took my first lunar images with the GrassHopper Camera on Feb 4th. I
have only been using it for DSO imaging prior to this.
This is a reduced to half size of the original composite:
http://groups.yahoo.com/group/Astro_IIDC/files/Lunar/Luna_20090204_MJA.jpg
Seeing was poor with fast "boiling" turbulence jumping +/- 10 arc
seconds, erratic thicknesses of clouds and light wind, shooting with
the C8 at 2,000 mm focal length. I used a red (Wratten 23A) filter on
the 1384 x 1036 mono camera in 16 bit mode and recorded about 350 to
400 frames per movie (total of 16 gigabytes of video recorded).
I used 22 to 32 MAP Selection areas for each of the nine movies
resulting Stacked image to test out the new alignment code in Astro
IIDC 4.02.00 beta (not yet available).
I also had to use the "Adjust pixel area brightness if frame
brightness changes." stacking option too, because the passing clouds
changed the brightness enough that pixel matching would fail. You can
use this IF (AND ONLY IF) your tracking is very very good, because if
the moon drifts across the FOV, that changes the overall brightness
and then brightness adjustment is making corrections that are not
cloud dependent.
TTYL..
Milton Aupperle
ATB
Ray Byrne
in4media | graphic and website DESIGN
T: 01793 435704
