From: Milton Aupperle <milton@outcastsoft.com>

Date: July 24, 2009 4:05:49 PM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] Photometry on an asteroid 790 Pretoria


Hi Terrence;


On 24-Jul-09, at 3:30 PM, Terrence Redding wrote:



Thanks.


I have a DSLR reflex with a remote timer that lets me set timed exposures every so many minutes or hours.  


Astro IIDC can do that too. Change the Frame rate and it can record a frames at specific intervals regardless of what the camera is capturing at. We also have Apple Scripts available that can control Astro IIDC frame or movie capture too at any time interval you want.


So I could use that to gather a series of images and then use Astro_IIDC to process - is that right?


Yes for individual frames directly into the "Process Image..." where you can enhance the images and also do Photometric and Astrometric measurements.


For stacking or batch photometry, you need to convert the frames into a 16 bit RGB 48 movie using the "Images to RGB48 Movie.." menu item (page 45 of the Manual) under the "Processing" menu. Then you can stack and align them once it's a movie.


If your going to do this with a DSLR, make sure you do not capture frames as JPEG and they should TIFF. And for Color images, your not going to get accurate photometric results. The bayer filter on the CCD cameras more or less prevents that from being accurate.


HTH..


Milton J. Aupperle