From: Milton Aupperle <milton@outcastsoft.com>

Date: March 27, 2012 12:09:01 PM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] Venus True/False


Hi Alan;


Thanks for the details.


That is quite a noisy image, but with a bit of processing, you can see all the features you show in your stacked image.


Are you shooting in 8 bit or 16 bit? 16 will give better gradations.


Since Venus doesn't have fine (< 2 pixel width) details, you might want to experiment using Mono 2x2 binning, which will give you roughly 4 times increase in brightness. So you could reduce the Brightness (Gain) and / or increase the frame rate too.


Also the software binning does not reduce image size, so the image scale remains the same.


HTH..


Milton Aupperle


On 27-Mar-12, at 11:36 AM, Alan Friedman wrote:




Thanks Milton,


The bright regions represent the highest albedo in the cloud tops... though beyond this I don't know. I did find that the cloud rotation is quite fast... obvious movement is seen in 30 minutes. As you've guessed, the data is shot at high gain and is quite noisy. One has to take as many frames as possible in a short time span. I used both 33ms and 66ms shutter settings. 33 required maximum brightness and the frames were still quite dim. 66 could be used with the brightness slider setting down to 640, though the resulting frames were softer. Here is a single frame from one of the 33ms streams:


http://www.avertedimagination.com/images/33_1.jpg


best,

Alan


On Mar 27, 2012, at 1:19 PM, Milton Aupperle wrote: