From: Phil Houston <pkh111@knology.net>

Date: June 19, 2006 3:34:01 PM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] Jupiter June 15

Alan,

Thanks.  I am using a  filter set from True Technology containing a clear, Ir block, R,G,and B filter.  I must use the Ir blocking filter in order to get a decent color balance so the Ir filter is used with all other filters.  So far it's been a convenience issue rather than a performance one. Removal would require disassembling the setup. I should try an unfiltered luminance, though.  What do you recommend? 

I enjoyed your comparison between the 6" scope and 10" as it pertains to alignment and stacking.  Using a 2x Barlow increases the scale of my raw footage as does the 2x resampling before alignment so I feel that some of your and Milton's comments apply to me as well.  I have imaged Jupiter without the Barlow in place and produced good images but when upscaled they did not seem quite as detailed.  There are so many variables I get a little overwhelmed.  I do regret that I must over sharpen the images in order to pull out details.  It makes them look rather grainy and produces a nasty ring at the edge of the planet.  Any processing tricks to eliminate them??

Looking forward to seeing your latest.

Phil

On Jun 19, 2006, at 11:23 AM, Alan Friedman wrote:

Phil -

Excellent! 

Are you using an unfiltered image for luminance?

Alan

On Jun 17, 2006, at 2:16 AM, Phil Houston wrote:

Here's another Jupiter image, this one showing Ganymede's shadow and 

 Io off tho the right of the planet. Imaging information follows.

 Time - 10;06 PM EDT - June 15, 2006

 Location - St. Petersburg, FL

 Seeing - 8/10

 Temperature - 81 F

 Winds calm

 Telescope - OTI Quantum 6, 2X Barlow, operating at F/42 ( roughly 6 

 meters) producing an image diameter of 283 pixels for 42.3" arc 

 planet . (.149 arc sec./pixel)

 Camera - DMK 31AF03 - monochrome CCD

 Luminance Frame

 Stack of 458/1019

 Gamma: 1.30

 Brightness: 756

 Black Point: 0

 Exposure: 66.67 ms

 RGB Frames

 Stack of 100/200

 Gamma: 1.30

 Brightness: 818

 Black Point: 0

 Exposure: 133.33 ms

 Image processing:

 Astro IIDC - Planetary, No fine alignment, 2X resampled

 Photoshop - Levels, Unsharp mask, Gaussian blur, RGB image was 

 produced, adjusted, and layered on the luminance image, final image 

 size was reduced.

http://www.knology.net/~pkh111/astrophotos/Q6jupiter.html

 Next time I will try Milton's and Alan's imaging and processing 

 suggestions.

 Phil