From: Alan Friedman <alan@greatarrow.com>

Date: May 31, 2010 11:35:34 AM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] memorial day star


Hi Ray,


Thank you! Yes, the disk of the sun is inverted. The prominences are captured in their own exposure setting - the disk is totally burned out at this point. When both are combined at a proper exposure for their relative brightness, the prominences appear much brighter than they would at the eyepiece (the eye does a much better job than the camera at accommodating the huge range in brightness, though the 12 bit depth of the PGR camera comes close.) Inverting the surface provides limb "lightening" instead of limb darkening. It's somewhat of an affectation, but I do like the feeling it creates. Of course I do have to put up with bright filaments and dark active regions, unless I reverse the values selectively as in this image.


cheers,

Alan



On May 31, 2010, at 10:27 AM, Ray Byrne wrote:

Hi Alan,


Lovely detailed and crisp image and beautifully presented as usual. Can I ask, do you invert the surface image (I'm assuming that this is a composite) as the limb is in fact bright when it is darker in the EP. If you do it is very effective I think I'll have a play myself with my recent images. I'd also like to be able to get a smaller image scale so I can get the whole disc on the chip of my DMK, my scope is slower at f/5.6 than yours so I may have to see if I can get a focal reducer or try my digicam.


Cheers


Ray


 

On 30 May 2010, at 21:09, Alan Friedman wrote:


Hi all,


!

Great to have a three day weekend after many weeks of work and no play. Here is a picture of our neighborhood star captured earlier this afternoon:


http://www.avertedimagination.com/img_pages/neighborhood_star.html


The Scorpion came ra used with the 450mm native focal length of my A-P Stowaway frames the full solar disk nicely. Process in Astro IIDC and Adobe Photoshop CS3.


best wishes,

Alan