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Re: [APML] Near and far... NGC 300 (8k x 8k)

Dear Mischa,

      These images are so large that some Macintosh graphics programs 
will not display either the full or half-resolution versions.  For 
example, when attempting to open even the half-resolution version 
using Apple QuickDraw routines, these programs display the following 
error message:

      "The width of the document "XXXXXXX" exceeds the MacOS QuickDraw 
limit of
      16383 bytes or pixels per line.
      Source width:  4300
      View pixel range from 1 to 4088"

This suggests a very slight cropping of the picture in the default 
horizontal position -- from 4300 to 4087 pixels --  would make it 
(the half-res version) viewable by any of these applications.

      Thanks for the effort you have already put into these pictures. 
They are spectacular!

Yours, cordially,

Paul Rybski, Physics, Univ. of Wisconsin-Whitewarter, USA

>Hi,
>
>maybe you enjoy this deep wide field shot of NGC 300,
>taken with ESO's Wide Field imager at La Silla, Chile.
>I like very much the transition from the outermost fringes of
>NGC 300 (distance: 9 million light years) into deep, deep space.
>You can count apx 75,000 faint background galaxies out there.
>
>I didn't observe this target by myself, instead I downloaded the
>publicly available images from the ESO archive and run them thru
>our data reduction pipeline. Calibrating, aligning and coadding
>the 3016 single FITS files was quite a bit work, but I found the
>"Photoshop science" even harder.
>
>For this LRGB color composite I multiplied the summed H-alpha channel
>5 times and added it to the R filter, yielding the red image.
>
>For the Luminance channel I coadded the blue, green and red channels
>and DDPed them. With the lasso tool in photoshop I selected the inner
>third of the galaxy and brought it down to lower brightness by
>adjusting the curves a little bit. I repeated this step a second time
>with the galaxy core.
>In a similar fashion I selected everything outside the galaxy and
>increased the brightness of the faint background galaxies.
>
>For the RGB layer I created and merged two RGB images. The first
>showed the color well for the galaxy without saturation, but of course
>almost none of the background objects was seen. The second image
>showed the color of the background fuzzies very well but saturated
>the inner half of the galaxy. Merging these two images (with a smooth
>transition) and combining it with the previously done Luminance
>channel gave the result.
>
>Check it out:
>
>http://www.astro.uni-bonn.de/~mischa/NGC300
>
>I think the full resolution version is well worth the long
>download time.   :)
>
>Best regards
>
>Mischa Schirmer
>
>
>
>
>
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________________________________________
Paul M. Rybski, Ph.D.
Associate Professor and former Chair, Dept. of Physics, and
Director, Whitewater Observatory
University of WI-Whitewater
Whitewater, WI  53190-1790

Office FAX:     (414) 472-5633
Email address:  rybskip@uww.edu

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