Re: [APML] Orion Mosaic

[Axel Mellinger <axm2@canopus.physik.uni-potsdam.de>]

On Sat, 29 Jan 2000, Philip Perkins wrote:

> Do you scan at high resolution (say 2700 dpi)?  I am interested in knowing
> the original resolution of this image, before downscaling for the web.

Philip,

the images were scanned at 2700 dpi. The original resolution of the mosaic
is 6000x6400 pixels (a 115 MB file!). The advantage of this high
resolution is that I can increase contrast quite substantially.
There is posterization in the high-res image (the histogram shows
significant gaps), but when I scale the image down by a factor of two
(which is still good enough for slides and 8"x12" prints), each pixel in
the new image will be an average of four pixels in the high-res image.
This smoothes out the histogram.

Clear skies,

Axel


-- 
Axel Mellinger  <http://canopus.physik.uni-potsdam.de/~axm/astrophot.html>


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