Re: [APML] Erosion Filter (was M51 & M97)

[Matt BenDaniel <matt@starmatt.com>]

At 06:24 PM 4/29/2002 -0400, Mike Cook, AF9Y wrote:
>Brain,
>
>   I probably should have been clearer about the use of Erosion or Minimum
>filters.  This type of filter is useful to bring out a nebula area that is buried
>in a dense star field.  It works in a similar fashion to the rank order filtering
>by taken the minimum value in a neighborhood.  For objects with hard
>boundaries (like stars) it shrinks the size.  For extended objects like the
>nebula, the boundaries are soft and so there is little effect.
>
>   After reading the above, you can probably understand why Erosion would
>not be a good choice for a galaxy or any other image that has hard boundaries
>of fine, contrasting detail.

Mike,

Does it generally help to sharpen after erosion/minmum?

--
Matt BenDaniel
matt@starmatt.com
http://starmatt.com


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