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Date: 28 Jul 2006 18:21:27
From: Ioannis
Subject: Ping Chris Peterson


Chris,

Long time ago you helped by suggesting the program Iris for converting from
.jpg to spectrograms.

One of the instructions was to convert the color spectrum to a 8-bit/channel
black and white .jpg and use the slice tool.

It never occurred to me during all this time, but today I tried the slice
tool on the original colored .jpg's and it works fine also. The results look
almost identical as if I used the slice tool on the black and white .jpg.

Is the conversion color .jpg- > b&w .jpg really necessary?

Thanks much,
--
Ioannis





 
Date: 28 Jul 2006 15:39:41
From: Chris L Peterson
Subject: Re: Ping Chris Peterson


On Fri, 28 Jul 2006 18:21:27 +0300, "Ioannis" <morpheus@olympus.mons >
wrote:

>Chris,
>
>Long time ago you helped by suggesting the program Iris for converting from
>.jpg to spectrograms.
>
>One of the instructions was to convert the color spectrum to a 8-bit/channel
>black and white .jpg and use the slice tool.
>
>It never occurred to me during all this time, but today I tried the slice
>tool on the original colored .jpg's and it works fine also. The results look
>almost identical as if I used the slice tool on the black and white .jpg.
>
>Is the conversion color .jpg-> b&w .jpg really necessary?

Probably not. When I suggested that I was probably assuming that the
tool only worked on B&W images. The problem with doing this at all is
using a color sensor, and JPEG images. But those problems are to do with
trying to get quantitative results. I seem to recall that you were
primarily looking at qualitative data, or at peak positions. Of course,
you could probably get fair quantitative data if you could calibrate
your sensor and process, so that you could apply a fixed weight to each
wavelength.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com