Re: Data Disk Format

[hjohnson@pluto.njcc.com (Herbert R Johnson)]

I initially took about half an hour to read my Tech NOte #71, edit up
the three results by Tom, Andrew Bennett, and myself on Tom's dark images
from early Mark IV results, and to present a reply to Mr. Creager's
recent posted statistics and methods and Perl script. But
I decided that was a long way to say two things that can be said briefly
to Mr. Creager and indirectly to our colleagues.

First, **read Tech Note #71**. It shows methods and means that would be
informative to you, and to which you could compare your results, if you'd..

Second, use methods that are based on the **facts of the Mark IV images**.
Those facts are described mostly by Tech Note #71 and in part
by other Tech Notes.

One point I'd otherwise make specifically. I don't believe that you
can do useful statistics by looking at every single pixel of a Mark
IV image; some of them are "funny" and will screw up your statistics.
Also, I don't think you can do random statistics on raw images; there
are stars, hot pixels, dark current, sky background to consider. I
tried to reply in detail on these and other points, but I decided the
Tech Note already addresses these points, and better, so I deleted
such a reply and limited my comments to these.

In fact, I myself find most every point in contention seems
to be resolved, or at least informed about, in my TEch Note #71. This
is not because I  am a great writer or TASS experimentalist; it
is because I edited in good work by others and made some apparently
thoughtful comments. That was my intent, to make a REFERENCE Tech Note.

I wish more TASS members would refer to it and other TN's, to avoid long
and frankly misdirected discussions. Personally, the situation bugs me:
newly interested people should be directed to good information, to avoid
misunderstanding our work and to save everyone precious time. If I write
a Tech Note that does not accomplish that, tell me and I will fix it.

Herb Johnson

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