Re: tricolor strip

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

On Wed, 08 Apr 1998 14:57:29 -0700, Chris Albertson <chris@topdog.pas1.logicon.com> wrote:
*>
*>I have thought about creating a synthetic image from the TASS Database.
*>Not a plot but a real image made by convolving a PSF with the points

presumably you mean points from the database. Good idea.

*>It would be in color and look like a photograph taken with and an ideal
*>wide field camera.  The point would be to show this picture when you

One challenge is to choose the colors. As we are using VRI filters,
what visible colors do you map them into? COlor mappings are an old
subject: false colors can look like psyedelic posters and be distracting.
It's an art, not a science. I'm glad the color "seperations" are available
for experimenting.

*>say that a TASS camera site can measure 100,000 stars in one night.
*>Then you show the synthetic image with 100,000 stars.  I'd also
*>have a bound set of papers holding the data that corresponds to the image.
*>It would look like a small phone book.  Next you say "every site collects
*>this every clear night".

Regarding the "phonebook": Simple enough to do the arithmetic. HOw many
database points per printed page, using one line= one record, and
a "standard" of 60 lines per page? (Or you could use the phonebook font
and format if you wish). But 100,000 / 60 is about 16,700 typed pages.
A ream of 20 lb paper (500 sheets) is about 1.75 inches tall. 8,350 sheets
is 16.70 reams or about 30 inches tall (rough math here).

A phone book format is 4 columns of about 100 lines each. *IF* you assume
two lines per data point, then one page is 4 * 50 = 200 data points.
So 100K points is 500 pages, 250 sheets. I measure that as 1 cm of paper,
maybe 3/8ths inch thick. A small town (of 100,000?) phone book.

But tell your audience this is only a narrow strip of sky.

These measures can be used for other data sets, if you trust my premises.
I'd check the math.

Herb


  **** ------------------------------------------------------ ****

Herbert R. Johnson                      voice/FAX 609-771-1503 day/nite
hjohnson@pluto.njcc.com                 Ewing, in central New Jersey, USA

                 amateur astronomer and astro-tour guide
            supporter of classic S-100 computers as "Dr. S-100"
        rebuilder of Mac Plus computers for your computing pleasure
     and senior engineer and asteroid spotter at Astro Imaging Systems