Re: TASS object follow-ups

[Herb Johnson <hjohnson@pluto.njcc.com>]

Tom makes a good point that is worth some details. For a typical 
Schmidt Cass, using a typical CCD camera, the field of view of any
image at prime focus is tens of arc MINUTES. Whereas, if I recall the
Mark IV field of view is about four arc DEGREES. This makes most amateur
S-C's poor instruments for the wide field survey work that Mark IV
(and Mark III) perform. But the larger aperture of the S-C means they
can look deeper, or require less exposure time than the Mark IV. These
are advantages when following and measuring TASS objects like variables,
or even those "planet eclipses" that are under consideration. I would
encourage my TASS colleagues to discuss these differences further. It
is a double challenge to prospective TASS members to not only figure
out what TASS is doing and how, and then to determine how *their* 
instruments can participate. Current TASS members can make both tasks
easier by discussing these and other differences, and how complimentary
projects, even ones that are apparently simple, can be effective and
useful.

Buried among the TASS Tech Note are some of the instrumental considrations
of Mark III and Mark IV, and implications as to how they affected the
results from either instrument. These may be helpful to all involved. I
myself plan to work on Mark III stuff in this new year.

Herb Johnson

Herbert R. Johnson              http://pluto.njcc.com/~hjohnson
hjohnson@pluto.njcc.com         voice 609-771-1503, New Jersey USA

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