[Aavso-photometry] SSP-4 photometer available for loan

[arne]

The AAVSO has five Optec SSP-4 near-infrared single-channel photometers
that we load out to members who want to try something new and different,
and at the same time support continued monitoring of stars in the NIR.

These photometers look identical to an SSP-3; very compact, simple
devices.  They come with two filters: J (1.25micron) and H (1.65micron).
Simple software gets the data into your computer, and the AAVSO HQ
PEP software can process the raw data for you.  Very simple!

At the same time, the simplicity means that you have to handle this
device manually.  There is a flip mirror for acquisition and centering
using an eyepiece; and a two-position filter slide that you have to
move manually.  In other words, without modification, this is a system
where you have to be at the telescope.  You cannot work very faint, but
most Mira and LPV stars are very bright in the NIR, so this means the
majority of your targets will be red variables.  Like other PEP measurements,
it will take you 15minutes to an hour per object to acquire one datapoint,
again not a problem with long period variables, but meaning that you won't
observe too many stars on any given night.  It is also a device that
requires photometric skies since you have to physically move the telescope
to the comp star as this is a single-channel system.  However, you
don't need good seeing, and light-polluted skies are usually no problem.

However, it is simple to use, and requires very little computer skill to
operate.  We currently have a varied program of objects, but the primary
goal was to support the long-term monitoring of Miras that Patricia
Whitelock was doing from South Africa.  As more professional telescopes
switch over to NIR array detectors, the brighter stars become more and
more neglected.  The initial observations targeted a variety of stars
to see where the systems would be effective, but we will be giving
a more definitive program for the SSP-4 systems in the near future.
Also, there will be campaigns like the upcoming epsilon
Aurigae eclipse, where NIR observations will be extremely important.

These systems are given out on long-term loan to members.  We ask only
that you use them for AAVSO projects, maybe not every night, but often
enough that they don't gather dust.  We have two that are available for
immediate loan: one in the northern hemisphere, and one in the southern
hemisphere (with priority for Australia).  If you think you might be
interested in either system, email me privately.  Note that, while I
say they are loaned to members, you can easily join the AAVSO these days,
and the price of membership is far less than the US$3000 cost of the SSP-4!
Arne