Lightcurve Analysis in Canopus
Industry Standard Analysis
The Photometry page of the Canopus application displays the data for lightcurve
analysis. The routine is a translation from FORTRAN code of Dr. Alan Harris of JPL for use
in Canopus. This routine is considered a standard among professionals for lightcurve
The entry fields at the top of the page and other controls allow you to "zero
in" on the period with the help of the Period
Spectrum form, which lets you see a range of possible solutions.
Observations from night to night and even among observers can be combined to produce a
single set of data.
Canopus was the first program to incorporate this
algorithm designed for general use by amateurs (and even professionals!). It has been used
by observers world wide for the past decade to publish almost 2000 lightcurves in juried
publications. There is no substitute for a proven track record
Simple and Efficient Measurements - Start to Finish in 20 Minutes
Using the Lightcurve Wizard in MPO Canopus, you
specify up to five comparison stars and the target on two images, usually separated in
time by an hour or more. Once this is done, you select all the images you want to measure
and start with the first. Canopus automatically tracks the motion of the asteroid and
adjusts the position of its measuring apertures image by image. If you have a mount with
good tracking, the only time you may have to reset the position of all apertures (with a
single mouse click at that), is if you periodically adjust the scope's position to keep
the asteroid centered. Those working a fixed target such as a variable star can often go
through an entire night's images without ever having to reset the apertures.
In short, what this means it that starting with 150-300 images from a night's run, you
can setup the wizard, measure the image, and do initial period analysis in less than 20
minutes while maintaining full control over which images are actually measured. This
allows you - not the computer - to determine if a plane going through the middle of an
image affects the measurements or not. Time saved by automatic measuring can often be lost
when trying to determine why some data points appear to be "out of whack."