Software

Occult v4 – This is the current fully-operational suite of freeware software created by Australian 
author Dave Herald for the prediction and reduction of lunar and asteroidal occultations. It is written 
for Windows OS.  It has a completely new GUI and lightening fast implementation in C# program language. 
It also adds the new functionality of mapping compatible with Google Earth and Google maps, a new lunar 
graze reporting form, and new lunar graze historical database. The asteroid occultation prediction routine 
automatically downloads and unzips the massive MPCOrb and Astorb databases.

VirtualDub – This freeware program is for capturing and pre-processing .avi video files. Many use this 
program to create a uncompressed video file compatible with Registax and LiMovie.

Avisynth -- AviSynth is a very very powerful freeware tool for video post-production. It provides almost 
unlimited ways of editing and processing videos. AviSynth works as a frameserver, providing instant and 
very fast editing without the need for temporary files. Many are using Avisynth as a scripting tool and 
preprocessor for use in LiMovie.

LiMovie – This outstanding freeware program written by Kazuhisa Miyashita is used to obtain photometric 
data from occultation videos. It can determine the photometry for up to 3 different stars simultaneously. 
There is a graphing function that includes a Fresnel Diffraction based occultation timing function for 
lunar grazes, lunar total occultations, and asteroidal occultations.  It is possible to link the tracking 
of faint stars to brighter stars within the field to allow getting photometry of stars otherwise too faint 
to track.  It is also possible to extract time stamps from KIWI or other GPS time stamps and/or WWV audio 
time stamps.

LimovieAverage – a new program written by Dave Herald to allow the correction of Limovie csv data files 
so that interference from clouds, haze, atmospheric extinction and other observing artifacts from really 
long mutual event observation files.

Registax – Another outstanding and indispensable freeware program, written by Cor Berrevoets for the advance 
processing of video and multiple images. The software stacks and processes video and multiple single images 
to achieve unparalleled sharpness and resolution. For occultations, Registax provides a “pre-registration” 
function that aligns the many frames in a video image to compensate for windy conditions when individual 
frames are dancing in the video frames so violently that LiMovie cannot attain proper photometric results. 
Even more useful, Registax provides an “integration” function that will integrate multiple frames in the 
video in a ‘running average’ format, which preserves the frame-by-frame timing of the video, but enhances 
faint stars and suppresses noise. The integration function can increase the sensitivity of the CCD video 
camera while preserving the 1/60 or 1/30 second time resolution.

Occular 4.0 – A program written and co-authored by Bob Anderson and Tony George. It provides a new methodology 
for analyzing LiMovie .csv output file to determine the time of disappearance, reappearance, and duration of 
asteroid occultations in a semi-automated routine. Occular is extremely adept at finding very weak or very 
short occultation signals in videos that would otherwise be very difficult to process manually or visually.  
Occular 4.0 updates previous versions (Occular 3.14 and Occular 2.09) to include sub-frame reading accuracy 
of high SNR event, transitional timing of extended D and R events lasting more than one frame, in-program 
frame block ‘integration’ and/or moving average integration, and a data integrity checking routine – helpful 
for catching dropped frames and/or Limovie time stamp transcription errors.