The International Occultation Timing Association's 37th Annual Meeting

in conjunction with the Riverside Telescope Makers Conference (RTMC)

Big Bear, California, September 21, 2019

  by Richard Nugent, Executive Secretary


The 37th annual meeting of the International Occultation Timing Association was held Saturday September 21, 2019 at the Riverside Telescope Makers Conference (RTMC) in Big Bear, California. The meeting was kindly hosted by Martin Carey, President of RTMC. RTMC is one of the world’s largest telescope conferences and trade shows.  

The  meeting schedule and agenda are located on the IOTA web site presentation page:



..........................................Homer F. Daboll, David E. Laird and Lifetime Achievement Award winners


Left to right: Homer F. Daboll awared winners: Dave Gault, Jan Manek, Mitsuru Soma.

David E. Laird award winner: Jim Stamm

Far right: Lifetime Acheivement award recipient: Paul Maley


Attendees: President Steve Preston, Vice President Dr. Roger Venable, Executive Secretary Richard Nugent, Drs. David and Joan Dunham, Jerry Bardecker, John Moore, Bob Jones, Chuck McPartlin, Anna Venable, Steve Edberg, Blaine Herbert, Wayne Thomas, Bill Hanna, Daniel Derose, Russ McCormick and others.


 9:10AM – Meeting start


Vice President Dr. Roger Venable opened and welcomed everyone to the meeting. After inroductions, the business meeting began.


Business meeting:


Treasurer Joan Dunham presented IOTA’s financials and membership status. Previously to 2019, the Journal of Occultation Astronomy, JOA was only available to paid members. By unanimous agreement with the IOTA regions in North America, Europe and Australia, JOA became a free download to anyone.

Expense report: A summary of the year’s income/expense report (mid April 2018 to September 15, 2019):



  • Membership (JOA print subscription) ....$860.52
  • Online only ...........................................$1452.20
  • Royalties (VTI & RunCam sales).......$12857.21
  • Donation..................................................$125.00
  • Interest.........................................................$7.88
  • TOTAL INCOME................................$15302.89


  • JOA Production.....................................$2784.20
  • VTI Production...................................$10980.00
  • Bank fees ..................................................$53.85
  • Awards....................................................$430.27
  • TOTAL EXPENSES...........................$14238.42

NET Income: $1054.87


IOTA Membership and Subscription:

Membership with print copy of JOA - 17

Membership only -86

Library membership - 2

North American (USA and Canada) members -99

Other (India, Australian, New Zealand, European) - 6

Net membership increase since last meeting: 18


  • .......................................................... VTI and RunCam Inventory
  • .............................................. Ready for Sale ....................... In Fabrication
  • ...............................RunCam .......... 34
  • ...............................Focal Reducers ..8
  • ...............................VTI ................... 6 .......................................... 27
  • .............................. SVID2USB23 . 12

Joan mentioned there are sufficient parts (cables, adapters, battery holders, etc.) to complete new kits as orders arrive. A future purchase being considered is a 3D printer to make camera carriers that fit 2" focusers for RunCams.


Executive Secretary Richard Nugent presented IOTA’s election results. Officer elections are held every 3 years as per the by-laws. All current Officers with 2 changes agreed to continue and the election was announced on the IOTA list server with voting open from September 3-15, 2019. The 2 changes were: Joan Dunham took over as treasurer after Chad Ellington resigned after 12 years of service. Chad Ellington's service as IOTA's Treasure was held in the highest regard by its members. John Moore took over as VP for Planetary Occultation Services following Brad Timerson's passing last year. The voting was unanimous and the Officers were re-elected into their respective positions:


President: Steve Preston
Vice President: Roger Venable
Executive Secretary: Richard Nugent
Secretary & Treasurer:: Joan Dunham
V.P. for Grazing Occultation Services: Mitsuru Soma

V.P. for Planetary Occultation Services: John Moore

V.P. for Lunar Occultation Services: Walt "Rob" Robinson
Director: David Dunham


Richard Nugent then presented the IOTA’s Homer F. Daboll, David E. Laird and the Lifetime achievement awards. No awards were presented in 2018 thus several awards were presented this year. The Homer F. DaBoll Award is given to recognize significant contributions to the field of occultation science and to the work of IOTA. This year's recipients are the Lunar/Asteroid occultation coordinators: Mitsuru Soma from Japan, Jan Manek from the Czech Republic and Dave Gault from Australia.


Mitsuru Soma is recognized for collecting and analyzing graze observations worldwide, producing World maps for asteroidal occultations, for his many years of regional coordination of IOTA lunar occultation observations and his continuing contributions of occultation measurements.


Jan Manek is recognized for his many years of regional coordination for IOTA lunar and planetary occultation observations and continuing contributions of occultation measurements.


Dave Gault is recognized for his many years of regional coordination of IOTA lunar occultation observations, his immense work in archiving and correcting errors with thousands of graze and asteroid observations and continuing contributions of occultation measurements.


The David E. Laird award is given to recognize those who, more than 15 years ago, made significant contributions to occultation science and to the work of the IOTA. This years David E. Laird award recipient is Jim Stamm from Arizona. Jim is recognized for his many years in collecting and publishing asteroid occultations reports and results worldwide, providing the lists of asteroid events for the RASC Observer's Handbook and being an active regional coordinator for IOTA's lunar grazing occultations.


The IOTA Lifetime Achievement Award is given, as needed, to recognize outstanding contributions to the science of occultations and to the work of the International Occultation and Timing Association over an extended period of the recipient's lifetime and is conferred by the IOTA Board as needed. This year's Lifetime Achievement Award 's recipient is Paul Maley. Paul is recognized for leading IOTA's formal incorporation in Texas, for his worldwide efforts in the coordinating and observing of lunar, asteroid occultations plus solar eclipses, and for his outstanding efforts to encourage and educate people in many countries to observe occultations.


For information on IOTA's awards, including previous awardees, see the award webpage:


Technical sessions:


John Moore discussed the Pluto occultation from August 15, 2018 and the use of fixed observatories for such high value occultations. Steve Conard had contacted some of the larger observatories in the path to help record the event. Near to the center of the path was the George Observatory south of Houston. It houses a 36" telescope in the main dome, a Celestron-14 and a 16" f/6 in it's west and east domes respectively. For the event, Ted Blank drove there and made the observation assisted by long time George Observatory volunteer Tracy Knauss. Through the 36" Pluto was bright, the atmosphere was steady and the resultant light curve of the occultation showed the central flash clearly (see JOA, 2019-3, page 14). Also at the George Obs. was Paul Maley and David Haviland who made the observation using the C14 in the west dome. At Louisiana State University (LSU), John Moore had contacted the Baton Rouge Astronomical Society and arranged to make the observation using their 0.5m Ritchey-Chretien telescope. The night before the event, John was invited to give a talk at the BRAS on occultation activities and the Pluto event where there was a lively Q&A session afterwards. 


Steve Conard and Roxanne Kamin made arrangements with Dr. Scott Long to use Liberty University's 0.6m telescope to record the event. Roxanne made the observation alone with her personal QHY 174M CCD camera (with built in GPS timing) that has a programmable frame rate. She used a 250 ms recording rate and was able to record the central flash. This camera can be set to an exposure rate of 0.010sec (and lower) which equates to a 100 frames/sec. There is an issue in using the camera at very high frame rates which has resulted in many dropped frames, sometimes 10% (and more) of the total count.  John thought that the dropped frames might be a software issue or the FOV size, which he eventually thinks can be resolved. 

Steve Conard made the observation at the Lynchburg University’s Belk Astronomical Observatory. The original plan was use the observatory's 0.6m RC scope however with multiple  issues the night of the event (laptop wouldn't connect, tracking didn't work, etc.) and at the last minute Steve chose to use their 0.2m SCT telescope. It was quickly setup using a Watec 910-HX plus the IOTA VTI. Steve and the volunteers were thus able to make a successful observation.  


Richard Nugent presented a talk, "RunCam Zoom Feature". A little known feature of the RunCam camera is the "zoom in" setting which magnifies the image with 6 levels of zoom from 0 to 5. The zoom feature is on the opening screen (2nd from bottom). If you're trying to resolve close double stars, the higher zoom helps resolve the components. Richard made several 30 second videos of an individual star, increasing the zoom every 5 seconds. From one video, he used Limovie to measure the brightness of the star:




The above light curve shows the surprising result after using each zoom step from 0 to 5 - the brightness increase was 3.2x corresponding to a 1.2 magnitude increase. This was an expected result as the star's pixels were enlarged within the area of Limovie's aperture rings. Use of the zoom feature can help increase the S/N ratios for fainter occultation targets and significantly aid in the light curve analysis. This can avoid using RunCam's Night Shutter option (frame integration) to reach fainter objects which causes time loss resolution.

David Dunham talked about the 3200 Phaethon occultation from July 29, 2019 visible over California and Nevada. It's the target of the Japanese Space Agency's (JAXA) DESTINY flyby mission in 2025, hence the need for occultation observations to provide an accurate position to refine it's orbit for the  mission. Phaethon is of interest to planetary astronomers since it is the parent body of the active Geminid meteor shower. Phaethon's small 5km size made predictions a challenge. The plan was to have 66 stations spread out over 45 km plus 4 more outside this range. Of this total  9 stations couldn't be filled, and 11 didn't get any data. David and Joan Dunham set 11 stations of which 7 got data. Other observers were Scotty Deganhardt: 6 stations, Steve Preston (5 stations, 2 worked), John Moore/Steve Whitehurst (9 stations, all worked), R. Howard (3 stations - all worked), Jerry Bardecker (2 stations, 1 worked).  A total of 52 stations got data and 11 stations failed for one reason or another. Here's the resulting occultation profile:


- - -Break - - - Several demos of telescopes and equipment setups - Joan Dunham's video setup, Roger Venable's occultation box, David Dunham - paver mount scopes.


Joan Dunham spoke about "Inexpensive Video Recordings for Precise Timing of Occultations". Joan showed several video occultation setups using several small tablets and the iView computer and how she installs the software and selects codecs. Joan prefers to use computers to capture videos since there is usually no data compression. Digital video recorders (DVR's) can be used for recording videos, however some models do suffer from undesirable data compression and/or frame duplication or even frame loss. For timing, Joan showed that you can record without a VTI by using a cell phone flasher triggered by GPS signals. Android phones use the Occult Flash tag and iPhones can use the AstroFlashTimer written by John Grismore. The flasher concept has a flashing LED placed within the FOV so the camera can record the flashes. She talked about cost considerations for setups: Computer 0-$200 (used/refurbished laptops), Windows tablets from Amazon can be acquired for under $200,  Timing: IOTA VTI-$249, Arduino Ticktoc $20-$40, Cell-phone GPS flash tag - $0 from Google Play.


David Dunham went over future asteroid occultation events for southern California through October 2019 which was provided as a handout for the meeting.  He also showed a list of total lunar occultations and some grazes visible in the 10 days following the meeting over southern California. One such occultation is of mu Geminorium on the morning of September 23 m= +2.9 which occurs after sunrise. David mentioned it could be visible from a Celestron 8 or large scope. 

Asteroid events over southern California:

200 Dynamene asteroid event m - 10.8 Sep 24 is centered over the greater Los Angeles area. 

598 Octavia Sep 26, m= 7.8.

3200 Phaethon Sep 29 over Lancaster/Palmdale

16 Psyche Oct 24 - largest "M" type metal asteroid target of NASA mission.


12 Noon ---lunch break----


David Dunham then showed his Baily's beads video from the July 2, 2019 total eclipse from Argentina. He was located at the southern edge and coincidently his hotel was positioned right on the he and Joan observed from their hotel on the roof. He next showed a combined video recording of the Aldebaran occultation from 5 stations on March 5, 2017 made by the North York Astronomical Association in Canada. The spectacular video is here:


Steve Preston explained how Hristo Pavlov's program Occult Watcher (OW) works.  By entering a position, and a specified radius OW will list all asteroid occultation events occurring within that radius for a specified time range. The user can also specify a minimum altitude for the occultation (from that position) so it the target won't be blocked by buildings, trees, etc. From input by many of its users, Hristo is working on several updates. He's also considering writing an android app for the program. OW lists the magnitude, max duration of the occultation, rank, travel distance to the predicted center, azimuth of target star, date the prediction last updated and the source of the prediction. When you pick an event, OW shows a map of all observers signed up for the event so you can choose a location that doesn't duplicate other observers.  The attendees told of their experience with OW and their suggestions for changes/things they'd like the program to do.


Roger Venable showed a spreadsheet he uses to plan his remote station pickup after an occultation. For the number of stations he computes the driving time between stations and how long it takes him to gather/pick up the telescopes/equipment. Roger knows specifically how much time he has to pick up his stations depending on their total separation and the start of civil twilight. Near civil twilight and closer to sunrise the stations become visible ands are subject to onlookers/theft.


Russ McCormick described the IOTA Video Capture App Version 2.2. A zip file of how to setup and use the video capture method is here:


 It records video from attached USB devices. The video is stored in AVI files on disk. Output is AVI 2 files only which supports dropped frames. For manual recordings the app requires the user to be present. The app allows scheduling of events, recording duration, various display filters, star no., asteroid and other settings. Display options available are: display brightness/contrast, pixel saturation, frame integration, magnification and crosshairs (which can be overlaid). Crosshair location and intensity are available both during the recording and during playback. Other options include a countdown timer to start the recording, display on/off, remove display filters while recording, "timer off" when a recording starts, automatically start GPS if connected, enable brightness/contrast in video file and a beep upon start/stop event recording. Russ showed a demo (camera showing the meeting room) and how the various settings affect the display. Video capture playback has buttons to go the beginning or end of video, start/stop, fast forward, reverse and frame by frame advance.


Russ is currently working on Version 3, with an expected release sometime in 2020. The new version should support multiple file types AVI, ADV, FITS 2D, 3D and SER.  This version will only support Windows 10.


Roger Venable  showed his video of 216 Kleopatra which had a double event from the tips of both ends its dogbone shape. When using Limovie he suggested removing the checkmark st the "Synch APT" which effects the "jump" capability of the apertures in trying to stay on the star. He then demonstrated PYOTE using Limovie's  CSV file from this video. PYOTE has the ability to "trim" the light curve and improve on the quality of the analysis. After a few clicks, he had the D and R times with PYOTE's error analysis. Roger commented that manually entering the start/end VTI times was easier than reading them from the CSV file, since Limovie usually cannot acquire the times from video frames.  


Joan Dunham played her July 2, 2019 eclipse video and the "tick-tock" timing centered around totality.


The Meeting adjurned at 3:50 PM and the attendees continued their discussions. An IOTA booth was set up outdoors on Friday and Saturday similar to the one in 2018 at NEAF. Equipment demos, and flyers were available to visitors. This was IOTA's first outdoor booth.


                              The minutes of IOTA's annual meetings are at:




The International Occultation Timing Association is the primary scientific organization  that predicts, observes and analyses lunar and asteroid occultations and solar eclipses.  IOTA astronomers have organized teams of observers worldwide to travel to observe  grazing occultations of stars by the Moon, eclipses of stars by asteroids and solar eclipses since 1962.