Limovie 0.9.25d has been released (Mar.3 2007)

New Features:

Gamma Reverse Correction
This function is the filtre to add the gamma correction to bmp image.
(1) Click “Gamma Reverse Correction” check box and check it.
(2) Input the gamma value which is considered to be added by video camera.
eg. Watec WAT100N :
Gamma Hi:0.45 Lo:0.60 OFF:1.0 ..... If the switch is selected Hi then gamma value 0.45 should be input.
(3) Then, the image is changed to gamma corrected. You can confirm the result of this effect using 3D graph function.
(4) Addition to, the Limovie's photometry works using this image, therefore the result of photometry is also “gamma corrected”. This means that videos pictured with gamma correction added by camera.
The pixel value (ADU) is decrease by this filtre. When measuring a faint star, the measurement region of Limovie may be difficult to track the target star. In such case, set the threshold to large value.

Fixed bugs:
“The coordinate of x and y recorded into CSV-file was incorrect” was fixed. (The problem was in only ver. 0.9.25)
“The central event time was incorrect” was fixed. (The problem was in only ver. 0.9.25)
“The anchor mode of star tracking doesn't work correctly” was fixed.

Using Limovie 0.9.25

<Download> Limovie 0.9.25d

Limovie Ver.0.9.25 has been released. This version has several new features to analyze the event time and light curve more accurately..

1.Using with Avisynth
Limovie became possible to read long video clip recorded as AVI Type1 file.
Thanks: Steve Preston discovered this useful method.

2.Multiple Object Measurement
This version is able to measure three objects simultaneously. It can be used to examine the influence of the scintillation of the atmosphere etc.
Thanks : Tony George suggested this function and checked this program.

3.Load CSV file
It can re-analyze CSV file.

4.Graph Draw
Spread sheet is not necessary for viewing the light curve any longer.

5.Fitting the light curve to diffraction simulation
This function gives accurate time, and inclination of lunar limb.
Thanks: Tsutomu Hayamizu checked this article and gave useful suggestion to explain more accurately.

6. Gamma Reverse Correction
This function is the filtre to add the gamma correction to bmp image.

Using with Avisynth

Limovie has limitation of “280 seconds” about the length of video clip.
Steve Preston had discovered the method to solve this issue. That is using Limovie with Avisynth.
He discribed how to use Avisynth on his website.

Using Avisynth with LiMovie : Steve Preston's website. There is mentioned detail of this method.

It is significant advance of Limovie. The method is possible to analyze long time video clip and also possible to read avi file which is compressed by DV codec. Dave Herald suggested the way to use Avisynth more easily. He said “I wonder ... have an option to read an avi file using Avisynth - with Limovie doing the necessary handling to avoid having to create a batch file each time.” Then, I improve Limovie to make .avs file automatically.

To read image by AviSynth, you must check the check-box of Use AviSynth in the "Update Setting Items". Please do this at first.

In environment which already installed AviSynth. The operation is same as previous version for usual file loading. When .AVI-file is selected by dialog box, Limovie makes AVS-file which has same filename as AVI-file, in the same directory as the AVI-file. And Limovie read .AVS-file automatically.

Obtain video file name : observation.avi
-> Make .avs file : observation.avs
-> Read video file (observation.avi)

If you want to edit .AVS file, Click "AVS File Edit" in "Option" in the main menu. It will be able to edit for your purpose, and it will be able to save it with arbitrary name.

Multiple Object Measurement

This version can measure three objects simultaneously.
Tony George suggested this function to know the influence of cloud or poor transparency etc. to compare other stars or sunlit point on the moon.

To add the new measurement region, please operate it as follows.

(1) Clicking right button on _another_ target star.
(2) Click "ADD Object" in popup menu.
(3) New measurement region is high-lighted, and it will be able to re-set its position by left-click on the target star.
(4) And it can be selected using Object1,2,3 button in the right of control area.

Graph Draw

This function is made to obtain the event time more easily.
When it is done clicking Start and Stop button of measurement, then click Graph button. The graph window drawn the lightcurve will be appeared. If multiple target is measured then multiple lines are drawn.
Find the point which indicate the central time of event( it has 25% intensity of full bright of target star ).
Clicke the point, then the image of video frame is changed to relative frame.
You can read the time of centre of event easily usinfg Field Show button.

Load .CSV files

This is the function possible to re-analyze the previous measurement. Especially, it does not need to spend your time to measure the long video clip.

Click [Load CSV] button and select the .csv file. Limovie load the data of previous measurement with reading the video clip (.avi file).

Graph function & Diffraction Fitting

If you have a video tape recorded grazing occultation event, operate as follows. The operation can be also used similarly at the case of general occultation and asteroidal occultation.

1. Click [AVI File Read] button
Select the .AVI clip and execute loading.

2. Click the target star on the image area
It will centre the measurement region on the target star.

3. Click [Start] button
Measure the entire of video clip if possible.

4. Save .CSV File
I recommend to save the .CSV file into same directory as .AVI file.
It will be able to load this file again when the program is re-started.

5. Click [Graph] button
The graph window drawing light curve is opened.
It display entire video clip.

6.Find the point of occultation event
Look at the graph and find the point which indicate the time of event.
Click the point. Then, the point is turned to red. And it is selected as a base point for diffraction fitting.
If you want to reset the selection, click the point again

7. Click [Part] button
The scale of X-axis is stretched. And the selected point is moved to the centre of graph.
And Click [Scale] updown button.
The scale of X-axis is expanded or reduced. I recommend to set to 4-16.

8. Click [Diffraction] button
The window of Fresnel Diffraction Analyzing is opened.

9. Set the lunar(asteroid) distance
# If you do not need to obtain the data of the contact angle, this setting is unnecessary.
Lunar distance is predicted by LOW(Lunar Occultation Workbench.)
Notice: Limovie needs the observer centric distance to calculate the diffraction effect. However, it is thought the numerical value obtained from prediction software is a geocentric distance. It can be used as an approximate value.

For asteroidal occultation
It can be obtained simply using the value of “Parallax” described to Steve Preston's prediction.
Distance = Radius of Earth / (Parallax(rad))
eg. Parallax=4.728" = 0.001313(deg) = 0.00002292(rad)
Distance = 6,378[km] / 0.00002292[rad]) = 278,200,000[km]

10.Set the lunar velocity
# If you do not need the data of the contact angle, this setting is unnecessary.
This is speed of shadow of lunar passed on the plane which is perpendicular to the direction of target star.

In grazing, this is obtained by the method as follows.
* IOTA prediction contains lunar velocity eg.
This velocity is displayed as position angle of circumference of lunar.
It is able to convert to [m/sec] as follows.
V = R * Pi * LV / (180 * 60)
V : lunar velocity [m/sec]
LV: lunar velocity [position angle/min]
R : lunar's radius [=1738000m]
Pi: pi [=3.14159...]
*As an example:

In the case of general lunar occultation
*OCCULT or LOW predicted "Radial Velocity(RV)".
It means the speed of change of diffraction effect.
If there is large angle between lunar limb and lunar direction, the lunar shadow, which has various density, is changed slowly.
The change speed slows in proportion to 1/cos(C.A.). (C.A.:contact angle)
Lunar Velocity which is requested by Limovie is at the case of "contact angle = 0", and also it is necessary to input contact angle to the edit box. However, it can be substituted by writing the “Radial Velocity" in the "Shadow Velocity" box. You need not write anything about the angle. (The angle is considered as 0.)
* As an example..
Radial Velocity(RV) = 0.396 "/sec
Lunar Distance(LD) = 378000km
Shadow Velocity(SV)
SV = LD * Pi * RV / (180 * 3600) <- It is "considered SV"
= 378000000 * 3.14159 * 0.396 / 648000 = 726 [m/sec]
Notice: Limovie needs the observer centric distance to calculate the diffraction effect. However, it is thought the numerical value obtained from prediction software is a geocentric distance. It can be used as an approximate value.

For asteroidal occultation
It is given by simple equation using the data which is predicted by Steve Preston.
V[m]=(Diameter[km] / MaxDuration[sec]) * 1000
* As an example.. (22)Kalliope at Nov.7 in Japan..
SV=181000 / 30.1 = 6103 [m/sec]
Notice: It is an approximate calculation. If you need more accurate result, especially when the movement of asteroid is slow, compute in consideration of the rotation of the earth.

11.Select [for Occultation / for Grazing] radio button
If you want to analyze grazing occultation then click [for Grazing]. It can also be used for analyzing asteroidal occultation.
[for Grazing] mode is able to calculate the contact angle of lunar limb. Therefore, we can obtain a information about geographical feature of lunar limb.
In the case of general lunar occultation, if you only need time data of event, I recommend to use [for Grazing] mode, because it is easier than using [for Occultation] mode. Limovie compute and fit the diffraction curve to the observed data.
[for Occultation] mode is used for doing measurement more accurately. (in the case of : Limovie obtained the rate less than 1.0 .. )

12.Click [Fit to Diffraction Curve] button
For a while.. The fitness curve is displayed. The yellow line indicate the centre time of event. And the cross indicate estimated error as one sigma.
The time is displayed on the Fresnel Diffraction Analyzing Window as offset time[millisecond] from the centre time of selected frame.

I think it is possible to obtain the event time with accuracy 1/100 sec or less using this method. Of course, without considering the effect of diffraction, using above procedure from No.1 to No.8, you can decide the event time more easily than using old version of Limovie.