Fast Focus feature
This is an experimental feature.
This feature can be used to focus.
The CCD is read out with a high speed, you get a trail of the object.
This trail is evaluated in time and the results are shown on the screen.
The tracking of the telescope is on.
Place a bright object on the CCD(about mag 1), near the top of a standard image.
There should not be any other bright objects at/near that columns.
At fist, when starting the fast focus function, a FastSearch function is used to find the brightest object on the CCD,
the start of the planetary mode then is set automatically.
Chose Camera - Settings .
Declination, Focal Length, Sidereal Rate no entries required for this kind of imaging.
First select the FastFocus Tab Sheet!!!, there are used different settings for this
CCD - imaging CCD or tracking CCD - the CCD you want to use
Binning - using the imaging CCD of a ST-7 or ST-8 1 x 3 vertical binning - should be used
Planetary mode - Start 50, Length 40
Focus (check Box) - not checked
Light or dark frame - light frame
Auto Grab number of images - 1
Brake during taking an image - enabled
At the bottom of the form at the left, there is a Page Control
Chose the FastFocus Tab Sheet
Time per line - about 0.0015 sec per line, depends on the brightness of the object, may be set to a low value
There are also some entries required for the fast search mode:
First select the FastSearch Tab Sheet!!!, there are used different settings for this
CCD - imaging CCD or tracking CCD the same CCD selected for FastFocus
Binning - using the imaging CCD of a ST-7 or ST-8 3 x vertical binning , 6 lines- should be used
Planetary mode - No
Focus (check Box) - not checked
Light or dark frame - light frame
Auto Grab number of images - 1
Brake during taking an image - enabled
At the bottom of the form at the left, there is a Page Control
Chose the FastSearch Tab Sheet
Time per line - about 0.0015 sec per line, depends on the brightness of the object
Then chose: Camera - FastFocus
An other form is shown.
You can change some settings in this form.
Press the Start button.
To stop press ESC .
After starting, the values of FHWM, Moment, Peak value and a 2D profile of the trail are shown.
The easiest way is, to look at the 2D profile and change the focus, until you get a small profile
Or look at the values until the values of FHWM and Moment are at the minimum and the value of
the Peak value is at the maximum.