|
Mirko,
Depending on your setup it can take between 120 sec and 9 sec.
If you just let the solar disk drift across the slit it's 120 sec. If you use the slew buttons on your mount (ie x2 or x3 sidereal) you can get down to 9sec.
The other issue is obtaining sufficient frames during the scan video.
The size of the solar disk is close to 1/100 the telescope focal length. An ED80 for example gives a solar image of 5.6mm, using an ASI 178 camera with 2.4 micron pixels this equals 2327 pixel.
To get a pretty close to circular scanned image (to minimise geometric corrections) you then need to record approx 2327 frames. This leads to a frame rate of 2327/9 = 258 fps.
(With the drift method you'd only need 2327/120 = 19.4 fps)
Hope that helps.
(Oh, it takes around 3-4 sec (!!!) to process the video into an image. The INTI software is very fast.)
|