CCD vs Film? Lots of time vs no patience? Alright, this is your place to discuss all the astrophotography what's and what's not. You can discuss about techniques, accessories, cameras, whatever....just make sure you also post some nice photos here too!
hm...motor tracking. i don realli understand d term motor tracking. does d mount auto track d object? or do u need a recticle to track d object and at d same time guide it? thanks alot.
Normally, tracking is not actually tracking. The motor drive is turning at the same rate as the earth rotation, so that the scope seem to be tracking the star (provided accurate polar alignment). This type of open-loop tracking is normally use for visual, short exposure and wide field astrophotography, because it can't "track" accutrate for a long time due to mechnical and alignment error.
For long exposure astrophotography, normally you need to do guiding which provided the feed back (closed-loop) to the motor. It can be done manually or automatically (via Auto-guider) using either a guide scope or a off-axis guider.
Since he use a Webcam, he can see the jupiter in the computer screen. He can just put the jupiter at one corner in the Field of View, start the capture software and let the jupiter drift across the screen. At 25 Frame per second, he just need 36 second of video to get the 900 frames. No motor is need actually.
Have a nice day.
Yang Weixing "The universe is composed mainly of hydrogen and ignorance."
ariefm71 wrote:btw, if you're using avi with registax, how do u get the individual frames to choose the good ones? my registax does everything automatically
registrax can separate out each and every frame so that you can view them individually. You then choose the ones u think are good...
900 frames will take a long time to sort through, but the results are worth it.
Hi all,
As what the other menbers here says, motor tracking is actually we use a motor mounted on our eq mount's R.A axis. When the motor move, R.A axis will rotate from east to west to act as follow the sky motion and this is so called motor tracking. Once your eq mount is set proparly, then the can well track the sky.
Why I said it is better to have motor drive tracking system on your eq mount? It is because by using the method of putting a planet on one of the corner of FOV is not so good. This is because you have to speed up the fps rate and images captured will be compress too much and will loss some detail. After some experiment done, ToUcam is best to set at 10fps and 5fsp.
If seeing is good, we do not need to capture up to 1800 frames. Due to Jupiter's rotation is fast at 9.8hours per round. So we cannot take too long to prevent errors that may occur while stacking them up.
No matter how steady your hand are, you will cause vibrat on your eq mount at high magnification condition. If not believe, try it out.
Why I said it is better to have motor drive tracking system on your eq mount? It is because by using the method of putting a planet on one of the corner of FOV is not so good. This is because you have to speed up the fps rate and images captured will be compress too much and will loss some detail.
Of course it is not so good, but it still can be done, so for those don't have motor drive can still try it out. Also, you don't need to take all the video at one go, you can take a few clip and put them together.
After some experiment done, ToUcam is best to set at 10fps and 5fsp.
If seeing is good, we do not need to capture up to 1800 frames. Due to Jupiter's rotation is fast at 9.8hours per round. So we cannot take too long to prevent errors that may occur while stacking them up.
Even at 5fps, you just need 360 second to get all the 1800 frames which is around 6 minutes of video clip. Even you take 20 minutes to capture all the neccessary frames, I don't think the jupiter's rotation will cause any error on your clip, because the resolution of video clip is too low.
Happy imgaing and have a nice day.
Yang Weixing "The universe is composed mainly of hydrogen and ignorance."