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Okay gents,
The camera is an EOS 1100d; I have an adapter that I can attach a nosepiece to & fit the camera to my 8"SCT sans lenses - ie: Prime focus.
I can & have taken photos of planets & the moon; I have no trouble at all seeing them through live view on both the back of the camera, on my computer or in the app (on an android tablet) that I am using. If I attempt to take still images of planets I find that they are rarely in tight focus due to the seeing conditions up here in Cairns... the visual seeing can be quite reasonable but, even then you can see the planets shimmering, this translates to just not quite in focus in the camera.
After trying to get a starfield & nebula in frame last night, (Swan Nebula) which, I could clearly see in an eye piece both with & without a UHC filter, I found that I simply could not see anything in live view, nothing, not even a hint of light. Took the shot anyway, which did result in some fuzzy light but, nothing in focus.
Slewed to a bright star, tried again - again, nothing in liveview. Took the shot anyway (30 sec exposure at ISO 800) and got the donut shape of an out of focus star but, still cannot see anything in the live view image. Fiddled with focus & kept taking shots, got a smaller donut but, decided this was a very hit & miss way to attempt to focus & gave up on that method.
Slewed to Saturn, achieved reasonable focus but, again could see the planet shimmering in the live view image, still had plenty of focus range left in either direction (I know this because I could get the image to move in & out of focus in both directions), slewed back to nebula, still could see nothing in live view, took a shot anyway at 30 sec, ISO 800. Got some stars but, no nebula so, figured that my FOV was probably slight off the nebula. Looked in my finder scope (60mm that takes 1.25 eyepieces & has a helical focuser), couldn't find the nebula, clouds rolled in & I gave up in frustration.
Slightly different subject but, related. Attempted some video of mars too, image waaaay to bright. Need to look up more about adjusting 'something' too avoid the overly bright video images too. But, I'll read up on that later.
Moon & planet shots taken recently posted below, the saturn shot is a single exposure, the Jupiter shot is multiple exposures stacked in Registax but, the seeing conditions were not perfect & the focus is a bit off on the planet shots (first attempt at prime focus). As you will see, the moon shots are fairly tight for focus.
I understand that perhaps I am not in focus when trying to see the stars through live view but, if I use a planet to do initial focus (which I can without drama), how can I be sure that I have the desired object (nebula in this case) in my FOV when I slew back?
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