Problem focusing with webcam

[Rapallokid]

Hi, this is a beginners question but thought it might get the correct response in this section.

I am using a nexstar 6 and a phillips moded webcam to do some very basic imaging but am having trouble getting any planets into focus.

I have managed to get the moon in focus ( easy big target) but when i try jupiter or in the case of this morning saturn, I cant get an image up. I am using sharpcap but to no avail.

I have tried rotating the focuser slowly through the complete spectrum but nothing.

The process I use is by locating object with 25mm ep. centering it then switching from ep to cam. I have also tried using barlow 2 x but think that would just make it more difficult.

Any advise would be appreciated.

[Pete Presland]

locate the planet in a higher power eyepiece before switching to your webcam, also up the brightness setings for webcam to allow for poor focus.

[Clayton]

locate the planet in a higher power eyepiece before switching to your webcam, also up the brightness setings for webcam to allow for poor focus.

Ditto:)

[tbird]

My amatuerish way of focussing on Jupiter is to turn exposure and gain way up, this shows the moons, I then adjust focus to get the moons as bright dots, then adjust exposure and gain as required.

[King]

Yeah, a common problem is neglecting the gain/exposure. The planet could be right there and you won't see it if those settings are too low. Aside from that make sure any finderscope is well aligned. I don't even need a high power eyepiece for the job these days, though that becomes more of an issue the larger the magnification you're going for.

[astrosphinx]

I've had similar problems although I usually get issues when I pop a barlow in.

I tend to agree that overexposure definetely helps but the margin of error is quite tight, even though you may think it's centre with your 25mm, a slight drift (if not goto) between ep / webcam swap is enough for it to be out of frame. I find placing the webcam (nose) in gradually helps locate the out of focus planet. In fact, that's another tip, it's easier to find out of focus because an out of focus planet fills a greater screen area, therefore you can see which way your need to pan prior to focus.

Mind you that's where I need to improve, I can never seem to get the planet pin-sharp.

[Rapallokid]

Many thanks for al of the advice, I will try and see how i get on.

One thing I am confused about is using a higher power ep to locate the target. What difference does this make if you have to remove it to put the webcam in? To me 25mm or 9mm shouldnt make a difference? or is it the point that it is to get a more accurate center in the FOV?

RK

[Clayton]

Yes the point of the higher power is to center more accurately. I tend to use a power that gives me a similar view to the onscreen one.

A good finder is also very helpful as King says, but mine moves too easily out of alignment due to poor mounting