Planetary Imaging - Getting focus

[Stu Ward]

To all you planetary images out there

I have been trying to image Jupiter the last few nights.
Seeing has been awful so i'm sure that is not helping.
But of the good frames, none seem to be in proper focus, so my question is, How do you do it ?

Any tips would be appreciated.

Using a Philips SPC900NC webcam

Stu

[darbyvet (Carl Darby)]

Hi Stu,
getting good focus in bad seeing is really difficult. Sometimes what I do is take several avis and adjust the focus a little each time in the hope that one will be in focus.The other thing you can do is reduce the gain to mae the image more contrasty to judge focus and then increase it again before you start recording.You can also try to focus using a Jupiter moon.Keep adjusting focus until the moon is as small as possible. The final trick is to use the moon to focus if it is in the sky.It is easier to focus using the moon and then slew to Jupiter.
Once you have seen JUpiter in really good seeing you will find it easier to focus.

[iceman (Mike)]

I echo everything Carl says.

Use one of Jupiter's moons, or use a spot/storm on Jupiter if you can't find an available Moon.

And when the seeing is bad, everything looks out of focus with no detail. Your focus may have been ok, but just hard to tell in bad seeing.

[Stu Ward]

Thanks for the info guys.
I will try all the tips.

Looks like it might just be a case of bad seeing.
Not much I can do about that !

[bmitchell82 (Brendan)]

you could use a FWHM program on a moon of jupiter im guessing as its not much different than a star. it just measures the fuzzy edge to the peak of the star the lower the number the sharper the image, quick easy if your camera is in the hole

[AndyK (Andy)]

Originally Posted by bmitchell82

... you could use a FWHM program ...

Try: http://velatron.com/dca/hocus/ for some freeware which may be of use.
It's an old program but the XP version works fine on my Windows 7 laptop.

[wasyoungonce (Brendan)]

The above gents are 100% correct use Jupiter's moons.

I found this best because of the frame rate and sensitivity of the SPC900NC.