Planets Index

Planets

Techniques.

Your telescope should be in optimum condition for planetary imaging. Check and recheck the collimation of your system before starting, especially with SCT's. Wait until the telescope has the same temperature as the surrounding air. Check the seeing visually, don't image if turbulence is bad - it's a waste of time.

For planetary imaging, you need a long focal length. On film this means using either barlow projection or eyepiece projection. This also means low light levels and long exposure times (2 to 7 seconds) so that good results on film are very difficult to obtain.

This is different with CCD camera's where you can use a shorter focal length and shorter exposures due to the higher sensitivity of the CCD. Aim for 0.5 to 0.25 arcseconds resolution per pixel using one or two barlows or eyepiece projection. With CCD you can make a lot more images in a shorter time than is possible with film. Download time of the CCD images dwhen using a parallel cable/port is slow which limits the number of images (this will improve a lot with cameras using USB to connect to the PC).

Focussing is difficult, take your time and learn to assess when the image on the screen is sharp (raw images on the screen do not always look sharp although you are in focus).

Enter the webcam: a simple device that is capable of outstanding results due to the fact that such cameras have small pixels, have good sensitivity and by "filming" the planet you make hundreds of images in a short time. The rest is patience in checking for the best pictures and combining them with software (avi2bmp, Registax...).

Mars Index.

Mars is much smaller than Jupiter and Saturn (both in real and apparent size). But it is bright and at favorable oppositions can be a fascinating target which I will surely try.

Jupiter Index.

Saturn Index.

With Saturn, you have more time to make images since the planet features rotate much slower than on Jupiter.

Year 1998.

Year 1999.