Digital Rust

There are so many ways to do this and a multitude of websites that go into further detail, none the less...............here is how I do it.
If any of the terminology here is not familliar you should do searches to find out what it means ( or e-mail me ) for more details

Deep sky objects

Boot your laptop and hook it up to you DSLR using either USB2 or a firewire cable, don't connect it to the telescope yet but make sure everything is working and your "live view" mode is happy

first Polar align your mount - this is crucial if you don't have an autoguiding facility
Put the telescope on your mount and adjust your polar alignment again.........you must make this as accurate as possible

Power up you mount drive electronics / computer and perform whatever goto indexing is required

locate your target object. Don't start with anything very dim........make it easy on yourself and find something you can at least make out in your telescope eyepiece. I will assume there is a brightish star in your field of view nearby the object you want to photograph.

Replace your eyepiece with your DSLR (and adapters) and focus the brightish star you found using your laptop "live view". If like me, you have a newtonian you will see maybe 4 "diffraction spikes" around the star. These must be sharp and you should not see " double" spikes. Carefully focus in and out until they are as sharp as possible.

This next part is experimental but try an iso of 800 and an exposure of 20 seconds to start with. If the photo comes back with nice round points of light try increasing the exposure time to a minute. Eventually your stars will start looking potato shaped and this is the limiting factor of your mounts drive accuracy. As a reference, on a good night I can manage about 1 minute of exposure time.

Keep taking pictures of your target, don't worry about it being dim. If you get a gust of wind or your mount jumps a little......dump that photo and carry on with the next. Collect as many as you can...............for arguments sake 30 good crisp pictures ( out of maybe 50 you have taken )

Yes you will be cold, yes there will be lots of gusts of wind, yes planes/satellites will cross the sky and ruin a good frame and yes you will wonder if it's worth it.

Go back inside and dump all your 30 good pictures ( out of the original 50 ) into your main P.C It is vital that you ensure these are good photo's with no potato shaped stars

Import these pictures into deep sky stacker and tell it to stack your photos.
After a period of time ( depends on the speed of your computer) a rather misty and murky picture will be generated of the object you have spent most of the night trying to photograph.......fear not
Save this image as a 32bit Tiff file and open it back up in photoshop. Use photoshop to convert this into a 16 bit image and save it as a PSD file. You can now adjust the levels and curves to process the image and produce your photograph



voila ;-)

The above is more about the methodology I use than hard instructions. A lot of this stuff is trial and error........be prepared for lots of crap sessions. Is it worth it.........I think so

As a final note, there are many, many valuable sources of info on image processing on the internet. It is a very important component of the final image so learn as much about this stage as possible.