Photographing the International Space Station sounds more daunting than it actually is due to the fact that it has to be manually tracked. Most people dont realize though that it can be one of the easiest and most rewarding targets in astrophotography. The ISS is so easily visable with the naked eye that a correctly aligned telrad finder and a dslr set to video mode can easily capture a great image. this short guide will give a rundown of how to take an image like the one to the right.
The first step to capturing an image of the International Space station is to figure out when the station is going to be overhead, you can figure this out by using an app on you're smartphone or computer, I use ISS detector for android to find out the date, time, magnitude, and angle of the ISS (look for times after dark, magnitudes more negative, and sky angles above 50). I also use a program called stellarium (which is free on the PC and Mac) to figure out the sky path of the ISS. After collimating your dobsonian and finding a nice clear area that allows you to see as much of the sky as possible from where you are located, attach your camera to the telescope via the t-ring and t-adapter, also attach the barlow inbetween the telescope and camera as you wouldnt be able to achieve focus on a dobsonian without one.
(Order of attachments left to right: Barlow, T-adapter, T-ring, DSLR)
Now that the camera is attached to your telescope, switch to video mode and find the brightest star you can (vega or sirius work great) and adjust the focus till the star is as focused as it can get (the smaller the star on your screen, the more focused that star is). When you are done focusing on a star, place the star in the center of your field of view then adjust your telrad finder so that the star is also centered in the telrad. next change your ISO to somewhere between 1600 and 3200 depending on the magnitude of the ISS and your camera. Now switch the shutter speed to something fast, around 1/600 or more, this will prevent blurring as the ISS is moving extremely fast in the sky and in and out of your field of view as you are manualy tracking it. you are now ready to capture the ISS.
The key to getting a great image as you manually track the ISS is to only watch it through your telrad, making sure to keep it as centered as possible, this is where the shutter remote comes in handy as you can control the camera without having to take your eye off of the telrad. Track it and take video as it moves from one horizon to the other, i like to take a couple videos as opposed to 1 long video to make processing easier, but that is up to you. thats really all there is to the aquisition side of the ISS so at this point you should have data that looks somewhat like this:
Now that you have the raw footage of the ISS, its time to process it using PiPP aka Planetary imaging PreProcessor (free software, link below). Open and drag the raw footage you captured from your cameras SD card to the source file tab in PiPP and on the bottom right corner there should be an Optimisation box, select ISS. If you have multiple files from the same session, select the Join option at the bottom of the source file tab. Under the Processing options tab, check that object/Planetary is selected under frame stabilisation mode, and to enable object detection, also at the bottom right you have the option to crop, I usually select this as i dont care to have a large amount of empty space around the ISS. Next switch to the output tab and make sure tiff also select an output folder you want all the images to be stored in, you can also enable quality estimation if you want under the quality options tab. last switch to the Do processing tab and press start processing, when processing is done all you have to do is browse all the images sent to your selected output directory and choose which image you like best and you're done!