 |
| In action - composite photo of the ISS pass |
When I first bought a scope for myself and became aware that there is this thing called ISS, I immediately thought to try to take an image of it. Than I've seen some of the best ISS photos on the web and I was immediately hooked. I wanted to do the same :)
The only way this could be done for beginners is manually moving the scope and hoping to capture a few useful frames.
Before you do anything outdoors, check what's happening, find details to know what you're dealing with (brightness, elevation, duration, etc.).
I normally get a pretty good summary of information from www.heavens-above.com. Here is a screenshot from the website about the ISS pass I've recorded.
 |
| Screesnshot from www.heavens-above.com |
First and probably most important step is to align my reddot finder/Telrad/finder (whichever you have) scope dead accurate with my main scope. It means wherever I'm pointing my Telrad, my main scope will have the same object centered in the eyepiece/camera/dslr. This is very very important, because due relatively high magnification a small error will result in not having ISS in your camera's field of view at all. Therefore all goes to bin....
I made this mistake a few times and was frustrated a lot :) But hey, mistakes are to learn from them right!
Once finder is aligned to scope, the second important thing is camera settings.
I can't give you any exact advises on that, every planetary camera/dslr has it's own sensitivity, therefore you have to find it out for yourself. Yes it means experimenting with your equipment. What I can give you is my experience at a given equipment.
Two ways of doing imaging. let's assume we are setting up for a very bright (between mag -2.5 and mag -3.5)
- Using a dslr camera. Depending on the dslr you're using, you can record video or take raw/jpeg photos on continuous mode. Usually for photos the settings I've used at very bright passes was shutter at 1/1250 and ISO at either 800 or 1600 (equipment 90/1250 maksutov + Canon 600D)- Using a planetary camera. I personally use a Zwo ASI 120MC, settings usually and the settings on this particular attempt at mag -3.0 was: Shutter 0.800 and Gain 60 ( equipment 127/1500 maksutov + Zwo ASI 120MC color camera).
(Update: My color camera is gone, instead I'll use a 120MM mono version from now on. The first shots are at the bottom of the post, taken through hazy sky.)
The rest of the job is determination, enthusiasm and a never giving up attitude :)
I used to use an equatorial mount for manually tracking ISS, but my experience is not the best with it. An Alt-Az mount or a dobsonian type scope is probably the best for this purpose.
Here is a video about how imaging works for me. Time lapse of 10s expos about the preparations and the pass itself.
Sometimes I've got comments like "nice CGI" or "green screen, fake" etc. Well I can not document the event better than this, if someone chooses not to accept that Earth is a globe (not flat) and things actually orbiting around it, I can't really argue any longer....
Have one of these apps:
- ISS Detector (android)
- Sputnik (iOS)
These two images below were taken with a Skywatcher 250/1200 Flextube scope on a dobson platform, that seems to have advantages by its built to follow ISS much easier, than doing the same with an equatorial of alt-az platform. Also a Zwo ASI 120MM mono camera was used to capture frames.
 |
| Taken with my new ASI 120MM monochrome camera |
 |
| Japanese HTV-6 docked and a month later gone |
The blog post will hopefully give you a good idea, how this is exactly done. It works for me and hope you might find it useful.
Good luck!!
Best way to get good information about the overhead passes
Heavens Above: www.heavens-above.com
Transits: http://www.calsky.com/cs.cgi
No comments:
Post a Comment