Kx and Star Photography

I've seen a lot of very impressive photos of the night sky (not just on here, and many taken with other brands of camera), and have done some reasonable captures of the ISS flypast as a trail, and I'm thinking of getting a bit more into this as the weather gets a bit better. I have a Kx and either a kit 18-55 or a Sigma 18-200 lens to use, and while I do keep scanning the classifieds for a newer body, I'm also conscious that there's a lot the Kx can do before my skill level overtakes the camera (to clarify, I mean it can do more than I know how to use), so I don't want to just upgrade for the sake of it. Also it's just something I find reasonably interesting - I'm just taking photos from the back garden, not thinking of building an observatory any time soon.

Am I expecting too much to get decent images without terrible amounts of noise, or is the Kx capable of doing this? And can someone point me to any good tutorials on what post-processing I should be doing? I'm not thinking I can pop outside, set the tripod up, and come back ten minutes later with a killer image, but I don't want to waste time if all I'm ever going to achieve is a noisy image where the stars can't be distinguished from the noise.

I asked this on another thread, and was pointed to Deep Sky Stacker which I have downloaded and will experiment with, also the O-GPS unit was suggested but doesn't work with Kx as far as I can tell. I thought I'd start a separate post because (a) I was interrupting a quite separate discussion, and (b) thought I might get more general views. Or is everyone using K5 or K3 nowadays?

OK, thanks for that. I get that I'm not making it easy for myself here in an area where there are streetlamps where you don't want them and none where you do, just wanted to have an idea of what's possible. Good to see images from a similar model, as I think most of the stuff I've seen is perhaps from something much higher spec.

I think if you use the kit lens wide open and at 18mm you should manage some photos. Star trails will be easier than trying to "stop" the stars.
If you cab afford it then something like the Samyang would be good. It is fairly cheap but seems to be popular for this sort of thing.
I bought mine for the US trip to have the best possible chance of reasonable star photos. I didn't get a chance to practice before we went, which would have helped a lot I think.
If we get back to La Palma anytime the Samyang will be in the bag.

It is a pretty good landscape lens (though too wide really for my taste) but hopeless with verticals!

Have fun playing. Patience is the key.

If you want stars as points rather than trails the 500(or 600) rule is a good starting point.

Max exposure in s. before stars begin to show as trails = 500 (or 600)/(focal length of lens x crop factor)

There is some debate as to which is more correct and when stars begin to show up as trails depends on the declination (the sky equivalent of latitude) of the star and it is not really a 'rule' - more guidelines, but a place to start.

With 18mm lens the max exposure on a KX is about 22s (using 600) or 18s (using 500)

I think it is a matter of using the widest aperture and upping the ISO until you get something, and needing a really dark sky; sensors are very good at picking up light pollution.

Dave

The K5 will give you better Astro images, more flexibility (i.e. O-GPS1 compatible), and will allow you to use higher iso more successfully - but you should still be able to get some very good images with the KX. To keep costs down (and figure out if you want to get into it further) then personally I would pick up an older prime lens - an A series 28/2.8 or even an A50/1.7 to take advantage of the faster aperture. A photo taken with the A50/1.7 at f2.0 will gather twice as much light as F2.8, allowing you to capture some basic deep-sky images at iso1600 or 3200. You will need to post-process, and it will be fiddly and often disappointing, but once you start to develop your technique I think you'll be surprised at what you can capture. Deep Sky Stacker is excellent, but is not the easiest of tools to use - it took me several evenings to get a good basic technique, but the advantages of "stacking" multiple shorter exposures will bring out more detail in your final image.

It's not particularly user friendly, and there are not many base level tutorials to help either in my experience.

Watch they don't lose that natural look either, in that often they come out as very dark with very bright stars, which look (I don't know how best to say this) very digital, almost blocky etc. Just an observation.

Thanks for all the comments everyone. I will do some playing around and see what I can do, and if I get something that looks worthwhile I'll post it here and see what people think. I've been looking at the various stars and trying to get familiar with what's up there - I do walk quite a distance to the pub so on a clear night I can get a lot of practice.

I have a film SLR - the noise thing is a good point, but of course it does add the hassle of having to develop (or get someone to develop) the film. I do also keep a look out for older lenses and will have a look at the Samyang lens - I've heard people talk of them before. OGPS looked quite expensive, but I followed a link to someone selling them at £149, still a fair amount of money but not terrible if I decide to go further with this, though I would need to add another body - it just seems wrong to be looking at changing that (especially as a used Kx seems to have very little value) when I've barely touched on what it can do.

Thank you for sharing! I'm just getting into astrophotography and that article looks really interesting and informative!

Thanks for that. I've read a couple of similar ones, to be honest it was really the question of whether I'm expecting too much from the camera that was concerning me.

If you go to http://digital-photography-school.com/ you will find an article on shooting stars with a kit lens.
I can't link to the article right now - I saw it on a news feed, but the actual website seems to be down at the moment. Keep trying it though, the article is interesting to read, and may be helpful

Edit here is the correct link: http://digital-photography-school.com/photographing-stars-using-a-kit-lens/

Thanks for that. I'll be having a play later, there's an ISS pass tonight at around 20:51 so if the sky is clear I'll have a go. I did some the other night that I haven't looked at yet, just for a change I used my manual Mirage 28mm f2.8 lens to see if the extra aperture helped. I have seen a used 50mm f1.7 lens locally, but it's on the front of a film camera and to my mind a bit pricey. If it's gone next time I visit, looks like someone else disagreed.

Having merged some images of the ISS the other night, it seems that getting a decent number of shots to build up the length of the pass is great...




but it really needs some foreground object to bring some perspective.




So I need to combine both of them for next time, and try to match the longer pass with the foreground. But of course the issue is that while I have multiple 5s exposures built together to form the ISS trail, the stars are now turning into trails which isn't helping the image.

Though really these weren't the kind of thing I was talking about.