Motorising a Skylux mount.

carlobeirnes wrote: There is nothing better than a CCD camera to tell you how good your mount is. Ask any astrophotographor what is there biggest investment when it comes to astrophotography they will aways say the mount everytime.
Carl.

Too true.

But in the case of a DSLR with a really short focal length, you would surely get some reasonable of images of bright objects? Of course, there is always the option to keep the camera still and get some star rotation shots.

I'd totally agree with long focal lengths - I operate at 3890mm - I can just about manage a 5 min exposure with the AP1200 without getting eggy stars (no guiding of course).

I think Keith G is using a DSLR for those lovely wide-field shots. Not sure what he mounts it on. Keith?

Cheers
Dave

I've just been re-reading down through the thread here, and I don't think I made it clear how wide angle I'm going.
I'm talking about focal lengths from 18mm to a max of 50mm, mainly sticking to the lower end. At that length, you can get away with close to 30secs without any tracking at all. At that rate, I could do longer exposures then just manually tracking on an GEM, couldn't I?(although this would be a pain in the ass!) A focal length of 18mm should be extremely forgiving, so even if the tracking wasn't 100%, I should get away with it.

I'm not trying to be argumentitive, I'm just trying to get my head around this.

(Binocular observing was so much simpler!)

Actually, Frank Ryan Jr has a great example of the kind of stuff I'm after, on his Flickr Page



Frank, I hope you don't mind me posting this here, oh, and I love this shot!


There's another example here .
This one isn't Frank's.

You're right - any mototrised mounting that you use to track the movement of stars/planets/moon should be far more forgiving at shorter focal lengths than the waaaay longer focal lengths.

Manual tracking is of course the cheapest option - with a finder scope attached to the DSLR or mounted adjacent to it, I'd imagine you could get fairly long exposures before you got bored/tired/cold.

Motorised tracking - for starters, I'd go with the cheapest option I possibly could to get my teeth into it. The tracking still has to be reasonable though or you'll be disappointed with mediocre images at best. The better the tracking, the better the images, but the greater the price.

If I were you, I'd go for the Bresser motor set whilst saving up, or at least considering upgrading to, the Astrotrac in the near future - if you like what you're doing. If you feel the wide-angle stuff is not for you or the Bresser gives you as good as you need, then you can consider longer focal length imaging with all the attendant costs and pain. And the money you have saved up will get you on the road to half decent equipment and a reasonable supply of Panadol Extra.

Dave

Leo,

I'd be inclined to agree with what the lads said. Even at lower focal lengths, I worry if the bresser kit will give you what your looking for. At first you'll think great its working, but then after the initial excitement dies down you'll start to look a bit more critically at your images and realise that you could make em that bit better if you could track better. At first you'll put it down to polar alignment then eventually realise that the mount is just not all you think it is. But guess what you just shelled out your budget on the bresser kit.

My advice, keep saving until you can get hold of a second hand astrotrac or maybe a cg5. If you go for the latter then you have the option of adding a scope later once you've mastered the wide field stuff. ..............and please don't tell me you wont want to mount a scope, you know you will eventually.

I'm not trying to rain on your parade. I've been there too blown money on kit that i thought would fit the bill, finally realising that if your serious about astrophotography patience and saving are your best friends.

Leo,

Just looking at Franks gorgeous shot above got me thinking. Frank uses an astrotrac. (AT least he did at some point). Talk to Frank and ask him why he bought the astrotrac. I think he used some sort of lower end kit at first but later upgraded. Might be worth asking why. Know what I mean?