I'd love to know more about how to go about astro photography. How much would it cost to get into it.
Astrophotography is a money pit but you can start off pretty cheap. You can do pretty decent with a
DIY barn door mount and a wide angle or zoom lens on a DSLR. If your Fuji can take long exposure pictures (I'm not familiar with the camera) you could even use it. It will at least introduce you to guiding concepts and the importance of the mount. If you skip this step I would recommend jumping to a decent German Equatorial Mount as the cheap ones really aren't good for more than whetting your appetite. If you were to spend money in one place first, it would be on a good mount. You will get bad results even with the best telescope without a mount capable of guiding it accurately.
Can you recommend a decent beginner scope, what is a good camera choice, what lens must you use. I have seen a few telescopes for sale locally but can never tell which are decent.
For an entry level scope I would recommend a apochromatic doublet or tripplet refractor. Make sure it has extra low dispersion glass. I would recommend a variant of the ED80 or ED80T. Lots of different companies make them. The doublet designs run 400-600 and the triplet designs from 700-1000+. Triplet designs are a little bit better in terms of chromatic dispersion (they use 3 lenses to correct for this instead of two) but either one is fine. These scopes are pretty good for wide angle astrophotography (similar in framing scale to the pictures I posted) and if you ever decide to move to a nicer instrument the ED80s make great guide telescopes for focal lengths up to 2000 mm.
I also just have a Fuji x100, should would need to sell it for a DSLR.
Yeah you would need either a CCD sensor or a DSLR and a tring to adapt to the telescope. DSLRs are nice because they are dual purpose and can be used for normal photography but the best results will come from monochrome CCDs and colored filter combinations. There are also one shot CCDs that aren't too expensive (500ish) that you can use to start out with if you don't want to get a DSLR. These starter CCDs have pretty small imaging sensors but produce nice results. Large sensor astrophotography CCDs are very very expensive (10k+) so DSLRs are a great option if you want to use a big sensor. You should keep in mind that commercial DSLRs have cut filters which will attenuate H-alpha emissions (deep red nebulous areas). Even with this filtering you can take nice images but the cameras can also be modified to remove the cut filters for better results. There are DIY instructions out there to do it to your camera yourself or you can pay for professionals to do it. Also, Canon makes a camera that is already modified like this (60 Da). I have a modified Canon 6D.
Also, how do "image stacks" work?
Stacking images works to increase the signal to noise ratio in the image. When you take raw astrographs at long sample times the images are typically noisy and the very faint dust trails or nebulous regions can be close to the noise floor. By taking lots of exposures and averaging them, the signal representing real data is always there and stays at the level captured in each image while the noise, which is random, is averaged towards zero. In this way you separate faint details from the background noise. The more shots you stack, the more aggressively you can level stretch the image without it looking like a noisy mess. Increasing exposure time also increases signal to noise ratio so balancing the two methods are key to getting good results. You can either stack in Photoshop or use free software such as deep sky stacker which performs automatic alignment and more advanced averaging algorithms.
Below is a raw image from the Veil Nebula image posted above. There is very bad vignetting (fixed by flat frame subtraction), thermal noise (fixed by bias and dark frame subtraction), and bad signal to noise ratio (fixed by stacking). This is representative to what you get out of the scope on a raw shot. Of course I was just messing around with a new toy on a Monday night with this target. I could have improved my results a lot by increasing my exposure time to pick up some of the fainter nebulosity. Still the results of stacking and image correction greatly improve the end result.
Could you recommend any sites to read up on it to get started. Im just considering it at the moment.
http://www.astropix.com/HTML/I_ASTROP/QUICK.HTM
Has some good information. The author also published a book on DSLR astrophotography which I have heard good things about.
Also, to get these types of images do you have to travel into the hills or mountains away from light pollution? The skies in Ireland arent always great either, so not sure how often I would actually be able to use it. Any info would ge great, thanks.
The shots above were taken in my front yard in northern VA. I live out side the metro area but I am surrounded by pretty bad light pollution from Washington DC and the surrounding metro area. I use a
light pollution filter which seems to help quite a bit and I try to pick targets not sitting right over the city. Point is, you don't need the darkest skies for good results (but it does help a whole lot).
[url=https://flic.kr/p/nLv3t3]
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